Improper Verification of Cryptographic Signature Affecting py3.11-pyjwt package, versions <2.14.0-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.19% (8th percentile)

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  • Snyk IDSNYK-MINIMOSLATEST-PY311PYJWT-20343435
  • published1 Oct 2026
  • disclosed28 Sept 2026

Introduced: 28 Sep 2026

NewCVE-2026-102272  (opens in a new tab)
CWE-347  (opens in a new tab)

How to fix?

Upgrade Minimos:latest py3.11-pyjwt to version 2.14.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream py3.11-pyjwt package and not the py3.11-pyjwt package as distributed by Minimos. See How to fix? for Minimos:latest relevant fixed versions and status.

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 Base Scores

version 3.1