CVE-2026-65603

Description

The Grav Login plugin (grav-plugin-login) versions <= 3.8.11 contain a privilege escalation flaw in the authenticated profile self-update handler (processUserProfile(), the update_user task). Unlike the registration handler, this handler does not strip privilege fields (-groups-,-access-) from user-submitted form data before persisting them. When an administrator has added -groups- and/or -access- to plugins.login.user_registration.fields and the default -regular-/DataUser account backend is in use, a low-privilege authenticated user can POST crafted profile form data (e.g. access[admin][super]=true) to escalate to super-admin, enabling admin panel access, scheduler abuse (RCE), and Twig evaluation. Fixed in 3.8.12.