source: http://www.securityfocus.com/bid/14635/info

PostNuke is prone to multiple cross-site scripting vulnerabilities. These issues are due to a failure of the application to properly sanitize user-supplied input.

This can lead to theft of cookie-based authentication credentials, as well as other types of attacks. 

http://www.example.com/[DIR]/index.php?module=Comments&req=moderate&moderate=<center><h1>xss