CVE-2026-107723
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
fast-jwt : Silent claim-validator bypass when JWT payload is a JSON array
fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.0, fast-jwt createVerifier accepts a validly signed JWT whose payload is a JSON array because src/decoder.js checks that the payload is an object but does not reject arrays. The claim validator loop then finds no named exp, nbf, iss, aud, sub, jti, or nonce properties and silently skips those configured checks, returning the array as a successfully verified payload. An attacker who can produce or influence a validly signed token may bypass expiry, issuer, audience, subject, revocation, and replay protections. The opt-in requiredClaims option can block missing claims, and signature verification itself is not bypassed. This issue is fixed in version 6.3.0.
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
fast-jwt
- Vendor
- nearform
- Product
- fast-jwt
- Platforms
- Unknown
- Default status
Unknown
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| < 6.3.0 | affected | Unavailable | Unavailable | Unavailable | None listed |