QID 982695

QID 982695: Python (pip) Security Update for urllib3 (GHSA-hmv2-79q8-fv6g)

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2).

Successful exploitation of this vulnerability may affect the confidentiality, integrity, and availability of the targeted user.

  • CVSS V3 rated as High - 7.5 severity.
  • CVSS V2 rated as High - 7.8 severity.
  • Solution
    Customers are advised to refer to GHSA-hmv2-79q8-fv6g for updates pertaining to this vulnerability.
    Vendor References

    CVEs related to QID 982695

    Software Advisories
    Advisory ID Software Component Link
    GHSA-hmv2-79q8-fv6g urllib3 URL Logo github.com/advisories/GHSA-hmv2-79q8-fv6g
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