Blog
/
Cloud
/
June 12, 2024

Meeten Malware: A Cross-Platform Threat to Crypto Wallets on macOS and Windows

Cado Security Labs (now part of Darktrace) identified a "Meeten" campaign deploying a cross-platform (macOS/Windows) infostealer called Realst. Threat actors create fake Web3 companies with AI-generated content and social media to trick targets into downloading malicious meeting applications.
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Tara Gould
Threat Researcher
Default blog imageDefault blog imageDefault blog imageDefault blog imageDefault blog imageDefault blog image
12
Jun 2024

Introduction: Meeten malware

Researchers from Cado Security Labs (now part of Darktrace) have identified a new sophisticated scam targeting people who work in Web3. The campaign includes cryptostealer Realst that has both macOS and Windows variants, and has been active for around four months. Research shows that the threat actors behind the malware have set up fake companies using AI to make them increase legitimacy. The company, which is currently going by the name “Meetio”, has cycled through various names over the past few months. In order to appear as a legitimate company, the threat actors created a website with AI-generated content, along with social media accounts. The company reaches out to targets to set up a video call, prompting the user to download the meeting application from the website, which is Realst info stealer. 

Meeten

Screenshot of fake company homepage
Figure 1: Fake company homepage

“Meeten” is the application that is attempting to scam users into downloading an information stealer. The company regularly changes names, and has also gone by Clusee[.]com, Cuesee, Meeten[.]gg, Meeten[.]us, Meetone[.]gg and is currently going by the name Meetio. In order to gain credibility, the threat actors set up full company websites, with AI-generated blog and product content and social media accounts including Twitter and Medium.

Based on public reports from targets (withheld from this post for privacy), the scam is conducted in multiple ways. In one reported instance, a user was contacted on Telegram by someone they knew who wanted to discuss a business opportunity and to schedule a call. However, the Telegram account was created to impersonate a contact of the target. Even more interestingly, the scammer sent an investment presentation from the target’s company to him, indicating a sophisticated and targeted scam. Other reports of targeted users report being on calls related to Web3 work, downloading the software and having their cryptocurrency stolen.

After initial contact, the target would be directed to the Meeten website to download the product. In addition to hosting information stealers, the Meeten websites contain Javascript to steal cryptocurrency that is stored in web browsers, even before installing any malware. 

Script
Figure 2: Script

Technical analysis

macOS version

Name: CallCSSetup.pkg

Meeten downloads page
Figure 3: Downloads page on Meeten

Once the victim is directed to the “Meeten” website, the downloads page offers macOS or Windows/Linux. In this iteration of the website, all download links lead to the macOS version. The package file contains a 64-bit binary named “fastquery”, however other versions of the malware are distributed as a DMG with a multi-arch binary. The binary is written in Rust, with the main functionality being information stealing. 

When opened, two error messages appear. The first one states “Cannot connect to the server. Please reinstall or use a VPN.” with a continue button. Osascript, the macOS command-line tool for running AppleScript and JavaScript is used to prompt the user for their password, as commonly seen in macOS malware. [1]

Pop up
Figure 4: Popup that requests users password
Code
Figure 5

The malware iterates through various data stores, grabs sensitive information, creates a folder where the data is stored, and then exfiltrates the data as a zip. 

Folders
Figure 6: Folders and files created by Meeten

Realst Stealer looks for and exfiltrates if available:

  • Telegram credentials
  • Banking card details
  • Keychain credentials
  • Browser cookies and autofill credentials from Google Chrome, Opera, Brave, Microsoft Edge, Arc, CocCoc and Vivaldi
  • Ledger Wallets
  • Trezor Wallets

The data is sent to 139[.]162[.]179.170:8080/new_analytics with “log_id”, “anal_data” and “archive”. This contains the zip data to be exfiltrated along with analytics that include build name, build version, with system information. 

System information
Figure 7: System information that is sent as a log

Build information is also sent to 139[.]162[.]179.170:8080/opened along with metrics sent to /metrics. Following the data exfiltration, the created temporary directories are removed from the system. 

Windows version

Name: MeetenApp.exe

Meeten Setup Install
Figure 8: Meeten Setup install

While analyzing the macOS version of Meeten, Cado Security Labs identified a Windows version of the malware. The binary, “MeetenApp.exe” is a Nullsoft Scriptable Installer System (NSIS) file, with a legitimate signature from “Brys Software” that has likely been stolen.

