CVE-2026-102268

PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key as an HMAC secret. Consequently, an attacker who knows the public key can forge authenticated HMAC tokens. This issue is fixed in version 2.14.0.
Configurations

Configuration 1 (hide)

cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*

History

07 Oct 2026, 20:25

Type Values Removed Values Added
First Time Pyjwt Project pyjwt
Pyjwt Project
References () https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07 - () https://github.com/jpadilla/pyjwt/commit/8b4e233a22206b34ec1186e912e75c0b2396ac07 - Patch
References () https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 - () https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 - Product, Release Notes
References () https://github.com/jpadilla/pyjwt/security/advisories/GHSA-ffc3-869f-jxw9 - () https://github.com/jpadilla/pyjwt/security/advisories/GHSA-ffc3-869f-jxw9 - Exploit, Vendor Advisory
CPE cpe:2.3:a:pyjwt_project:pyjwt:*:*:*:*:*:*:*:*

29 Sep 2026, 14:17

Type Values Removed Values Added
References () https://github.com/jpadilla/pyjwt/security/advisories/GHSA-ffc3-869f-jxw9 - () https://github.com/jpadilla/pyjwt/security/advisories/GHSA-ffc3-869f-jxw9 -

28 Sep 2026, 21:17

Type Values Removed Values Added
New CVE

Information

Published : 2026-09-28 21:17

Updated : 2026-10-07 20:25


NVD link : CVE-2026-102268

Mitre link : CVE-2026-102268

CVE.ORG link : CVE-2026-102268


JSON object : View

Products Affected

pyjwt_project

  • pyjwt
CWE
CWE-347

Improper Verification of Cryptographic Signature