GHSA-6556-fwc2-fg2p

Source

https://github.com/advisories/GHSA-6556-fwc2-fg2p

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/12/GHSA-6556-fwc2-fg2p/GHSA-6556-fwc2-fg2p.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-6556-fwc2-fg2p

Published

2025-12-30T15:20:14Z

Modified

2025-12-30T15:37:26.366809Z

Severity

6.7 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P CVSS Calculator

Summary

Picklescan is vulnerable to RCE through missing detection when calling numpy.f2py.crackfortran._eval_length

Details

Summary

Picklescan uses the numpy.f2py.crackfortran._eval_length function (a NumPy F2PY helper) to execute arbitrary Python code during unpickling.

Details

Picklescan fails to detect a malicious pickle that uses the gadget numpy.f2py.crackfortran._eval_length in __reduce__, allowing arbitrary command execution when the pickle is loaded. A crafted object returns this function plus attacker‑controlled arguments; the scan reports the file as safe, but pickle.load() triggers execution.

PoC

class PoC:
    def __reduce__(self):
        from numpy.f2py.crackfortran import _eval_length
        return _eval_length, ("__import__('os').system('whoami')", None)

Impact

Arbitrary code execution on the victim machine once they load the “scanned as safe” pickle / model file.
Affects any workflow relying on Picklescan to vet untrusted pickle / PyTorch artifacts.
Enables supply‑chain poisoning of shared model files.

Credits

ac0d3r
Tong Liu, Institute of information engineering, CAS

Database specific

{
    "nvd_published_at": null,
    "cwe_ids": [
        "CWE-502",
        "CWE-94"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2025-12-30T15:20:14Z"
}

References

Affected packages

PyPI / picklescan

Package

Name: picklescan; View open source insights on deps.dev
Purl: pkg:pypi/picklescan

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

0.0.33

Affected versions

0.*

0.0.1

0.0.2

0.0.3

0.0.4

0.0.5

0.0.6

0.0.7

0.0.8

0.0.9

0.0.10

0.0.11

0.0.12

0.0.13

0.0.14

0.0.15

0.0.16

0.0.17

0.0.18

0.0.19

0.0.20

0.0.21

0.0.22

0.0.23

0.0.24

0.0.25

0.0.26

0.0.27

0.0.28

0.0.29

0.0.30

0.0.31

0.0.32