Digital signature details
Figure 9: Digital Signature of Meeten

After extracting the files from the installer, there are two folders $PLUGINDIR and $R0. Inside $PLUGINDIR is a 7zip archive named “app-64” that contains resources, assets, binaries and an app.asar file, indicating this is an Electron application. Electron applications are built on the Electron framework that is used to develop cross-platform desktop applications with web languages such as Javascript. App.asar files are used by Electron runtime, and is a virtual file system containing application code, assets, and dependencies.

File structure
Figure 10: Electron application meeten structure
Meeten's app .asar file
Figure 11: Structure of Meeten's App.asar file
package.json
Figure 12: Package.json

After extracting the contents of app.asar, we can see the main script points to index.js containing:

"use strict"; 
require("./bytecode-loader.cjs"); 
require("./index.jsc"); 

Both of these are Bytenode Compiled Javascript files. Bytenode is a tool that compiles JavaScript code into V8 bytecode, allowing the execution of JavaScript without exposing the source code. The bytecode is a low-level representation of the JavaScript code that can be executed by the V8 JavaScript engine which powers Node.js. Since the Javascript is compiled, reverse engineering of the files is more difficult, and less likely to be detected by security tools. 

While the file is compiled, there is still some information we can see as plain text. Similarly to the macOS version, a log with system information is sent to a remote server. A secondary password protected archive , “AdditionalFilesForMeet.zip” is retrieved from deliverynetwork[.]observer into a temporary directory “temp03241242”.

URL
Figure 13

From AdditionalFilesForMeet.zip is a binary named “MicrosoftRuntimeComponentsX86.exe” This binary gathers system information including HWID, geo IP, hostname, OS, users, cores, RAM, disk size and running processes. 

Exfiltrated system information
Figure 14: System information exfiltrated by Meeten

This data is sent to 172[.]104.133.212/opened, along with the build version of Meeten. 

Data
Figure 15

An additional payload is retrieved “UpdateMC.zip” from “deliverynetwork[.]observer/qfast” into AppData/Local/Temp. The archive file extracts to UpdateMC.exe. 

UpdateMC

UpdateMC.exe is a Rust-based binary, with similar functionality to the macOS version. The stealer searches in various data stores to collect and exfiltrate sensitive data as a zip. Meeten has the ability to steal data from:

  • Telegram credentials
  • Banking card details
  • Browser cookies, history and autofill credentials from Google Chrome, Opera, Brave, Microsoft Edge, Arc, CocCoc and Vivaldi
  • Ledger Wallets
  • Trezor Wallets
  • Phantom Wallets
  • Binance Wallets

The data is stored inside a folder named after the users’ HWID inside AppData/Local/Temp directory before being exfiltrated to 172[.]104.133.212. 

Domains.txt
Figure 16

For persistence, a registry key is added to HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Run to ensure that the stealer is run each time the machine is started. 

Code
Figure 17: Disassembled code where 0xFFFFFFFF80000001 = HKEY_CURRENT_USER
Code
Figure 18: Meeten uses RegSetValueExW call to set registry key
Computer folder
Figure 19

Key takeaways 

This blog highlights a sophisticated campaign that uses AI to social engineer victims into downloading low detected malware that has the ability to steal financial information. Although the use of malicious Electron applications is relatively new, there has been an increase of threat actors creating malware with Electron applications. [2] As Electron apps become increasingly common, users must remain vigilant by verifying sources, implementing strict security practices, and monitoring for suspicious activity.

While much of the recent focus has been on the potential of AI to create malware, threat actors are increasingly using AI to generate content for their campaigns. Using AI enables threat actors to quickly create realistic website content that adds legitimacy to their scams, and makes it more difficult to detect suspicious websites. This shift shows how AI can be used as a powerful tool in social engineering. As a result, users need to exercise caution when being approached about business opportunities, especially through Telegram. Even if the contact appears to be an existing contact, it is important to verify the account and always be diligent when opening links. 

