MAL-2026-3251 Malicious code in puan31 (PyPI)
Malicious package
Published
MAL-2026-3251 is a malicious package: puan31 (PyPI). Every version was published to cause harm.
Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.
Reference: https://insights.sbomify.com/MAL-2026-3251/ (Markdown: https://insights.sbomify.com/MAL-2026-3251/index.md)
- Package
- puan31
- Registry
- PyPI
What is MAL-2026-3251?
MAL-2026-3251 is a malicious package in puan31, published on 3 May 2026.
Official description
During import, package automatically starts a connection to a C2 server, exfiltrates information about the host and data like the browser's history and sensitive files, and then waits for remote commands to execute.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-05-puan3
Reasons (based on the campaign):
exfiltration-generic
exfiltration-browser-data
The package contains code to execute remote commands (probably limited to a specific set) on the victim's machine.
exfiltration-credentials
rat
What should I do about MAL-2026-3251?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.