NuytsTech Security

CVE-2026-35042

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fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.1.0 and earlier, fast-jwt does not validate the crit (Critical) Header Parameter defined in RFC 7515 §4.1.11. When a JWS token contains a crit array listing extensions that fast-jwt does not understand, the library accepts the token instead of rejecting it. This violates the MUST requirement in the RFC.

More information : https://github.com/nearform/fast-jwt/security/advisories/GHSA-hm7r-c7qw-ghp6

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