CVE-2025-67747: PYSEC-2026-1368 - Fickling has missing detection for marshal.loads and types.FunctionType in unsafe modules list

CVE-2025-67747 · Severity: high · CVSS 7.8 · Published 2025-12-16

Fickling is a Python pickling decompiler and static analyzer. Versions prior to 0.1.6 are missing `marshal` and `types` from the block list of unsafe module imports. Fickling started blocking both modules to address this issue. This allows an attacker to craft a malicious pickle file that can bypass fickling since it misses detections for `types.FunctionType` and `marshal.loads`. A user who deserializes such a file, believing it to be safe, would inadvertently execute arbitrary code on their system. This impacts any user or system that uses Fickling to vet pickle files for security issues. The issue was fixed in version 0.1.6.

Technologies: fickling (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2025-67747 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-67747 being exploited in the wild.
How severe is CVE-2025-67747?
High severity, with a CVSS score of 7.8, published 16 December 2025.
Which products and versions are affected?
fickling (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.6.
Is there a fix for CVE-2025-67747?
Yes. fickling (PyPI): upgrade to 0.1.6 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2025-67747?
Check whether you run fickling (PyPI) or Trailofbits Fickling at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • fickling (PyPI): upgrade to 0.1.6 or later
    pip install "fickling>=0.1.6"

Affected products

  • fickling (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.6
  • Trailofbits Fickling

Identifiers

  • CVE-2025-67747
  • GHSA-565g-hwwr-4pp3
  • PYSEC-2026-1368

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