CVE-2025-67747 HIGH

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

Vendor Trailofbits
Product fickling
Weakness CWE-184
Published December 16, 2025
Last update December 16, 2025

CVSS base score

7.1/10
Attack vector Local
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

December 16, 2025 CVE published
December 16, 2025 Record updated