CVE-2026-32597
PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)
CVSS Score
7.5
EPSS Score
0.3%
EPSS Percentile
19th
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.
| CWE | CWE-345 CWE-863 |
| Vendor | jpadilla |
| Product | pyjwt |
| Published | Mar 12, 2026 |
| Last Updated | Jul 22, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
Affected Versions
jpadilla / pyjwt
< 2.12.0
References
github.com: https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f lists.debian.org: https://lists.debian.org/debian-lts-announce/2026/05/msg00008.html access.redhat.com: https://access.redhat.com/security/cve/CVE-2026-32597 bugzilla.redhat.com: https://bugzilla.redhat.com/show_bug.cgi?id=2447194 security.access.redhat.com: https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32597.json access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13512 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13508 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:17083 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13916 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:19138 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:12176 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:22330 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21517 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:21431 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13672 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:19355 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:8748 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:8746 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:8747 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13553 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:13545 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:10140 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:10141 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:10184 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:42644 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:24977 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:37275 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:19712 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:6720 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:6568 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:19375 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:6912 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:6926 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:26226 access.redhat.com: https://access.redhat.com/errata/RHSA-2026:8437