Indicators of compromise (IoCs)

http://172[.]104.133.212:8880/new_analytics

http://172[.]104.133.212:8880/opened

http://172[.]104.133.212:8880/metrics

http://172[.]104.133.212:8880/sede

139[.]162[.]179.170:8080

deliverynetwork[.]observer/qfast/UpdateMC.zip

deliverynetwork[.]observer/qfast/AdditionalFilesForMeet.zip

www[.]meeten.us

www[.]meetio.one

www[.]meetone.gg

www[.]clusee.com

199[.]247.4.86

File / md5

CallCSSetup.pkg  9b2d4837572fb53663fffece9415ec5a  

Meeten.exe  6a925b71afa41d72e4a7d01034e8501b  

UpdateMC.exe  209af36bb119a5e070bad479d73498f7  

MicrosoftRuntimeComponentsX64.exe d74a885545ec5c0143a172047094ed59  

CluseeApp.pkg 09b7650d8b4a6d8c8fbb855d6626e25d

MITRE ATT&CK

Technique name / ID

T1204  User Execution  

T1555.001  Credentials From Password Stores: Keychain  

T1555.003 Credentials From Password Stores: Credentials from Web Browsers  

T1539  Steal Web Session Cookie  

T1217 Browser Information Discovery  

T1082  System Information Discovery  

T1016 System Network Configuration Discovery  

T1033  System Owner/User Discovery  

T1005 Data from Local System

T1074  Local Data Staging  

T1071.001 Application Layer Protocol: Web Protocols  

T1041 Exfiltration Over C2 Channel  

T1657 Financial Theft  

T1070.004 File Deletion  

T1553.001 Subvert Trust Controls: Gatekeeper Bypass  

T1553.002  Subvert Trust Controls: Code Signing  

T1547.001 Boot or Logon Autostart Execution: Registry Run Folder  

T1497.001  Virtualization/Sandbox Evasion: System Checks  

T1058.001 Command and Scripting Interpreter: Powershell  

T1016 Network Configuration Discovery  

T1007 System Service Discovery

References

  1. https://www.darktrace.com/blog/from-the-depths-analyzing-the-cthulhu-stealer-malware-for-macos
  2. https://research.checkpoint.com/2022/new-malware-capable-of-controlling-social-media-accounts-infects-5000-machines-and-is-actively-being-distributed-via-gaming-applications-on-microsofts-official-store/  
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Tara Gould
Threat Researcher

More in this series

No items found.

Blog

/

OT

/

November 20, 2025

Managing OT Remote Access with Zero Trust Control & AI Driven Detection

managing OT remote access with zero trust control and ai driven detectionDefault blog imageDefault blog image

The shift toward IT-OT convergence

Recently, industrial environments have become more connected and dependent on external collaboration. As a result, truly air-gapped OT systems have become less of a reality, especially when working with OEM-managed assets, legacy equipment requiring remote diagnostics, or third-party integrators who routinely connect in.

This convergence, whether it’s driven by digital transformation mandates or operational efficiency goals, are making OT environments more connected, more automated, and more intertwined with IT systems. While this convergence opens new possibilities, it also exposes the environment to risks that traditional OT architectures were never designed to withstand.

The modernization gap and why visibility alone isn’t enough

The push toward modernization has introduced new technology into industrial environments, creating convergence between IT and OT environments, and resulting in a lack of visibility. However, regaining that visibility is just a starting point. Visibility only tells you what is connected, not how access should be governed. And this is where the divide between IT and OT becomes unavoidable.

Security strategies that work well in IT often fall short in OT, where even small missteps can lead to environmental risk, safety incidents, or costly disruptions. Add in mounting regulatory pressure to enforce secure access, enforce segmentation, and demonstrate accountability, and it becomes clear: visibility alone is no longer sufficient. What industrial environments need now is precision. They need control. And they need to implement both without interrupting operations. All this requires identity-based access controls, real-time session oversight, and continuous behavioral detection.

The risk of unmonitored remote access

This risk becomes most evident during critical moments, such as when an OEM needs urgent access to troubleshoot a malfunctioning asset.

Under that time pressure, access is often provisioned quickly with minimal verification, bypassing established processes. Once inside, there’s little to no real-time oversight of user actions whether they’re executing commands, changing configurations, or moving laterally across the network. These actions typically go unlogged or unnoticed until something breaks. At that point, teams are stuck piecing together fragmented logs or post-incident forensics, with no clear line of accountability.  

In environments where uptime is critical and safety is non-negotiable, this level of uncertainty simply isn’t sustainable.

