Allocation of Resources Without Limits or Throttling The advisory has been revoked - it doesn't affect any version of package python-urllib3 (opens in a new tab)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-RHEL10-PYTHONURLLIB3-20072023
- published24 Sept 2026
- disclosed23 Sept 2026
Introduced: 23 Sep 2026
NewCVE-2026-59980 (opens in a new tab)Amendment
The Red Hat security team deemed this advisory irrelevant for RHEL:10.
NVD Description
Note: Versions mentioned in the description apply only to the upstream python-urllib3 package and not the python-urllib3 package as distributed by RHEL.
hpack is an HTTP/2 Header Encoding for Python. Prior to version 4.2.0, unbounded variable integer decoding can cause run-away computation on malformed input leading to O(n^2) runtime, effectively blocking further processing with large enough unsanitized input. A fix is available in python-hyper/hpack v4.2.0 to restricted variable integer decoding to uint32 to prevent run-away computation. As a workaround, sanitize input to hpack decoder for long sequences of 0xFF values to prevent malicious use.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=2539827
- https://access.redhat.com/security/cve/CVE-2026-59980
- https://cs.opensource.google/go/x/net/+/master:http2/hpack/hpack.go;l=468;drc=8e2b117aee74f6b86c207a808b0255de45c0a18a
- https://docs.rs/http2/0.5.19/src/http2/hpack/decoder.rs.html#403
- https://github.com/python-hyper/hpack/commit/8cfb02c547740e16dbfe7aba77bad84b297cec2c
- https://github.com/python-hyper/hpack/security/advisories/GHSA-8v8h-hg4w-mvq2