The Kali Forms plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 2.4.9 via the 'form_process' function. This is due to the 'prepare_post_data' function mapping user-supplied keys directly into internal placeholder storage, combined with the use of 'call_user_func' on these placeholder values. This makes it possible for unauthenticated attackers to execute code on the server.