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Vulnerability record · CVE-2026-32597 · published 13 March 2026

CVE-2026-32597: Pyjwt project pyjwt insufficient verification of data authenticity vulnerability

Pyjwt Project · Pyjwt

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.

7.5 CVSS 3.1 High EPSS 0.28% · top 81.5% CWE-345 · Insufficient verification of data authenticityCWE-863 · Incorrect authorization
7.5CVSS 3.1 base score
0.28%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
36References, 2 tagged exploit
10 Sep 2026Last modified by NVD

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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f ExploitMitigationVendor Advisory
https://lists.debian.org/debian-lts-announce/2026/05/msg00008.html
https://access.redhat.com/errata/RHSA-2026:10140
https://access.redhat.com/errata/RHSA-2026:10141
https://access.redhat.com/errata/RHSA-2026:10184
https://access.redhat.com/errata/RHSA-2026:12176
https://access.redhat.com/errata/RHSA-2026:13508
https://access.redhat.com/errata/RHSA-2026:13512
https://access.redhat.com/errata/RHSA-2026:13545
https://access.redhat.com/errata/RHSA-2026:13553
https://access.redhat.com/errata/RHSA-2026:13672
https://access.redhat.com/errata/RHSA-2026:13916
https://access.redhat.com/errata/RHSA-2026:17083
https://access.redhat.com/errata/RHSA-2026:19138
https://access.redhat.com/errata/RHSA-2026:19355
https://access.redhat.com/errata/RHSA-2026:19375
https://access.redhat.com/errata/RHSA-2026:19712
https://access.redhat.com/errata/RHSA-2026:21431
https://access.redhat.com/errata/RHSA-2026:21517
https://access.redhat.com/errata/RHSA-2026:22330
https://access.redhat.com/errata/RHSA-2026:24977
https://access.redhat.com/errata/RHSA-2026:26226
https://access.redhat.com/errata/RHSA-2026:37275
https://access.redhat.com/errata/RHSA-2026:42644
https://access.redhat.com/errata/RHSA-2026:6568
https://access.redhat.com/errata/RHSA-2026:6720
https://access.redhat.com/errata/RHSA-2026:6912
https://access.redhat.com/errata/RHSA-2026:6926
https://access.redhat.com/errata/RHSA-2026:8437
https://access.redhat.com/errata/RHSA-2026:8746
https://access.redhat.com/errata/RHSA-2026:8747
https://access.redhat.com/errata/RHSA-2026:8748
https://access.redhat.com/security/cve/CVE-2026-32597
https://bugzilla.redhat.com/show_bug.cgi?id=2447194
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-752w-5fwx-jx9f ExploitMitigationVendor Advisory
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-32597.json

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Source: NIST National Vulnerability Database (record CVE-2026-32597), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.