Countering Cross-Site Scripting in Web-based Applications

Today's dynamic web-based applications have become a normal and critical asset to an organizations business. They come with an increase in the number of web vulnerabilities and attacks. These weaknesses allow hackers to focus their attention on attacking this important information source. The most common vulnerability is cross-site scripting (XSS) and one of the Open Web Application Security project (OWASP) top ten web-threats. XSS occurs when a Web-based application allows untrusted information be accepted and sent back to a browser. Also they can execute scripts within a browser that can deface web sites, redirect users to malicious content and hijack browsers. One reason for this problem was the lack of developers understanding the causes of XSS. In this paper, the authors address the causes of XSS and countermeasures to defense against these threats.