The visibility gap: Who’s doing what, and when?

The fundamental issue we encounter is the disconnect between who has access and what they are doing with it.  

Traditional access management tools may validate credentials and restrict entry points, but they rarely provide real-time visibility into in-session activity. Even fewer can distinguish between expected vendor behavior and subtle signs of compromise, misuse or misconfiguration.  

As a result, OT and security teams are often left blind to the most critical part of the puzzle, intent and behavior.

Closing the gaps with zero trust controls and AI‑driven detection

Managing remote access in OT is no longer just about granting a connection, it’s about enforcing strict access parameters while continuously monitoring for abnormal behavior. This requires a two-pronged approach: precision access control, and intelligent, real-time detection.

Zero Trust access controls provide the foundation. By enforcing identity-based, just-in-time permissions, OT environments can ensure that vendors and remote users only access the systems they’re explicitly authorized to interact with, and only for the time they need. These controls should be granular enough to limit access down to specific devices, commands, or functions. By applying these principles consistently across the Purdue Model, organizations can eliminate reliance on catch-all VPN tunnels, jump servers, and brittle firewall exceptions that expose the environment to excess risk.

Access control is only one part of the equation

Darktrace / OT complements zero trust controls with continuous, AI-driven behavioral detection. Rather than relying on static rules or pre-defined signatures, Darktrace uses Self-Learning AI to build a live, evolving understanding of what’s “normal” in the environment, across every device, protocol, and user. This enables real-time detection of subtle misconfigurations, credential misuse, or lateral movement as they happen, not after the fact.

By correlating user identity and session activity with behavioral analytics, Darktrace gives organizations the full picture: who accessed which system, what actions they performed, how those actions compared to historical norms, and whether any deviations occurred. It eliminates guesswork around remote access sessions and replaces it with clear, contextual insight.

Importantly, Darktrace distinguishes between operational noise and true cyber-relevant anomalies. Unlike other tools that lump everything, from CVE alerts to routine activity, into a single stream, Darktrace separates legitimate remote access behavior from potential misuse or abuse. This means organizations can both audit access from a compliance standpoint and be confident that if a session is ever exploited, the misuse will be surfaced as a high-fidelity, cyber-relevant alert. This approach serves as a compensating control, ensuring that even if access is overextended or misused, the behavior is still visible and actionable.

If a session deviates from learned baselines, such as an unusual command sequence, new lateral movement path, or activity outside of scheduled hours, Darktrace can flag it immediately. These insights can be used to trigger manual investigation or automated enforcement actions, such as access revocation or session isolation, depending on policy.

This layered approach enables real-time decision-making, supports uninterrupted operations, and delivers complete accountability for all remote activity, without slowing down critical work or disrupting industrial workflows.

Where Zero Trust Access Meets AI‑Driven Oversight:

  • Granular Access Enforcement: Role-based, just-in-time access that aligns with Zero Trust principles and meets compliance expectations.
  • Context-Enriched Threat Detection: Self-Learning AI detects anomalous OT behavior in real time and ties threats to access events and user activity.
  • Automated Session Oversight: Behavioral anomalies can trigger alerting or automated controls, reducing time-to-contain while preserving uptime.
  • Full Visibility Across Purdue Layers: Correlated data connects remote access events with device-level behavior, spanning IT and OT layers.
  • Scalable, Passive Monitoring: Passive behavioral learning enables coverage across legacy systems and air-gapped environments, no signatures, agents, or intrusive scans required.

Complete security without compromise

We no longer have to choose between operational agility and security control, or between visibility and simplicity. A Zero Trust approach, reinforced by real-time AI detection, enables secure remote access that is both permission-aware and behavior-aware, tailored to the realities of industrial operations and scalable across diverse environments.

Because when it comes to protecting critical infrastructure, access without detection is a risk and detection without access control is incomplete.

Continue reading
About the author
Pallavi Singh
Product Marketing Manager, OT Security & Compliance

Blog

/

Network

/

November 21, 2025

Xillen Stealer Updates to Version 5 to Evade AI Detection

xillen stealer updates to version 5 to evade ai detectionDefault blog imageDefault blog image

Introduction

Python-based information stealer “Xillen Stealer” has recently released versions 4 and 5, expanding its targeting and functionality. The cross-platform infostealer, originally reported by Cyfirma in September 2025, targets sensitive data including credentials, cryptocurrency wallets, system information, browser data and employs anti-analysis techniques.  

