Solace Extra <= 1.6.0 - Missing Authorization to Unauthenticated Site Content Deletion and Unauthorized Demo Import via action-import-zip AJAX Action

The Solace Extra plugin for WordPress is vulnerable to unauthorized modification and loss of data due to a missing capability check on the import_zip() function in versions up to, and including, 1.6.0. The handler is registered on both wp_ajax_action-import-zip and wp_ajax_nopriv_action-import-zip and only verifies the 'ajax-nonce' nonce, which is emitted on every admin page via wp_localize_script (unrestricted admin_enqueue_scripts hook) and is therefore accessible to any authenticated user including Subscribers. This makes it possible for authenticated attackers, with Subscriber-level access and above, to wipe navigation menus, sidebar widgets (via update_option('sidebars_widgets', array())), all theme mods (via remove_theme_mods()), and Elementor templates, as well as trigger arbitrary demo-content imports.