Shopping cart to payment gateway interactions must be tested by web app penetration testers to ensure the workflow cannot be performed out of sequence. A payment should never be made unless a verification of the cart contents is checked on the server-side first. In the event this check is missing, an attacker can change the price, quantity, or both, prior to the actual purchase.
Testing for the circumvention of work flows
Getting ready
Using the OWASP WebGoat application and Burp, we will exploit a business logic design flaw in which there is no server-side validation prior to a purchase.
