high7.4
CVE-2026-102272
PyJWT is a Python implementation of JSON Web Token standards.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | PyJWT | = 2.13.0 | 2.14.0 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Pyjwt Project | Pyjwt | Version 2.13.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-r6x4-923q-g947
- https://github.com/jpadilla/pyjwt/security/advisories/GHSA-r6x4-923q-g947
- https://nvd.nist.gov/vuln/detail/CVE-2026-102272
- https://github.com/jpadilla/pyjwt/commit/180783930de91876bc0d601f826a1f2956057291
- https://github.com/jpadilla/pyjwt/releases/tag/2.14.0