CVE-2025-66418 (High) detected in urllib3-1.26.20-py2.py3-none-any.whl

[mend-bolt-for-github]

CVE-2025-66418 - High Severity Vulnerability

Vulnerable Library - urllib3-1.26.20-py2.py3-none-any.whl

HTTP library with thread-safe connection pooling, file post, and more.

Library home page: https://files.pythonhosted.org/packages/33/cf/8435d5a7159e2a9c83a95896ed596f68cf798005fe107cc655b5c5c14704/urllib3-1.26.20-py2.py3-none-any.whl

Path to dependency file: /requirements/requirements.txt

Path to vulnerable library: /tmp/ws-ua_20260220174600_OJTTHD/python_CIVYXV/202602201746161/env/lib/python3.9/site-packages/urllib3-1.26.20.dist-info

Dependency Hierarchy:

• ❌ urllib3-1.26.20-py2.py3-none-any.whl (Vulnerable Library)

Found in HEAD commit: 18e84670c8f0bc1fa0d5934e39a695d712e94c0c

Found in base branch: main

Vulnerability Details

urllib3 is a user-friendly HTTP client library for Python. Starting in version 1.24 and prior to 2.6.0, the number of links in the decompression chain was unbounded allowing a malicious server to insert a virtually unlimited number of compression steps leading to high CPU usage and massive memory allocation for the decompressed data. This vulnerability is fixed in 2.6.0.

Publish Date: 2025-12-05

URL: CVE-2025-66418

CVSS 3 Score Details (8.6)

Base Score Metrics:

• Exploitability Metrics:
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Changed
• Impact Metrics:
  • Confidentiality Impact: None
  • Integrity Impact: None
  • Availability Impact: High

For more information on CVSS3 Scores, click here.

Suggested Fix

Type: Upgrade version

Release Date: 2025-12-05

Fix Resolution: https://github.com/urllib3/urllib3.git - 2.6.0,urllib3 - 2.6.0

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