CVE-2026-35042: falha de alta gravidade em nearform fast-jwt
fast-jwt accepts unknown `crit` header extensions (RFC 7515 §4.1.11 MUST violation)
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21Vexday Risk Score
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ssvc Trackcvss 7.5epss 0.2%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
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