The plugin does not sanitise and escape the woocs_in_order_currency parameter of the woocs_get_products_price_html AJAX action (available to both unauthenticated and authenticated users) before outputting it back in the response, leading to a Reflected Cross-Site Scripting
https://example.com/wp-admin/admin-ajax.php?action=woocs_get_products_price_html&woocs_in_order_currency=<img src onerror=alert(`XSS`)>