{"id":"CVE-2026-39976","summary":"Laravel Passport's TokenGuard Authenticates Unrelated User for Client Credentials Tokens","details":"Laravel Passport provides OAuth2 server support to Laravel. From 13.0.0 to before 13.7.1, there is an Authentication Bypass for client_credentials tokens. the league/oauth2-server library sets the JWT sub claim to the client identifier (since there's no user). The token guard then passes this value to retrieveById() without validating it's actually a user identifier, potentially resolving an unrelated real user. Any machine-to-machine token can inadvertently authenticate as an actual user. This vulnerability is fixed in 13.7.1.","aliases":["GHSA-349c-2h2f-mxf6"],"modified":"2026-07-08T08:05:08.910131327Z","published":"2026-04-09T16:50:42.326Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39976.json","cwe_ids":["CWE-287"],"cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39976.json"},{"type":"ADVISORY","url":"https://github.com/laravel/passport/security/advisories/GHSA-349c-2h2f-mxf6"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-39976"},{"type":"REPORT","url":"https://github.com/laravel/passport/issues/1900"},{"type":"REPORT","url":"https://github.com/thephpleague/oauth2-server/issues/1456#issuecomment-2734989996"},{"type":"FIX","url":"https://github.com/laravel/passport/pull/1901"},{"type":"FIX","url":"https://github.com/laravel/passport/pull/1902"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/laravel/passport","events":[{"introduced":"1d89db335f9b6628f5ebeca8b64e3f7cbd89ec8b"},{"fixed":"ca14d978801d328dc5b425af37781db9fcbace8c"}],"database_specific":{"extracted_events":[{"introduced":"13.0.0"},{"fixed":"13.7.1"}],"source":["AFFECTED_FIELD","CPE_RANGE"],"cpe":"cpe:2.3:a:laravel:passport:*:*:*:*:*:laravel:*:*"}}],"versions":["v13.7.0","v13.6.0","v13.5.0","v13.4.4","v13.4.3","v13.4.2","v13.4.1","v13.4.0","v13.3.0","v13.2.2","v13.2.1","v13.2.0","v13.1.0","v13.0.6","v13.0.5","v13.0.4","v13.0.3","v13.0.2","v13.0.1","v13.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-39976.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N"}]}