Malicious Code Vulnerability in workcalender Package
Summary
MAL-2026-18093: Malicious code in workcalender (PyPI). Affects workcalender versions 17.1.0.dev0. No fix is published. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Background
The workcalender package, available on PyPI, is designed to assist users in managing and organizing calendar events. It is intended for developers looking to integrate calendar functionalities into their applications. However, this package has been flagged for potential malicious intent, as it contains a stub build-time helper that could lead to backdoor installations, exploiting dependency confusion.
Vulnerability Detail
The vulnerability originates from the package's upload by a user known as kam193, who has previously been associated with malicious packages. Although the current version of workcalender does not contain explicit malicious code, it is suspected to be designed for future exploitation. The package overrides the install command in setup.py to execute potentially harmful code during installation, posing a significant risk to users who install it.
How To Fix
This package is malicious. Remove it and rotate any credentials it could have accessed.
pip uninstall workcalenderIf it arrived as a transitive dependency, remove the package that pulled it in, then reinstall.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
As a temporary measure, you can avoid installing the workcalender package. If you need similar functionality, consider using alternative packages that are well-reviewed and have a history of security compliance. Always verify the integrity of packages before installation.
Conclusion
The workcalender package has been identified as potentially malicious due to its design and the intentions of its uploader. Users are advised to avoid using this package and to seek alternatives until a secure version is released. Regular monitoring for vulnerabilities using tools like Vulert can help maintain the security of your applications.
See every vulnerability recorded for workcalender →
FAQ
The workcalender package is a Python library designed to help developers manage calendar events within their applications.
The vulnerability involves potential malicious code that could be executed during the installation of the package, as it overrides the install command in setup.py.
You can use Vulert, which monitors and alerts for open-source vulnerabilities in real-time. Visit Vulert Scanner to check your application without needing to sign up.
If you have installed the workcalender package, it is advisable to remove it from your project and monitor for any updates or patches.
Yes, consider using other well-reviewed calendar management packages available on PyPI that do not have known vulnerabilities.
