phpMyFAQ before 4.1.6 Path Traversal via category image deletion

phpMyFAQ before 4.1.6 fails to validate path traversal sequences in the existing_image field during category updates, allowing authenticated attackers to delete arbitrary files by exploiting insufficient sanitization in Image::delete(). Attackers can delete the database.php configuration file to disable the installation gate and access the public setup wizard to create new superadmin accounts.