Divi Form Builder <= 5.1.8 - Authenticated (Subscriber+) Missing Authorization to Privilege Escalation via User Profile Update Form

The Divi Form Builder plugin for WordPress is vulnerable to Missing Authorization in versions up to, and including, 5.1.8. This is due to the update_user() function accepting a user ID parameter from form submissions without verifying that the authenticated user has permission to edit that specific user account, and the handle_register_submission() function only checking if any user is logged in rather than validating permissions for the target user. This makes it possible for authenticated attackers, with subscriber-level access and above, to change the email address and password of any user account, including administrators, resulting in complete account takeover.