The update to v4/v5 includes significantly more functionality, including:

  • Persistence
  • Ability to steal credentials from password managers, social media accounts, browser data (history, cookies and passwords) from over 100 browsers, cryptocurrency from over 70 wallets
  • Kubernetes configs and secrets
  • Docker scanning
  • Encryption
  • Polymorphism
  • System hooks
  • Peer-to-Peer (P2P) Command-and-Control (C2)
  • Single Sign-On (SSO) collector
  • Time-Based One-Time Passwords (TOTP) and biometric collection
  • EDR bypass
  • AI evasion
  • Interceptor for Two-Factor Authentication (2FA)
  • IoT scanning
  • Data exfiltration via Cloud APIs

Xillen Stealer is marketed on Telegram, with different licenses available for purchase. Users who deploy the malware have access to a professional-looking GUI that enables them to view exfiltrated data, logs, infections, configurations and subscription information.

Screenshot of the Xillen Stealer portal.
Figure 1: Screenshot of the Xillen Stealer portal.

Technical analysis

The following technical analysis examines some of the interesting functions of Xillen Stealer v4 and v5. The main functionality of Xillen Stealer is to steal cryptocurrency, credentials, system information, and account information from a range of stores.

Xillen Stealer specifically targets the following wallets and browsers:

AITargetDectection

Screenshot of Xillen Stealer’s AI Target detection function.
Figure 2: Screenshot of Xillen Stealer’s AI Target detection function.

The ‘AITargetDetection’ class is intended to use AI to detect high-value targets based on weighted indicators and relevant keywords defined in a dictionary. These indicators include “high value targets”, like cryptocurrency wallets, banking data, premium accounts, developer accounts, and business emails. Location indicators include high-value countries such as the United States, United Kingdom, Germany and Japan, along with cryptocurrency-friendly countries and financial hubs. Wealth indicators such as keywords like CEO, trader, investor and VIP have also been defined in a dictionary but are not in use at this time, pointing towards the group’s intent to develop further in the future.

While the class is named ‘AITargetDetection’ and includes placeholder functions for initializing and training a machine learning model, there is no actual implementation of machine learning. Instead, the system relies entirely on rule-based pattern matching for detection and scoring. Even though AI is not actually implemented in this code, it shows how malware developers could use AI in future malicious campaigns.

Screenshot of dead code function.
Figure 3: Screenshot of dead code function.

AI Evasion

Screenshot of AI evasion function to create entropy variance.
Figure 4: Screenshot of AI evasion function to create entropy variance.

‘AIEvasionEngine’ is a module designed to help malware evade AI-based or behavior-based detection systems, such as EDRs and sandboxes. It mimics legitimate user and system behavior, injects statistical noise, randomizes execution patterns, and camouflages resource usage. Its goal is to make the malware appear benign to machine learning detectors. The techniques used to achieve this are:

  • Behavioral Mimicking: Simulates user actions (mouse movement, fake browser use, file/network activity)
  • Noise Injection: Performs random memory, CPU, file, and network operations to confuse behavioral classifiers
  • Timing Randomization: Introduces irregular delays and sleep patterns to avoid timing-based anomaly detection
  • Resource Camouflage: Adjusts CPU and memory usage to imitate normal apps (such as browsers, text editors)
  • API Call Obfuscation: Random system API calls and pattern changes to hide malicious intent
  • Memory Access Obfuscation: Alters access patterns and entropy to bypass ML models monitoring memory behavior

PolymorphicEngine

As part of the “Rust Engine” available in Xillen Stealer is the Polymorphic Engine. The ‘PolymorphicEngine’ struct implements a basic polymorphic transformation system designed for obfuscation and detection evasion. It uses predefined instruction substitutions, control-flow pattern replacements, and dead code injection to produce varied output. The mutate_code() method scans input bytes and replaces recognized instruction patterns with randomized alternatives, then applies control flow obfuscation and inserts non-functional code to increase variability. Additional features include string encryption via XOR and a stub-based packer.

Collectors

DevToolsCollector

Figure 5: Screenshot of Kubernetes data function.

