MalwarePublished 30 Sep 2026

cleanup-string (PyPI) · Malicious Code

Affects cleanup-stringSource GCVE Database

Malicious package : remove cleanup-string and rotate any secrets on hosts that installed it.

Data as of 30 Sep 2026, 16:39 UTC

Classification

Malicious package

Published to PyPI · OSV MAL-2026-17325

What to do

Remove cleanup-string from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
PyPIcleanup-string	Affected =1.0.0	Fixed in–

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Description

The PyPI package 'cleanup-string' version 1.0.0 includes a suspicious Windows-only native extension protected by VMProtect, a tool used to obfuscate and virtualize code to prevent analysis. Although the package claims to be a pure-Python string helper, it loads a large opaque binary module with no clear legitimate purpose. This module executes with the privileges of the importing process in any Windows Python 3.13 environment, potentially enabling malicious activity.

Impact

Any Windows system running Python 3.13 that imports the 'cleanup-string' package version 1.0.0 will execute a large, obfuscated native binary with the same privileges as the Python process. This could lead to arbitrary code execution, privilege escalation, or other malicious actions depending on the hidden payload within the protected binary. The obfuscation and virtualization hinder detection and analysis, increasing risk.

Defensive guidance

Users should avoid installing or importing the 'cleanup-string' package version 1.0.0, especially on Windows systems running Python 3.13. Verify package integrity and source before use. Monitor for updates from the package maintainer or PyPI for any official fixes or removals.

Summary

The 'cleanup-string' PyPI package version 1.0.0 advertises simple string manipulation functionality implemented purely in Python. However, it loads a 1.3 MB Windows-only native extension named '_impl.cp313-win_amd64.vmp.pyd' that is protected by VMProtect, a known anti-analysis packer. The binary contains only Windows API imports and highly obfuscated virtualized code, inconsistent with the advertised functionality. This means that importing the package on Windows with Python 3.13 executes opaque native code with the importing process's privileges, representing a malicious package threat.

References

pypi.org/project/cleanup-string/1.0.0/ (opens in a new tab)

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What to do

Affected software

Description

AI analysisMachine-generated, updated 30 Sep 2026, 16:39 UTC

Technical details

References

Community reviews