CVE-2026-35041
Estado: AnalizadaMedia (6.5)—
fast-jwt provides fast JSON Web Token (JWT) implementation. From 5.0.0 to 6.2.0, a denial-of-service condition exists in fast-jwt when the allowedAud verification option is configured using a regular expression. Because the aud claim is attacker-controlled and the library evaluates it against the supplied RegExp, a crafted JWT can trigger catastrophic backtracking in the JavaScript regex engine, resulting in significant CPU consumption during verification. This vulnerability is fixed in 6.2.1.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.43%
- Percentil entre todas las CVEs puntuadas: 35
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-1333
Referencias
- https://github.com/nearform/fast-jwt/commit/b0be0ca161593836a153d5180ca5358ad9b5de94
- https://github.com/nearform/fast-jwt/pull/595
- https://github.com/nearform/fast-jwt/releases/tag/v6.2.1
- https://github.com/nearform/fast-jwt/security/advisories/GHSA-cjw9-ghj4-fwxf
- https://github.com/nearform/fast-jwt/security/advisories/GHSA-cjw9-ghj4-fwxf
JSON original (NVD)
Mostrar
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