Xillen Stealer is a Python-based cross-platform information stealer whose v4 and v5 updates expand capabilities to harvest credentials, browser data from 100+ browsers, cryptocurrency from 70+ wallets, container and cloud configurations, and biometric/TOTP data while adding persistence, polymorphism, and P2P C2 features. The malware is marketed via Telegram by a group calling itself Xillen Killers and has public GitHub activity and sample hashes published in the appendices. #XillenStealer #XillenKillers
Keypoints
- Xillen Stealer v4/v5 is a Python-based infostealer targeting credentials, browser data, cryptocurrency wallets, system information, and biometric/TOTP artifacts across multiple platforms.
- New functionality includes persistence, Kubernetes/Docker scanning, container credential collection, cloud API exfiltration via a CloudProxy, and P2P command-and-control mechanisms (including blockchain and IPFS options).
- Anti-analysis and evasion features comprise an AIEvasionEngine (behavioral mimicry, timing/randomization, API call and memory obfuscation), polymorphic Rust engine, and multiple planned process-injection and bypass techniques.
- Collectors target developer and cloud tooling (IDE configs, AWS/GCP/Azure credentials), password managers (OnePass, LastPass, BitWarden, Dashlane, NordPass, KeePass), SSH keys, SSO tokens, Kerberos tickets, and Windows biometric stores.
- Exfiltration methods include steganography, NTFS ADS, whitespace encoding, cloud-service routing for blend-in traffic, Telegram reporting for stolen data, and support for DGA/.onion and anonymizing networks for C2.
- The malware is commercially marketed on Telegram with a GUI for buyers; source code and commits have been posted to a public GitHub repository and multiple sample hashes are listed in the appendices.
MITRE Techniques
- [T1059.006 ] Python â Xillen Stealer is implemented in Python and uses Python-based components to run stealing routines (âPython-based information stealer âXillen Stealerââ)
- [T1555 ] Credentials from Password Stores â The stealer collects credentials from multiple stores and password managers (âAbility to steal credentials from password managersâ)
- [T1555.003 ] Credentials from Web Browsers â The malware harvests browser data including history, cookies and saved passwords from many browsers (âbrowser data (history, cookies and passwords) from over 100 browsersâ)
- [T1555.005 ] Credentials from Password Managers â Targets specific password managers to extract stored credentials (âOnePass, LastPass, BitWarden, Dashlane, NordPass and KeePassâ)
- [T1649 ] Steal or Forge Authentication Certificates â The enterprise collector targets corporate certificates for credential or identity theft (âcorporate certificatesâ)
- [T1558 ] Steal or Forge Kerberos Tickets â SSOCollector attempts to obtain Kerberos tickets via system commands for authentication theft (âKerberos tickets obtained through the klist commandâ)
- [T1539 ] Steal Web Session Cookie â The stealer collects web session cookies as part of browser data harvesting (âbrowser data (history, cookies and passwords) from over 100 browsersâ)
- [T1552.001 ] Unsecured Credentials: Credentials in Files â The tool scans files and config artifacts (e.g., .env) to harvest API keys and other credentials (âAPI keys from .env filesâ)
- [T1552.004 ] Unsecured Credentials: Private Keys â Xillen scans for key material such as SSH keys and private key files (âSSH keysâ)
- [T1552.005 ] Unsecured Credentials: Cloud Instance Metadata API â The malware targets cloud credentials and may abuse cloud metadata/APIs for credential access and exfiltration (âCloud credentials and configurationsâ / âexfiltrating data via Cloud APIsâ)
- [T1217 ] Browser Information Discovery â The stealer enumerates installed browsers and harvests stored browser artifacts (âsteal credentials ⌠browser data (history, cookies and passwords) from over 100 browsersâ)
- [T1622 ] Debugger Evasion â Code includes modules and placeholders intended to evade debugging and analysis (API obfuscation and behavior mimicry) (âAIEvasionEngine is a module designed to help malware evade AI-based or behavior-based detection systems, such as EDRs and sandboxesâ)
- [T1082 ] System Information Discovery â Xillen collects system and environment information to profile victims and prioritize targets (âsteal cryptocurrency, credentials, system information, and account informationâ)
- [T1497.001 ] Virtualization/Sandbox Evasion: System Checks â The evasion engine includes system checks and timing/randomization to avoid sandbox detection (âmimics legitimate user and system behaviorâŚrandomizes execution patternsâ)
- [T1115 ] Clipboard Data â The listed MITRE mappings include clipboard collection capability as part of the stealerâs data collection set (âT1115 â Clipboard Dataâ)
- [T1001.002 ] Data Obfuscation: Steganography â The stealer implements multiple steganography methods to hide data within images and other carriers before exfiltration (âThe SteganographyModule uses steganography (hiding data within an image)â)
- [T1567 ] Exfiltration Over Web Service â CloudProxy routes stolen data through cloud service domains using HTTP POST to blend traffic with legitimate cloud services (âexfiltrating data by routing it through cloud service domainsâ)
- [T1657 ] Financial Theft â A central goal is stealing cryptocurrency and other financial assets from wallets and related applications (âAbility to steal ⌠cryptocurrency from over 70 walletsâ)
Indicators of Compromise
- [File Hash ] malware samples â 395350d9cfbf32cef74357fd9cb66134 (confid.py), F3ce485b669e7c18b66d09418e979468 (stealer_v5_ultimate.py), and 1 more hash
- [File Name ] observed sample filenames â xillen_v5.exe, stealer_v5_ultimate.py (mapped to reported hashes)
- [Repository URL ] developer/distribution links â https://github[.]com/BengaminButton/XillenStealer, https://github[.]com/BengaminButton/XillenStealer/commit/9d9f105df4a6b20613e3a7c55379dcbf4d1ef465
- [File Paths ] targeted system artifacts â C:WindowsSystem32WinBioDatabase (Windows biometric DB), TokenBrokerCache (Azure AD token cache)
- [Cloud Services ] exfiltration/cover domains â AWS, GCP, Azure cloud domains used as CloudProxy placeholders for data exfiltration attempts
Read more: https://www.darktrace.com/blog/xillen-stealer-updates-to-version-5-to-evade-ai-detection