The Helpdesk Support Ticket System for WooCommerce plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 2.1.6 via the 'id' parameter due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with subscriber-level access and above, to delete arbitrary ticket responses belonging to other users by supplying any stsw_responses row ID to the deletion handler after obtaining the nonce from the admin footer.