The ‘DevToolsCollector’ is designed to collect sensitive data related to a wide range of developer tools and environments. This includes:

IDE configurations

  • VS Code, VS Code Insiders, Visual Studio
  • JetBrains: Intellij, PyCharm, WebStorm
  • Sublime
  • Atom
  • Notepad++
  • Eclipse

Cloud credentials and configurations

  • AWS
  • GCP
  • Azure
  • Digital Ocean
  • Heroku

SSH keys

Docker & Kubernetes configurations

Git credentials

Database connection information

  • HeidiSQL
  • Navicat
  • DBeaver
  • MySQL Workbench
  • pgAdmin

API keys from .env files

FTP configs

  • FileZilla
  • WinSCP
  • Core FTP

VPN configurations

  • OpenVPN
  • WireGuard
  • NordVPN
  • ExpressVPN
  • CyberGhost

Container persistence

Screenshot of Kubernetes inject function.
Figure 6: Screenshot of Kubernetes inject function.

Biometric Collector

Screenshot of the ‘BiometricCollector’ function.
Figure 7: Screenshot of the ‘BiometricCollector’ function.

The ‘BiometricCollector’ attempts to collect biometric information from Windows systems by scanning the C:\Windows\System32\WinBioDatabase directory, which stores Windows Hello and other biometric configuration data. If accessible, it reads the contents of each file, encodes them in Base64, preparing them for later exfiltration. While the data here is typically encrypted by Windows, its collection indicates an attempt to extract sensitive biometric data.

Password Managers

The ‘PasswordManagerCollector’ function attempts to steal credentials stored in password managers including, OnePass, LastPass, BitWarden, Dashlane, NordPass and KeePass. However, this function is limited to Windows systems only.

SSOCollector

The ‘SSOCollector’ class is designed to collect authentication tokens related to SSO systems. It targets three main sources: Azure Active Directory tokens stored under TokenBroker\Cache, Kerberos tickets obtained through the klist command, and Google Cloud authentication data in user configuration folders. For each source, it checks known directories or commands, reads partial file contents, and stores the results as in a dictionary. Once again, this function is limited to Windows systems.

TOTP Collector

The ‘TOTP Collector’ class attempts to collect TOTPs from:

  • Authy Desktop by locating and reading from Authy.db SQLite databases
  • Microsoft Authenticator by scanning known application data paths for stored binary files
  • TOTP-related Chrome extensions by searching LevelDB files for identifiable keywords like “gauth” or “authenticator”.

Each method attempts to locate relevant files, parse or partially read their contents, and store them in a dictionary under labels like authy, microsoft_auth, or chrome_extension. However, as before, this is limited to Windows, and there is no handling for encrypted tokens.

Enterprise Collector

The ‘EnterpriseCollector’ class is used to extract credentials related to an enterprise Windows system. It targets configuration and credential data from:

  • VPN clients
    • Cisco AnyConnect, OpenVPN, Forticlient, Pulse Secure
  • RDP credentials
  • Corporate certificates
  • Active Directory tokens
  • Kerberos tickets cache

The files and directories are located based on standard environment variables with their contents read in binary mode and then encoded in Base64.

Super Extended Application Collector

The ‘SuperExtendedApplication’ Collector class is designed to scan an environment for 160 different applications on a Windows system. It iterates through the paths of a wide range of software categories including messaging apps, cryptocurrency wallets, password managers, development tools, enterprise tools, gaming clients, and security products. The list includes but is not limited to Teams, Slack, Mattermost, Zoom, Google Meet, MS Office, Defender, Norton, McAfee, Steam, Twitch, VMWare, to name a few.

Bypass

AppBoundBypass

This code outlines a framework for bypassing App Bound protections, Google Chrome' s cookie encryption. The ‘AppBoundBypass’ class attempts several evasion techniques, including memory injection, dynamic-link library (DLL) hijacking, process hollowing, atom bombing, and process doppelgänging to impersonate or hijack browser processes. As of the time of writing, the code contains multiple placeholders, indicating that the code is still in development.

Steganography

The ‘SteganographyModule’ uses steganography (hiding data within an image) to hide the stolen data, staging it for exfiltration. Multiple methods are implemented, including:

  • Image steganography: LSB-based hiding
  • NTFS Alternate Data Streams
  • Windows Registry Keys
  • Slack space: Writing into unallocated disk cluster space
  • Polyglot files: Appending archive data to images
  • Image metadata: Embedding data in EXIF tags
  • Whitespace encoding: Hiding binary in trailing spaces of text files

Exfiltration

CloudProxy

Screenshot of the ‘CloudProxy’ class.
Figure 8: Screenshot of the ‘CloudProxy’ class.

