CVE-2026-35040

{"id": "CVE-2026-35040", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-35040", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-04-13T20:03:24.317971Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "LOW", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 1.4, "exploitabilityScore": 3.9}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "nearform", "product": "fast-jwt", "versions": [{"status": "affected", "version": "< 6.2.1"}]}]}], "published": "2026-04-09T16:16:27.213", "references": [{"url": "https://github.com/nearform/fast-jwt/commit/18d25904e4617e8753526d1b3ab5a2cccdea726a", "tags": ["Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/pull/593", "tags": ["Issue Tracking", "Patch"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/releases/tag/v6.2.1", "tags": ["Product", "Release Notes"], "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-3j8v-cgw4-2g6q", "tags": ["Exploit", "Mitigation", "Vendor Advisory"], "source": "security-advisories@github.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-440"}, {"lang": "en", "value": "CWE-697"}]}], "descriptions": [{"lang": "en", "value": "fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.2.1, using certain modifiers on RegExp objects in the allowedAud, allowedIss, allowedSub, allowedJti, or allowedNonce options in verify functions can cause certain unintended behaviours. This is because some modifiers are stateful and will cause failures in every second verification attempt regardless of the validity of the token provided. Such modifiers are /g (global matching) and /y (sticky matching). This does NOT allow invalid tokens to be accepted, only for valid tokens to be improperly rejected in some configurations. Instead it causes 50% of valid authentication requests to fail in an alternating pattern. This vulnerability is fixed in 6.2.1."}, {"lang": "es", "value": "fast-jwt proporciona una implementaci\u00f3n r\u00e1pida de JSON Web Token (JWT). Antes de la versi\u00f3n 6.2.1, el uso de ciertos modificadores en objetos RegExp en las opciones allowedAud, allowedIss, allowedSub, allowedJti o allowedNonce en las funciones de verificaci\u00f3n puede causar ciertos comportamientos no deseados. Esto se debe a que algunos modificadores tienen estado y causar\u00e1n fallos en cada segundo intento de verificaci\u00f3n, independientemente de la validez del token proporcionado. Dichos modificadores son /g (coincidencia global) y /y (coincidencia persistente). Esto NO permite que se acepten tokens inv\u00e1lidos, solo que los tokens v\u00e1lidos sean rechazados incorrectamente en algunas configuraciones. En su lugar, causa que el 50% de las solicitudes de autenticaci\u00f3n v\u00e1lidas fallen en un patr\u00f3n alterno. Esta vulnerabilidad est\u00e1 corregida en la versi\u00f3n 6.2.1."}], "lastModified": "2026-10-26T21:10:00.170", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:nearform:fast-jwt:*:*:*:*:*:node.js:*:*", "vulnerable": true, "matchCriteriaId": "2B44A0FB-C037-42E0-9666-7491FF59219D", "versionEndExcluding": "6.2.1"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}