source: http://www.securityfocus.com/bid/12626/info

It is reported that Mono is prone to various cross-site scripting attacks. These issues result from insufficient sanitization of user-supplied data and arise when Mono converts Unicode characters ranging from U+ff00-U+ff60 to ASCII.

Mono 1.0.5 is reported vulnerable, however, other versions may be affected as well.

http://www.example.com/attack1.aspx?test=%uff1cscript%uff1ealert('vulnerability')%uff1c/script%uff1e