CVE-2026-107720

{"id": "CVE-2026-107720", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-107720", "role": "CISA Coordinator", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "version": "2.0.3", "timestamp": "2026-10-09T14:31:56.862139Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "security-advisories@github.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.4, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.2, "exploitabilityScore": 2.2}]}, "affected": [{"source": "security-advisories@github.com", "affectedData": [{"vendor": "nearform", "product": "fast-jwt", "versions": [{"status": "affected", "version": "< 6.3.1"}]}]}], "published": "2026-10-08T22:17:28.090", "references": [{"url": "https://github.com/nearform/fast-jwt/commit/e22a151e83bf6d5e54e281216982d204d5665534", "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/pull/649", "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/releases/tag/v6.3.1", "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-8wpc-h4q6-8fxv", "source": "security-advisories@github.com"}, {"url": "https://github.com/nearform/fast-jwt/security/advisories/GHSA-8wpc-h4q6-8fxv", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "security-advisories@github.com", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-347"}]}], "descriptions": [{"lang": "en", "value": "fast-jwt provides fast JSON Web Token (JWT) implementation. Prior to 6.3.1, fast-jwt createVerifier accepts an unsigned JWT when key is an empty string or null and algorithms is a non-empty allowlist. Falsy synchronous keys bypass prepareKeyOrSecret, allowedAlgorithms remains active, hasKey is false, and the empty signature avoids the verifySignature gate. An attacker can therefore submit a token containing arbitrary claims without possessing a signing key, resulting in authentication or authorization bypass. Claim validators still run, and non-empty keys, an empty key without algorithms, and the async key resolver path do not have this behavior. This issue is fixed in version 6.3.1."}], "lastModified": "2026-10-09T15:17:08.947", "sourceIdentifier": "security-advisories@github.com"}