The Database Backup for WordPress plugin for WordPress is vulnerable to unauthorized arbitrary file read and deletion in all versions up to, and including, 2.5.2. This is due to the plugin not properly enforcing the return value of its authorization check combined with a user-controlled backup directory parameter. This makes it possible for unauthenticated attackers to read and delete arbitrary files on the server, leading to Sensitive Information Exposure and potential site takeover. Note: This vulnerability is only exploitable in WordPress Multisite environments where the deprecated is_site_admin() function exists.