The WPMasterToolKit plugin for WordPress is vulnerable to PHP Code Injection in all versions up to, and including, 2.13.0. This is due to the plugin allowing Author-level users to create and execute arbitrary PHP code through the Code Snippets feature without proper capability checks. This makes it possible for authenticated attackers, with Contributor-level access and above, to execute arbitrary PHP code on the server, leading to remote code execution, privilege escalation, and complete site compromise.