Vulnerability Description
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 Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Pyjwt Project | Pyjwt | < 2.12.0 |
Related Weaknesses (CWE)
References
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9fExploitMitigationVendor Advisory
- https://lists.debian.org/debian-lts-announce/2026/05/msg00008.html
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9fExploitMitigationVendor Advisory
FAQ
What is CVE-2026-32597?
CVE-2026-32597 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 li...
How severe is CVE-2026-32597?
CVE-2026-32597 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-32597?
Check the references section above for vendor advisories and patch information. Affected products include: Pyjwt Project Pyjwt.