9.1

CVE-2026-102266

Exploit

PyJWK accepts empty HMAC keys, bypassing PyJWT's empty-key validation

PyJWT is a Python implementation of JSON Web Token standards. From 2.13.0 until 2.14.0, HMACAlgorithm.from_jwk is affected because PyJWK verification path used the decoded key without applying prepare_key validation. This occurs when a trusted JWK Set contains an oct entry with an empty k value. As a result, an attacker signs an HMAC token with the same zero-length key accepted by PyJWT. Consequently, forged token can carry arbitrary authenticated claims. This issue is fixed in version 2.14.0.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Pyjwt Project ≫ Pyjwt Version 2.13.0
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.18% 0.062
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 9.1 3.9 5.2
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
security-advisories@github.com 7.4 2.2 5.2
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CWE-347 Improper Verification of Cryptographic Signature

The product does not verify, or incorrectly verifies, the cryptographic signature for data.

https://github.com/jpadilla/pyjwt/releases/tag/2.14.0
Product
Release Notes
https://github.com/jpadilla/pyjwt/commit/f91ed44dd65baaf457f4b3353ed35e98a753934c
Patch
https://github.com/jpadilla/pyjwt/security/advisories/GHSA-9j54-fg26-wv3r
Vendor Advisory
Exploit