{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-35042", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-03-31T21:06:06.428Z", "datePublished": "2026-04-06T17:02:12.180Z", "dateUpdated": "2026-04-06T17:02:12.180Z"}, "containers": {"cna": {"title": "fast-jwt accepts unknown `crit` header extensions (RFC 7515 \u00a74.1.11 MUST violation)", "problemTypes": [{"descriptions": [{"cweId": "CWE-345", "lang": "en", "description": "CWE-345: Insufficient Verification of Data Authenticity", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-636", "lang": "en", "description": "CWE-636: Not Failing Securely ('Failing Open')", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-hm7r-c7qw-ghp6", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-hm7r-c7qw-ghp6"}, {"name": "https://www.rfc-editor.org/rfc/rfc7515.html#section-4.1.11", "tags": ["x_refsource_MISC"], "url": "https://www.rfc-editor.org/rfc/rfc7515.html#section-4.1.11"}], "affected": [{"vendor": "nearform", "product": "fast-jwt", "versions": [{"version": "<= 6.1.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-04-06T17:02:12.180Z"}, "descriptions": [{"lang": "en", "value": "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 \u00a74.1.11. 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."}], "source": {"advisory": "GHSA-hm7r-c7qw-ghp6", "discovery": "UNKNOWN"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "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 \u00a74.1.11. 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."}], "id": "CVE-2026-35042", "lastModified": "2026-04-06T17:17:13.410", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-04-06T17:17:13.410", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-hm7r-c7qw-ghp6"}, {"source": "security-advisories@github.com", "url": "https://www.rfc-editor.org/rfc/rfc7515.html#section-4.1.11"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-345"}, {"lang": "en", "value": "CWE-636"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{}