Optima Express IDX <= 8.7.5 - Unauthenticated Privilege Escalation to 'ihf_clear_cache' AJAX Action to Author Role Assignment

The Optima Express IDX plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 8.7.5. This is due to the `provisionBlogCredentials()` function in `iHomefinderAdmin.php` being reachable via the `wp_ajax_nopriv_ihf_clear_cache` AJAX action — through the call chain `iHomefinderAjaxHandler::clearCache()` → `activateAuthenticationToken()` → `getAuthenticationInfo()` → `provisionBlogCredentials()` — with no capability check, nonce verification, or ownership validation, and the function unconditionally calling `$user->set_role('author')` on whichever WordPress account matches the hard-coded login `optima-express` via `get_user_by('login', 'optima-express')`. This makes it possible for unauthenticated attackers to escalate a pre-registered `optima-express` account to the Author role, gaining `publish_posts`, `upload_files`, and `edit_published_posts` capabilities, including access to the plugin's own `/wp-json/optima-express/v1/blog-post` REST endpoint. Exploitation requires open user registration to be enabled on the target site, and the attacker must register the `optima-express` username before the plugin has had the opportunity to provision that login for its own integration account.