tosa-serialization-lib

GHSA-99cg-mqj9-7c7q

Malicious code in tosa-serialization-lib (PyPI)

Details

**Severity:** Critical

**Affected versions:** `= 2.0.0`

## Source: kam193 (5badd7c7414eb1f6fbdf1934b42ffe74549daa74508afd092af853097170eb8e)
Installing the package or importing the module exfiltrates basic information about the host, and the package has no other purpose.


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Category: PROBABLY_PENTEST - Packages looking like typical pentest packages, but also anything that looks like testing, exploring pre-prepared kits, research & co, with clearly low-harm possibilities.


Campaign: GENERIC-standard-pypi-install-pentest


Reasons (based on the campaign):


 - The package contains code to exfiltrate basic data from the system, like IP or username. It has a limited risk.


 - The package overrides the install command in setup.py to execute malicious code during installation.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/49d0cfba3689ed9b195d101d3a2a964c6a77f767/osv/malicious/pypi/tosa-serialization-lib/MAL-2025-191908.json))

**References:**
- https://bad-packages.kam193.eu/pypi/package/tosa-serialization-lib
- https://github.com/ossf/malicious-packages/blob/49d0cfba3689ed9b195d101d3a2a964c6a77f767/osv/malicious/pypi/tosa-serialization-lib/MAL-2025-191908.json
- https://github.com/advisories/GHSA-99cg-mqj9-7c7q

Compromised versions (1)

= 2.0.0

Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.