The CloudProxy class is designed for exfiltrating data by routing it through cloud service domains. It encodes the input data using Base64, attaches a timestamp and SHA-256 signature, and attempts to send this payload as a JSON object via HTTP POST requests to cloud URLs including AWS, GCP, and Azure, allowing the traffic to blend in. As of the time of writing, these public facing URLs do not accept POST requests, indicating that they are placeholders meant to be replaced with attacker-controlled cloud endpoints in a finalized build.

P2PEngine

Screenshot of the P2PEngine.
Figure 9: Screenshot of the P2PEngine.

The ‘P2PEngine’ provides multiple methods of C2, including embedding instructions within blockchain transactions (such as Bitcoin OP_RETURN, Ethereum smart contracts), exfiltrating data via anonymizing networks like Tor and I2P, and storing payloads on IPFS (a distributed file system). It also supports domain generation algorithms (DGA) to create dynamic .onion addresses for evading detection.

After a compromise, the stealer creates both HTML and TXT reports containing the stolen data. It then sends these reports to the attacker’s designated Telegram account.

Xillen Killers

 Xillen Killers.
FIgure 10: Xillen Killers.

Xillen Stealer appears to be developed by a self-described 15-year-old “pentest specialist” “Beng/jaminButton” who creates TikTok videos showing basic exploits and open-source intelligence (OSINT) techniques. The group distributing the information stealer, known as “Xillen Killers”, claims to have 3,000 members. Additionally, the group claims to have been involved in:

  • Analysis of Project DDoSia, a tool reportedly used by the NoName057(16) group, revealing that rather functioning as a distributed denial-of-service (DDos) tool, it is actually a remote access trojan (RAT) and stealer, along with the identification of involved individuals.
  • Compromise of doxbin.net in October 2025.
  • Discovery of vulnerabilities on a Russian mods site and a Ukrainian news site

The group, which claims to be part of the Russian IT scene, use Telegram for logging, marketing, and support.

Conclusion

While some components of XillenStealer remain underdeveloped, the range of intended feature set, which includes credential harvesting, cryptocurrency theft, container targeting, and anti-analysis techniques, suggests that once fully developed it could become a sophisticated stealer. The intention to use AI to help improve targeting in malware campaigns, even though not yet implemented, indicates how threat actors are likely to incorporate AI into future campaigns.  

Credit to Tara Gould (Threat Research Lead)
Edited by Ryan Traill (Analyst Content Lead)

Appendicies

Indicators of Compromise (IoCs)

395350d9cfbf32cef74357fd9cb66134 - confid.py

F3ce485b669e7c18b66d09418e979468 - stealer_v5_ultimate.py

3133fe7dc7b690264ee4f0fb6d867946 - xillen_v5.exe

https://github[.]com/BengaminButton/XillenStealer

https://github[.]com/BengaminButton/XillenStealer/commit/9d9f105df4a6b20613e3a7c55379dcbf4d1ef465

MITRE ATT&CK

ID Technique

T1059.006 - Python

T1555 - Credentials from Password Stores

T1555.003 - Credentials from Password Stores: Credentials from Web Browsers

T1555.005 - Credentials from Password Stores: Password Managers

T1649 - Steal or Forge Authentication Certificates

T1558 - Steal or Forge Kerberos Tickets

T1539 - Steal Web Session Cookie

T1552.001 - Unsecured Credentials: Credentials In Files

T1552.004 - Unsecured Credentials: Private Keys

T1552.005 - Unsecured Credentials: Cloud Instance Metadata API

T1217 - Browser Information Discovery

T1622 - Debugger Evasion

T1082 - System Information Discovery

T1497.001 - Virtualization/Sandbox Evasion: System Checks

T1115 - Clipboard Data

T1001.002 - Data Obfuscation: Steganography

T1567 - Exfiltration Over Web Service

T1657 - Financial Theft

Continue reading
About the author
Tara Gould
Threat Researcher
Your data. Our AI.
Elevate your network security with Darktrace AI