CVE-2026-107720
CVE-2026-107720 · fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set
Esta página presenta datos de fuentes públicas de vulnerabilidades. Consulta el aviso original antes de actualizar.
fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.1, fast-jwt createVerifier accepts an unsigned JWT when key is an empty string or null and algorithms is a non-empty allowlist. Falsy synchronous keys bypass prepareKeyOrSecret, allowedAlgorithms remains active, hasKey is false, and the empty signature avoids the verifySignature gate. An attacker can therefore submit a token containing arbitrary claims without possessing a signing key, resulting in authentication or authorization bypass. Claim validators still run, and non-empty keys, an empty key without algorithms, and the async key resolver path do not have this behavior. This issue is fixed in version 6.3.1.
CVSS 7.4 · Alta · EPSS 0,3% · Corrección disponible
- Publicación
- Actualización
Pila tecnológica: node
Productos y versiones afectados
Fuentes originales
- https://github.com/nearform/fast-jwt/security/advisories/GHSA-8wpc-h4q6-8fxv
- https://github.com/nearform/fast-jwt/pull/649
- https://github.com/nearform/fast-jwt/commit/e22a151e83bf6d5e54e281216982d204d5665534
- https://github.com/nearform/fast-jwt/releases/tag/v6.3.1
- https://nvd.nist.gov/vuln/detail/CVE-2026-107720