CVE-2026-102268: fallo crítico en jpadilla pyjwt
PyJWT: Asymmetric-PEM detection bypass: whitespace/line-ending-mutated public keys skip the HS/asymmetric confusion guard
Publicada el · Actualizada el
48Vexday Risk Score
Sin señal de explotación. Ella tiene prueba de concepto pública.
ssvc Attendcvss 9.1epss 0.2%
de la publicación al arma4 días
Publicada en NVD28 sept
1ª PoC+4d
probabilidad de explotación
0.2%top 92% de las CVE
explotación observada
noninguna fuente lo reporta
1 exploit(s) público(s)
PyJWT is a Python implementation of JSON Web Token standards. Prior to 2.14.0, is_pem_format in jwt/utils.py is affected because is_pem_format does not recognize every PEM representation accepted by the cryptography loader. This occurs when an application mixes HMAC and asymmetric algorithms and supplies a mutated public-key PEM as raw key bytes. As a result, HMACAlgorithm.prepare_key treats the unrecognized asymmetric public key 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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Productos afectados
jpadilla · pyjwtPoCs públicas encontradas — 1
githubgithub.com/covepseng/cve-2026-102268-poc★ 0⚠ Recursos públicos, para evaluar la exposición de sistemas que controlas o estás autorizado a probar. Prueba solo con autorización.
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