High severity · published Mar 12, 2026
CVE-2026-32597
PyJWT accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)
7.5
CVSS
0.3%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 20% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PY
pyjwt · jpadilla
< 2.12.0 · source: vendor, NVD
OL
OpenShift Lightspeed · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat AI Inference Server 3.3 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 8 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.5 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Ansible Automation Platform 2.6 for RHEL 9 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10 · Red Hat
All versions, or not specified · source: CISA
RH
Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat
All versions, or not specified · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-32597
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-32597
Exploit
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/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-2026:12176
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