Lack of authentication or validation in motor_load_more, motor_gallery_load_more, motor_quick_view and motor_project_quick_view AJAX handlers of the Motor WordPress theme before 3.1.0 allows an unauthenticated attacker access to arbitrary files in the server file system, and to execute arbitrary php scripts found on the server file system. We found no vulnerability for uploading files with this theme, so any scripts to be executed must already be on the server file system.