PYSEC-2026-120

At a glance

Published: 2026-03-13 19:55 UTC
Updated: 2026-05-20 09:19 UTC
CVE: CVE-2026-32597
Aliases: GHSA-752w-5fwx-jx9f
CVSS_V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

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.

Affected packages

Package	Versions
PyPI · pyjwt	introduced 0, fixed 2.12.0

References

https://lists.debian.org/debian-lts-announce/2026/05/msg00008.html WEB
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f EVIDENCE

Sources

Source	Licence
OSV.dev	CC-BY 4.0 — PyPA Advisory Database