CVE-2025-66418 (GCVE-0-2025-66418)
Vulnerability from cvelistv5
Published
2025-12-05 16:02
Modified
2025-12-05 18:15
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
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
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.
References
Impacted products
Vendor Product Version
urllib3 urllib3 Version: >= 1.24, < 2.6.0
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