ScanAlert Vulnerability - WebApp Cross Site Scripting

Dear NS Tech Team,

We received a notice from ScanAlert this morning about a new vulnerability, when you test it, it makes our website appear in a iframe window. Here are the details:

<< The remote web application appears to be vulnerable to cross site scripting (XSS).

The cross-site scripting attack is one of the most common, yet overlooked, security problems facing web developers today. A web site is vulnerable if it displays user-submitted content without checking for malicious script tags.

The target of cross-site scripting attacks is not the server itself, but the user files on the server, such as forms and other dynamic content. All a malicious attacker needs to do is find a page that does not properly sanitize user input, but returns the scripting code verbatim to the browser of a visitor to that website. It is important to note that websites that use SSL are just as vulnerable as websites that do not encrypt browser sessions.