Malicious Code Exfiltration in composer-dev Package
Summary
MAL-2026-1987: Malicious code in composer-dev (PyPI). Affects composer-dev versions 9.9.9. No fix is published. How to fix ↓
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Background
The composer-dev package, available on PyPI, is intended for development purposes within Python environments. It is designed to assist developers in managing dependencies and enhancing their workflow. However, this package has been identified as malicious, containing code that exfiltrates sensitive information from the host system, such as IP addresses and usernames, posing a significant security risk to users who install it.
Vulnerability Detail
The vulnerability stems from the malicious code embedded in the composer-dev package, which overrides the install command in setup.py to execute harmful actions during installation. This code is designed to exfiltrate basic information about the host, making it a potential threat to user privacy and security. The package has no legitimate functionality beyond this malicious intent, and its installation can lead to unauthorized data access.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall composer-devIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
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Workaround
There are no specific workarounds for this vulnerability, as the best course of action is to completely avoid the use of the composer-dev package. If you need similar functionality, consider using alternative packages that are well-reviewed and have a good security track record.
Conclusion
The composer-dev package poses a significant security risk due to its malicious code that exfiltrates sensitive information from the host system. Users are advised to uninstall this package and avoid using it in the future. Regular monitoring of open-source vulnerabilities using tools like Vulert can help maintain the security of your applications.
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FAQ
The composer-dev package is a Python package intended for development purposes, but it has been identified as malicious.
The malicious code in the composer-dev package exfiltrates basic information such as the host's IP address and username.
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Currently, there is no safe or patched version of the composer-dev package available. It is recommended to avoid using it.
If you have installed composer-dev, you should uninstall it immediately using the command 'pip uninstall composer-dev'.
