Testing for exposed session variables
Session variables such as tokens, cookies, or hidden form fields are used by application developers to send data between the client and the server. Since these variables are exposed on the client side, an attacker can manipulate them in an attempt to gain access to unauthorized data or to capture sensitive information.
Burp Suite’s Proxy option provides a feature to enhance the visibility of so-called hidden form fields. This feature allows web application penetration testers to determine the level of sensitivity of the data held in these variables. Likewise, a pentester can determine whether the manipulation of these values produces a different behavior in the application.
Getting ready
Using the OWASP Mutillidae II application and Burp Suite’s Unhide hidden form fields feature under Proxy, we’ll determine whether manipulation of a hidden form field value results in gaining access to unauthorized data.
