CVE-2026-39976
Laravel Passport's TokenGuard Authenticates Unrelated User for Client Credentials Tokens
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
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.
Timeline
ID reserved
By GitHub_M
- 1 day later
· 1 day later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N |
| NVDNVD · Analyzed | 3.1 | High7.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.29% · top 78% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.1.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Packagistlaravel/passportGHSA-349c-2h2f-mxf6 (opens in a new tab)
References (5)
- https://github.com/laravel/passport/security/advisories/GHSA-349c-2h2f-mxf6 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/laravel/passport/issues/1900 (opens in a new tab)x_refsource_MISC
- https://github.com/thephpleague/oauth2-server/issues/1456#issuecomment-2734989996 (opens in a new tab)x_refsource_MISC
- https://github.com/laravel/passport/pull/1901 (opens in a new tab)x_refsource_MISC
- https://github.com/laravel/passport/pull/1902 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-349c-2h2f-mxf6 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-39976)Record last updated .