Without much going into complexity of technical details, one must be attentive of the various cases which have shown that XSS can have serious consequences when inserted on a vulnerable web application. Lot site owners think no more of XSS on the web pages that it cannot be used to steal sensitive data from a database.

This is a frequent mistake made by site owners because the consequences of XSS against a web application and its customers were proven to be very serious. It affects both of application functionality and business operation. An online business web site cannot afford to lose customers simply their web application is vulnerable to XSS intrusions.