Malicious Code Exfiltration in arrayvec Package
Summary
MAL-2026-877: Malicious code in arrayvec (PyPI). Affects arrayvec versions 1.0.99. No fix is published. How to fix ↓
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Background
The arrayvec package is a Python library available on PyPI, designed to provide a dynamic array implementation. It is commonly used in various applications for efficient memory management and performance. However, this package has been identified to contain malicious code that compromises user data.
Vulnerability Detail
The vulnerability originates from a malicious actor who has embedded code within the arrayvec package that exfiltrates sensitive information from the host system, such as the IP address and username. This code is executed during the installation process due to the package overriding the install command in setup.py. The risk is categorized as low, but it poses a significant threat to user privacy and security.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall arrayvecIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary measure, avoid installing the arrayvec package until a patched version is confirmed. If you have already installed it, consider removing it immediately and monitoring your system for any unusual activity.
Conclusion
The arrayvec package has been compromised with malicious code that can exfiltrate user data. It is crucial to uninstall the affected version and update to a safe version to protect your system. Utilizing tools like Vulert can help monitor and alert for such vulnerabilities in real-time.
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FAQ
arrayvec is a Python library that provides a dynamic array implementation, commonly used for efficient memory management.
The vulnerability allows malicious code to exfiltrate sensitive information from your system during the installation of the package.
Uninstall the affected version immediately and update to a patched version using the provided commands.
Yes, you can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time without requiring code access.
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