WP Freeio <= 1.2.21 - Unauthenticated Privilege Escalation

The WP Freeio plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 1.2.21. This is due to the process_register() function not restricting what user roles a user can register with. This makes it possible for unauthenticated attackers to supply the 'administrator' role during registration and gain administrator access to the site.