An XSS vulnerability occurs due to insufficient client-side validation on web pages if the web pages load the data from users and include this in web pages without validating the data. This lets the hacker’s script execute on a victim's browser and show arbitrary content, that the victim believes is real and from the application, and so he provides his information. This means that XSS attacks potentially harm the users of the application (victims) but not the application itself. The following diagram represents the flow of a Cross-Site Scripting (XSS) attack:
XSS vulnerability attacks are powerful, as they execute ...
