{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-45363", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-05-12T00:51:29.085Z", "datePublished": "2026-07-14T21:32:26.676Z", "dateUpdated": "2026-07-15T13:26:21.205Z" }, "containers": { "cna": { "title": "`jwt` (Ruby gem) - empty-key HMAC bypass", "problemTypes": [ { "descriptions": [ { "cweId": "CWE-287", "lang": "en", "description": "CWE-287: Improper Authentication", "type": "CWE" } ] }, { "descriptions": [ { "cweId": "CWE-326", "lang": "en", "description": "CWE-326: Inadequate Encryption Strength", "type": "CWE" } ] }, { "descriptions": [ { "cweId": "CWE-1391", "lang": "en", "description": "CWE-1391: Use of Weak Credentials", "type": "CWE" } ] } ], "metrics": [ { "cvssV3_1": { "attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 9.1, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "version": "3.1" } } ], "references": [ { "name": "https://github.com/jwt/ruby-jwt/security/advisories/GHSA-c32j-vqhx-rx3x", "tags": [ "x_refsource_CONFIRM" ], "url": "https://github.com/jwt/ruby-jwt/security/advisories/GHSA-c32j-vqhx-rx3x" }, { "name": "https://github.com/jwt/ruby-jwt/commit/9820020869ad147b941e49d96ab8beba35532964", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/jwt/ruby-jwt/commit/9820020869ad147b941e49d96ab8beba35532964" }, { "name": "https://github.com/jwt/ruby-jwt/commit/db560b769a07bd9724e77ff505011ac01872106f", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/jwt/ruby-jwt/commit/db560b769a07bd9724e77ff505011ac01872106f" }, { "name": "https://github.com/jwt/ruby-jwt/releases/tag/v2.10.3", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/jwt/ruby-jwt/releases/tag/v2.10.3" }, { "name": "https://github.com/jwt/ruby-jwt/releases/tag/v3.2.0", "tags": [ "x_refsource_MISC" ], "url": "https://github.com/jwt/ruby-jwt/releases/tag/v3.2.0" } ], "affected": [ { "vendor": "jwt", "product": "ruby-jwt", "versions": [ { "version": "< 2.10.3", "status": "affected" }, { "version": ">= 3.0.0, < 3.2.0", "status": "affected" } ] } ], "providerMetadata": { "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-07-14T21:34:05.174Z" }, "descriptions": [ { "lang": "en", "value": "ruby-jwt is a Ruby implementation of the RFC 7519 OAuth JSON Web Token standard. Prior to 2.10.3 and 3.2.0, JWT.decode(token, '', true, algorithm: 'HS256') accepts an attacker-forged token because OpenSSL::HMAC.digest('SHA256', '', payload) returns a valid digest under an empty key and no empty-key precondition exists in the HMAC algorithm. The same path is reached when a keyfinder block or key_finder: argument returns an empty string, nil, or an array containing nil for an unknown key, affecting HS256, HS384, and HS512 verification through JWT.decode and JWT::EncodedToken#verify_signature!. This issue is fixed in versions 2.10.3 and 3.2.0." } ], "source": { "advisory": "GHSA-c32j-vqhx-rx3x", "discovery": "UNKNOWN" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2026-07-15T13:24:12.081532Z", "id": "CVE-2026-45363", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-07-15T13:26:21.205Z" } } ] } }