CVE-2026-102272
highPyJWT is a Python implementation of JSON Web Token standards.
Vendor / product: Pyjwt Project — pyjwt
PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, HMACAlgorithm.prepare_key in jwt/algorithms.py is affected because raw-JWK detector does not normalize accepted Unicode byte-order marks before checking for JSON. This occurs when a public JWK is prefixed with a UTF-8 BOM and used in a mixed-algorithm verification path. As a result, public JWK bypasses asymmetric-key detection and becomes the HMAC secret. Consequently, an attacker who knows the public key can forge authenticated tokens. This issue is fixed in version 2.14.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://github.com/jpadilla/pyjwt/commit/180783930de91876bc0d601f826a1f2956057291 security-advisories@github.com
- https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 security-advisories@github.com
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-r6x4-923q-g947 security-advisories@github.com
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-r6x4-923q-g947 134c704f-9b21-4f2e-91b3-4a467353bcc0