{"id":"CVE-2026-107724","revision":"27e998aed097451cb0aabeffcbb4ee0d","records":[{"revision":"27e998aed097451cb0aabeffcbb4ee0d","observedAt":"2026-10-25T05:17:13.11+00:00","statement":{"source":"nvd","id":"CVE-2026-107724","aliases":[],"title":"fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.2.4, fast-jwt can classify raw serialized public JWK or JWKS JSON as an HMAC secret because src/crypto.js performDetectPublicKeyAlgorithms treats non-PEM strings as symmetric …","description":"fast-jwt provides fast JSON Web Token (JWT) implementation. In 6.2.4, fast-jwt can classify raw serialized public JWK or JWKS JSON as an HMAC secret because src/crypto.js performDetectPublicKeyAlgorithms treats non-PEM strings as symmetric key material. If HS256 is explicitly allowed or inferred, an attacker who knows the exact serialized public-key bytes can use those bytes as an HMAC key and create a token containing arbitrary claims that createVerifier accepts. Serialization ordering or whitespace differences can prevent exploitation, and applications using supported PEM keys with an asymmetric-only algorithm allowlist are not affected. This issue is fixed in version 6.3.0.","state":0,"publishedAt":"2026-10-08T22:17:28.8+00:00","modifiedAt":"2026-10-09T16:17:23.74+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","score":7.4,"severity":"HIGH"}],"references":["https://github.com/nearform/fast-jwt/commit/10f9591349199ed2ab9fa1748ce92cdca697f6cf","https://github.com/nearform/fast-jwt/pull/636","https://github.com/nearform/fast-jwt/releases/tag/v6.3.0","https://github.com/nearform/fast-jwt/security/advisories/GHSA-g3jj-5cmm-3hxx"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-107724","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Deferred","weaknesses":["CWE-347"],"productCriteria":[],"sourceDates":{"published":"2026-10-08T22:17:28.800","lastModified":"2026-10-09T16:17:23.740"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-107724","identifiers":["CVE-2026-107724"]},"retained":false,"historicalAffected":[]}],"coverage":[]}