Cybersecurity experts have discovered several malicious packages on the Python Package Index (PyPI) that deliver the WhiteSnake Stealer malware, specifically targeting Windows systems.
These packages, uploaded under various names by a threat actor known as “WS,” contain Base64-encoded source code in their setup.py files, leading to the installation of the malware upon package installation.
The malware is designed to steal information from Windows users, including data from web browsers, cryptocurrency wallets, and various applications, and also has an Anti-VM mechanism and communicates with its command and control server using the Tor protocol.
The threat actor behind this campaign, dubbed PYTA31 by Checkmarx, aims to exfiltrate sensitive data, particularly from crypto wallets. Some of these malicious packages also have clipper functionality, allowing them to overwrite clipboard content with the attacker’s wallet addresses to facilitate unauthorized transactions.
In addition to targeting crypto wallets, these packages are configured to steal data from browsers and other applications. This incident highlights the growing trend of malware authors infiltrating open-source repositories like PyPI with info-stealing malware, showcasing the sophistication and persistence of these threat actors.
Each malware package exhibits unique payload characteristics, underlining the evolving nature of these cyber threats. In a related discovery, ReversingLabs found malicious packages on the npm package registry that use GitHub to store stolen SSH keys.
These keys are encrypted in Base64 and extracted from developer systems where the malicious npm packages are installed. This demonstrates the widespread and increasingly sophisticated methods employed by cybercriminals to target various software ecosystems.