Malicious Code Exfiltration in metadata-checker Package
Summary
MAL-2026-762: Malicious code in metadata-checker (PyPI). Affects metadata-checker versions 1.2.0. No fix is published. How to fix ↓
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Background
The metadata-checker package, available on PyPI, is designed to validate and manage metadata for Python packages. It is intended to assist developers in ensuring that their package metadata is correctly formatted and compliant with standards. However, a recent vulnerability has been identified that allows malicious actors to exfiltrate sensitive data from users' systems.
Vulnerability Detail
The vulnerability originates from a malicious campaign disguised as a legitimate metadata checker. The package, created by the user kam193, is designed to exfiltrate hardcoded or user-provided data to an obfuscated remote server. This poses significant risks, including unauthorized data access and potential data breaches, as the malicious code can operate without the user's knowledge.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall metadata-checkerIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary measure, users can avoid using the metadata-checker package until a secure version is released. Additionally, consider using alternative packages that provide similar functionality without the associated risks.
Conclusion
The metadata-checker package has been identified as containing malicious code that can exfiltrate sensitive data. Users are advised to uninstall the package and monitor for updates. Utilizing tools like Vulert can help in identifying vulnerabilities in your applications.
See every vulnerability recorded for metadata-checker →
FAQ
The metadata-checker package is a tool for validating and managing metadata for Python packages, ensuring compliance with standards.
The vulnerability allows malicious actors to exfiltrate sensitive data from users' systems, potentially leading to data breaches.
It is recommended to uninstall the metadata-checker package immediately and monitor for any updates regarding a secure version.
You can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.
Failure to address this vulnerability may result in unauthorized access to sensitive data, leading to data breaches and loss of user trust.
