CVE-2026-101917 (GCVE-0-2026-101917)

Vulnerability from cvelistv5 – Published: 2026-09-28 20:07 – Updated: 2026-09-28 20:35
VLAI
Title
PyJWT: PyJWKClient still amplifies unauthenticated JWKS fetches on unknown kid values (incomplete fix of CVE-2026-48524)
Summary
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT get_signing_key_from_jwt is affected because unknown kid misses force refreshes without a negative cache or minimum refresh interval. This occurs when unauthenticated tokens repeatedly use the same unknown kid or varying kid values absent from the cached JWKS. As a result, each cache miss causes PyJWKClient to refresh the JWKS. Consequently, attacker traffic can amplify outbound requests to the configured JWKS endpoint. This issue is fixed in version 2.14.0.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-28 20:35 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 7861 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
jpadilla pyjwt Affected: < 2.14.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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