CVE-2026-39976: Laravel Passport

High severity, CVSS 7.1. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Laravel Passport: from 13.0.0, before 13.7.1 (fixed in 13.7.1)

Published 2026-04-09. Last modified 2026-06-17.