CVE-2026-102269 (GCVE-0-2026-102269)

Vulnerability from cvelistv5 – Published: 2026-09-28 20:27 – Updated: 2026-09-29 13:49
VLAI
Title
PyJWT: Non-canonical signature segments enable raw-token revocation bypass
Summary
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, PyJWT signature segment is affected because signature segment decoding accepts characters outside the canonical Base64URL representation. This occurs when non-Base64URL characters are appended to a valid compact JWS signature segment. As a result, base64url_decode produces the same signature bytes for different serialized segments. Consequently, raw-token revocation checks can fail to recognize an equivalent modified token. This issue is fixed in version 2.14.0.
Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 13:48 UTC
CWE
  • CWE-180 - Incorrect Behavior Order: Validate Before Canonicalize
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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