CVE-2026-107719: fallo de gravedad media en nearform fast-jwt
fast-jwt: Verifier cache accepts expired JWTs without iat.
Publicada el · Actualizada el
Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.
13Vexday Risk Score
Sin señal de explotación. Ningún artefacto público de explotación conocido hasta ahora.
ssvc Trackcvss 4.2epss 0.3%
fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.4, the fast-jwt createVerifier cache can continue accepting a previously valid, signed JWT after its exp time when caching is enabled and the token has exp but no iat. In src/verifier.js, cacheSet derives the exp cache deadline only when iat is present, so the cache falls back to cacheTTL, and a later cache hit returns the saved payload before verifyToken rechecks expiration. An attacker who can replay the same cached bearer token can extend access until the cache entry expires, but cannot forge a token through this issue. This issue is fixed in version 6.3.4.
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
Productos afectados
nearform · fast-jwtCVEs relacionadas — nearform fast-jwt
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