CVE-2026-39976

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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/laravel/passport/issues/1900	Exploit Issue Tracking
https://github.com/laravel/passport/pull/1901	Issue Tracking Patch
https://github.com/laravel/passport/pull/1902	Issue Tracking Patch
https://github.com/laravel/passport/security/advisories/GHSA-349c-2h2f-mxf6	Mitigation Vendor Advisory
https://github.com/thephpleague/oauth2-server/issues/1456#issuecomment-2734989996	Issue Tracking Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:laravel:passport:*:*:*:*:*:laravel:*:*

History

No history.

Information

Published : 2026-04-09 17:16

Updated : 2026-06-17 10:42

NVD link : CVE-2026-39976

Mitre link : CVE-2026-39976

CVE.ORG link : CVE-2026-39976

JSON object : View

Products Affected

laravel

passport

CWE

CWE-287

Improper Authentication

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