The Woocommerce Automatic Order Printing | ( Formerly WooCommerce Google Cloud Print) plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 4.1 via the xcwooprinterpreview AJAX action due to missing validation on a user controlled key. This makes it possible for authenticated attackers, with Subscriber-level access and above, to view other user's invoices and orders which can contain sensitive information.