CVE-2026-32597

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f	Exploit Mitigation Vendor Advisory
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-13 19:55

Updated : 2026-03-19 13:30

NVD link : CVE-2026-32597

Mitre link : CVE-2026-32597

CVE.ORG link : CVE-2026-32597

JSON object : View

Products Affected

pyjwt_project

pyjwt

CWE

CWE-345

Insufficient Verification of Data Authenticity

CWE-863

Incorrect Authorization

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