CVE-2026-102272 | BDVDB-2026-380404 Detail

Description#

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.

Impact#

Weaknesses#

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Exploit#

History#

1. Version 12026-09-28Record published in the CVE List.
2. Version 22026-09-29Most recent update recorded in the CVE List.