CVE-2026-32597 (GCVE-0-2026-32597)

Vulnerability from cvelistv5 – Published: 2026-03-12 21:41 – Updated: 2026-03-13 14:58
VLAI?
Title
PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)
Summary
PyJWT is a JSON Web Token implementation in Python. Prior to 2.12.0, PyJWT does not validate the crit (Critical) Header Parameter defined in RFC 7515 §4.1.11. When a JWS token contains a crit array listing extensions that PyJWT does not understand, the library accepts the token instead of rejecting it. This violates the MUST requirement in the RFC. This vulnerability is fixed in 2.12.0.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-345 - Insufficient Verification of Data Authenticity
  • CWE-863 - Incorrect Authorization
Assigner
References
Impacted products
Vendor Product Version
jpadilla pyjwt Affected: < 2.12.0
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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