CVE-2025-71321: picklescan - Arbitrary File Writing via distutils Module Bypass

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-17 · updated 2026-10-12
Weakness: CWE-502

Description

picklescan before 0.0.33 contains an arbitrary file writing vulnerability that allows attackers to bypass the dangerous blocklist by using distutils.file_util.write_file. Attackers can construct malicious pickle objects to overwrite critical system files and achieve denial of service or remote code execution.

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-m273-6v24-x4m4
https://www.vulncheck.com/advisories/picklescan-arbitrary-file-writing-via-distutils-module-bypass
https://github.com/mmaitre314/picklescan/security/advisories/GHSA-m273-6v24-x4m4

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