CVE-2026-102273PyJWT accepts public JWK containers as HMAC secrets

Descripción

PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, PyJWT HMACAlgorithm.prepare_key is affected because HMAC key guard only recognizes top-level public JWK forms and misses container representations. This occurs when an application allows HMAC and asymmetric algorithms and passes a public JWK container as the raw key. As a result, public asymmetric key material is accepted as the HMAC secret. Consequently, an attacker who knows the public key can forge a token with arbitrary authenticated claims. This issue is fixed in version 2.14.0.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/jpadilla/pyjwt/security/advisories/GHSA-w2cx-738m-mc7w Vendor Advisory
• https://github.com/jpadilla/pyjwt/commit/801cd128528c62d9b23fcd161d1a2e1c17982f95 Patch
• https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 ProductRelease Notes