CVE-2026-48524: fallo de gravedad baja en jpadilla pyjwt
PyJWT: PyJWKClient unbounded JWKS endpoint requests via attacker-controlled kid values (DoS)
Publicada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
8Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 3.7epss 0.4%
PyJWT is a JSON Web Token implementation in Python. Prior to 2.13.0, PyJWKClient.get_signing_key() forces a fresh HTTP request to the JWKS endpoint for every JWT with an unknown kid value, with no rate limiting. Since kid comes from the unverified token header, an attacker can trigger unlimited outbound requests. The vulnerability surfaces only when a JWKS fetch fails; an attacker can attempt to provoke that with sustained unknown-kid traffic, but the outcome depends on upstream JWKS-endpoint behavior (rate limiting, transient errors) which is beyond the attacker's control. This vulnerability is fixed in 2.13.0.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Productos afectados
jpadilla · pyjwtCVEs relacionadas — jpadilla pyjwt
En el mismo producto, de las más peligrosas a las menos.
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