---
id: CVE-2025-67747
title: Fickling is a Python pickling decompiler and static analyzer
summary: >-
  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 allo…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-184
  - CWE-502
vendor: trailofbits
product: fickling
affected:
  - fickling < 0.1.6
patched:
  - fickling 0.1.6
published: '2025-12-16'
updated: '2026-10-07'
sourceUpdated: '2026-10-07T19:10:00.160'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2025-67747'
references:
  - url: >-
      https://github.com/trailofbits/fickling/commit/4e34561301bda1450268d1d7b0b2b151de33b913
    label: security-advisories@github.com
  - url: 'https://github.com/trailofbits/fickling/pull/186'
    label: security-advisories@github.com
  - url: 'https://github.com/trailofbits/fickling/releases/tag/v0.1.6'
    label: security-advisories@github.com
  - url: >-
      https://github.com/trailofbits/fickling/security/advisories/GHSA-565g-hwwr-4pp3
    label: security-advisories@github.com
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2025-67747'
  - url: 'https://github.com/trailofbits/fickling'
tags:
  - nvd
  - osv
  - pip
epss: 0.00278
epssPercentile: 0.20149
aliases:
  - GHSA-565g-hwwr-4pp3
  - PYSEC-2026-1368
ecosystem: pip
ingestedAt: '2026-07-08T18:25:45.791Z'
---

## Overview

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.

## Affected

- `fickling < 0.1.6`

## Remediation

Upgrade past the affected range:

- `fickling 0.1.6`

## Package advisory (CVE-2025-67747)

Affected packages:

- `fickling < 0.1.6`

Patched in:

- `fickling 0.1.6`

Source: https://osv.dev/vulnerability/GHSA-565g-hwwr-4pp3