fast-jwt: Incomplete patch of CVE-2026-34950: Non-whitespace key-prefix re-enables RSA→HS256 algorithm confusion

fast-jwt: Empty HMAC secret accepted via async key resolver - JWT auth bypass

fast-jwt Affected by Cache Confusion via cacheKeyBuilder Collisions Can Return Claims From a Different Token (Identity/Authorization Mixup)

fast-jwt has an incomplete fix for CVE-2023-48223: JWT Algorithm Confusion via Whitespace-Prefixed RSA Public Key

fast-jwt : Silent claim-validator bypass when JWT payload is a JSON array

fast-jwt accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)

fast-jwt treats raw public JWK JSON as an HMAC secret, enabling HS256 token forgery

fast-jwt: createVerifier accepts unsigned JWTs when key is '' or null and algorithms is explicitly set

ReDoS in fast-jwt when using RegExp in allowed* leading to CPU exhaustion during token verification

Fast-JWT Improperly Validates iss Claims

fast-jwt clockTolerance: Infinity silently bypasses both exp and nbf validation (and persists in the verifier cache)

fast-jwt JWT Algorithm Confusion

fast-jwt: Stateful RegExp (/g or /y) causes non-deterministic allowed-claim validation (logical DoS)

fast-jwt: Verifier cache accepts expired JWTs without iat.