Wholesale Market <= 2.2.2 - Authenticated (Subscriber+) Privilege Escalation via 'role_required' Parameter

The Wholesale Market plugin for WordPress is vulnerable to privilege escalation in versions up to, and including, 2.2.2 via the ced_wholesale_request_send AJAX action. The ced_wholesale_request_send_callback() handler only verifies a nonce (which is exposed to any authenticated user through wp_localize_script on the frontend) and that the caller has a positive user ID, then calls WP_User::add_role() with the client-supplied role_required POST parameter without restricting the value to an allowlist of wholesale roles. This makes it possible for authenticated attackers, with Subscriber-level access and above, to elevate their privileges to Administrator when the site administrator has enabled the 'Assigning requested role directly' option.