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 xc_woo_printer_preview 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.
https://codecanyon.net/item/woocommerce-google-cloud-print/21129093