The PayPlus Payment Gateway WordPress plugin before 8.2.2 does not perform authorization or order-ownership validation in one of its AJAX actions available to unauthenticated users, allowing them to tamper with the payment-related metadata of arbitrary WooCommerce orders.
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Access control involves the use of several protection mechanisms such as:
When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses: