pycacheopt

GHSA-v774-59vp-jmqg

Malicious code in pycacheopt (PyPI)

Details

**Severity:** Critical

**Affected versions:** `= 0.2.1`

## Source: kam193 (cf50eae305079227b5283e08547cc201f941624c95e49460c3e6544cdd1e221b)
The extension module hides code that in specific circumstances executes given code. The malicious action is hidden only in the extension module with the same-named Python code file containing only benign code.

This campaign was first detected by Aikido Security.


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Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.


Campaign: 2026-05-pycacheopt


Reasons (based on the campaign):


 - other


 - The package contains code to detect if it is running in a sandbox environment.

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Credit: [OpenSSF](https://github.com/ossf/malicious-packages) ([source](https://github.com/ossf/malicious-packages/blob/49d0cfba3689ed9b195d101d3a2a964c6a77f767/osv/malicious/pypi/pycacheopt/MAL-2026-3371.json))

**References:**
- https://app.aikido.dev/reports/malware/software-supply-chain-attacks?packageId=934457
- https://bad-packages.kam193.eu/pypi/package/pycacheopt
- https://github.com/ossf/malicious-packages/blob/49d0cfba3689ed9b195d101d3a2a964c6a77f767/osv/malicious/pypi/pycacheopt/MAL-2026-3371.json
- https://github.com/advisories/GHSA-v774-59vp-jmqg

Compromised versions (1)

= 0.2.1

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