LearnPress <= 4.4.4 - Missing Authorization to Authenticated (Editor+) Limited Option Update via 'field_name' Parameter

The LearnPress plugin for WordPress is vulnerable to unauthorized modification of arbitrary WordPress options in versions up to, and including, 4.4.4 via the learnpress_create_page AJAX action. The LP_Admin_Ajax::create_page() handler only checks the edit_pages capability and a wp_rest nonce (both available to Editors), then reads the field_name parameter from the request without restricting it to a learn_press_* allow-list before passing it as the option key to LP_Helper::create_page(), which calls update_option($key_option, $page_id). This makes it possible for authenticated attackers, with Editor-level access and above, to update arbitrary WordPress options to a positive integer (a newly created page ID), enabling actions such as flipping users_can_register to a truthy value to open public registration, corrupting active_plugins to break the site, or otherwise tampering with site-wide settings normally reserved for administrators.