CVE-2025-66418 (GCVE-0-2025-66418)

Vulnerability from cvelistv5 – Published: 2025-12-05 16:02 – Updated: 2025-12-05 18:15
VLAI
Title
urllib3 allows an unbounded number of links in the decompression chain
Summary
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.
Severity
8.9 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-12-05 16:15 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7797 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
urllib3 urllib3 Affected: >= 1.24, < 2.6.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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