CVE-2025-71339: Picklescan - Arbitrary Code Execution via numpy.f2py.crackfortran._eval_length Gadget

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-22 · updated 2026-10-12
Weakness: CWE-502

Description

Picklescan before 0.0.33 fails to detect the numpy.f2py.crackfortran._eval_length gadget in pickle __reduce__ methods, allowing arbitrary code execution. Attackers can craft malicious pickle files that execute arbitrary Python code when loaded by victims who trust Picklescan's safety validation.

Affected products

picklescan: before 0.0.33 — fixed in 0.0.33

How to fix

Upgrade to a fixed version: picklescan 0.0.33. Check the vendor advisory for mitigations.

References

https://github.com/mmaitre314/picklescan/security/advisories/GHSA-6556-fwc2-fg2p
https://www.vulncheck.com/advisories/picklescan-arbitrary-code-execution-via-numpy-f2py-crackfortran-eval-length-gadget
https://github.com/mmaitre314/picklescan/security/advisories/GHSA-6556-fwc2-fg2p

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