CVE-2026-102271PyJWT: Public keys in DER form are accepted as HMAC secrets, bypassing the CVE-2022-29217 guard

Beschreibung

PyJWT is a Python implementation of JSON Web Token standards. From 2.4.0 until 2.14.0, PyJWT HMACAlgorithm.prepare_key is affected because asymmetric-key guard relies on textual markers that are absent from DER encoding. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a DER public key as the shared verification key. As a result, PyJWT uses public DER bytes 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.

Daten: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Wiedergegeben wie in der Quelle, auf Englisch.

Betroffene Produkte und Versionen

Referenzen und Patches

• https://github.com/jpadilla/pyjwt/security/advisories/GHSA-p4g4-x82p-q773 ExploitPatchVendor Advisory
• https://github.com/jpadilla/pyjwt/commit/2798504fa2663364573cf2d1043d8d7fef389499 Patch
• https://github.com/jpadilla/pyjwt/releases/tag/2.14.0 ProductRelease Notes