Malicious Code Execution Vulnerability in ssemver Package
Summary
MAL-2026-18119: Malicious code in ssemver (PyPI). Affects ssemver versions 1.0.0. No fix is published. How to fix ↓
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Background
The ssemver package is a Python library available on PyPI that is designed for semantic versioning. It allows developers to manage versioning in their applications effectively. However, this package has been compromised, leading to a significant security vulnerability that poses risks to users who install it.
Vulnerability Detail
The vulnerability originates from a malicious code embedded in the ssemver package, specifically in version 1.0.0. During installation, the package downloads and executes malware from a remote server, which can lead to unauthorized access and potential data breaches. The malicious intent is clear, as it is part of a campaign that involves typosquatting and the distribution of infostealers.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall ssemverIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
As a temporary workaround, users can avoid using the ssemver package until a secure version is released. Alternatively, consider using other semantic versioning libraries that are known to be secure.
Conclusion
The ssemver package has been compromised, leading to a serious vulnerability that can execute malicious code on user systems. It is crucial for users to uninstall the affected version and monitor their systems for any unusual activity. Utilizing tools like Vulert can help in identifying and managing such vulnerabilities effectively.
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FAQ
ssemver is a Python library for managing semantic versioning in applications.
The vulnerability allows malicious code to be executed on your system, potentially leading to data theft or unauthorized access.
Uninstall the ssemver package immediately and monitor your system for any suspicious activity.
Yes, you can use Vulert's playground at Vulert Scanner to check if your application is affected by this vulnerability without needing to sign up.
Regularly monitor your dependencies for vulnerabilities using tools like Vulert, which alerts you in real-time for open-source vulnerabilities.
