Critical Malicious Code Vulnerability in test-workalendar-internal Package
Summary
MAL-2026-18092: Malicious code in test-workalendar-internal (PyPI). Affects test-workalendar-internal versions 0.0.1 – 0.0.3. No fix is published. How to fix ↓
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Background
The test-workalendar-internal package, available on PyPI, is designed to provide internal functionalities related to work calendars. It is utilized by developers to manage and manipulate calendar data efficiently. However, this package has been compromised, exposing users to significant security risks due to malicious code embedded within it.
Vulnerability Detail
The vulnerability originates from a malicious actor who has modified the package to include a backdoor. During the installation process, the package overrides the install command in setup.py, executing harmful code that creates a web-sharable terminal session. This session is then exposed via a Cloudflare tunnel, allowing the attacker to gain unauthorized access to the user's system. The ramifications of this vulnerability are severe, as it can lead to data breaches and unauthorized control over the affected systems.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall test-workalendar-internalIf 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 test-workalendar-internal package until a secure version is released. Additionally, consider using alternative packages that provide similar functionalities without the associated risks.
Conclusion
The test-workalendar-internal package has been compromised with malicious code that poses significant security risks to users. It is essential to take immediate action by uninstalling the package and monitoring for updates. Utilizing tools like Vulert can help in identifying and managing vulnerabilities effectively.
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FAQ
The vulnerability involves malicious code that creates a backdoor, allowing unauthorized access to the user's system.
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Uninstall the test-workalendar-internal package immediately and monitor for any patched versions to update.
Yes, consider using other packages that offer similar functionalities without the security risks associated with test-workalendar-internal.
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References
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