On June 12 2012 Microsoft announced a vulnerability in the XML Core Services which is part of all current versions of Windows, Office 2003 and Office 2007. This vulnerability could allow a remote attack to execute code on a user's machine if the user visits a specially crafted website using Internet Explorer.
Reason for detection
Websense Advanced Classification Engine contains real time analytics which identifies code that is trying to use this vulnerability to exploit the user's computer.
For more information about this vulnerability, see Microsoft Advisory 2719615.