The Grav admin plugin prior to version 1.10.11 does not correctly verify caller's privileges. As a consequence, users with the permission `admin.login` can install third-party plugins and their dependencies. By installing the right plugin, an attacker can obtain an arbitrary code execution primitive and elevate their privileges on the instance. The vulnerability has been addressed in version 1.10.11. As a mitigation blocking access to the `/admin` path from untrusted sources will reduce the probability of exploitation.
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.