CVE-2026-32597highCWE-345CWE-347CWE-863

CVE-2026-32597: high-severity vulnerability in jpadilla pyjwt

PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Affected products
jpadilla · pyjwt
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