WP Maps Pro <= 6.1.0 - Unauthenticated Privilege Escalation via Administrator Account Creation to wpgmp_temp_access_ajax AJAX Action

The WP Maps Pro plugin for WordPress is vulnerable to Privilege Escalation via Administrator Account Creation in all versions up to, and including, 6.1.0. This is due to the wpgmp_temp_access_ajax AJAX action being registered with wp_ajax_nopriv_ and protected only by a nonce check using the fc-call-nonce nonce, which is publicly embedded into every frontend page via wp_localize_script as the nonce field of the wpgmp_local JavaScript object, rendering the check ineffective as an access control mechanism. This makes it possible for unauthenticated attackers to invoke the wpgmp_temp_access_support handler with check_temp=false, which unconditionally creates a new WordPress user with the hardcoded role of administrator via wp_insert_user() and returns a magic login URL that, when visited, calls wp_set_auth_cookie() to fully authenticate the attacker as the newly created administrator, resulting in complete site takeover.