Why does Acunetix highlight parts of the HTTP response in a vulnerability?

Most vulnerabilities are detected by sending a special request (payload) to the server and analyzing the response received from the web application. Starting from Acunetix v13, the part of the HTTP response used to identify the vulnerability is highlighted. You can use the highlighted part of the HTTP response together with the attack details and the HTTP request to manually confirm the existence of the vulnerability.

Let’s take the following Cross-site Scripting vulnerability as an example. The vulnerability has been detected on the page http://testphp.vulnweb.com/comment.php, for name. The POST input name was set to <your name here>'"()&%<acx><ScRiPt >uGLD(9565)</ScRiPt>. The HTTP Request shows how the payload was used.

example cross-site scripting

The vulnerability was detected by checking for the reflection of the payload in the HTTP response and Acunetix highlights the part of the response that caused the vulnerability alert.

example cross-site scripting

This proves the existence of the vulnerability and shows you what to look out for if you decide to perform additional tests to verify the vulnerability.