ShopEngine < 4.9.5 - Shop Manager+ Privilege Escalation via WXR Import

Description

The plugin is vulnerable to Privilege Escalation, due to the `rum_importer()` function being registered on the WordPress core `import_start` action hook with no plugin-owned capability check and no allowlist filtering, causing arbitrary `<wp_option>` name/value pairs parsed from an attacker-supplied WXR import file to be passed directly to `update_option()`. This makes it possible for authenticated attackers, with Shop Manager-level access and above, to write arbitrary WordPress options - most critically setting `users_can_register` to `1` and `default_role` to `administrator` - enabling open self-registration of Administrator accounts and full site takeover. This is exploitable by Shop Manager-level users because WooCommerce grants that role the `import` capability, allowing it to reach the WordPress Importer flow that fires the `import_start` hook on which `rum_importer()` is registered, contrary to the assumption that the hook is restricted to Administrators.