Microsoft Help and Support Center Remote Code Execution Vulnerability (2229593)

Summary
This host is missing a critical security update according to Microsoft Bulletin MS10-042.
Impact
Successful exploitation could allow remote attackers to inject malicious code in the Help and Support Center and execute arbitrary commands on a vulnerable system by tricking a user into visiting a specially crafted web page. Impact Level: System
Solution
Run Windows Update and update the listed hotfixes or download and update mentioned hotfixes in the advisory from the below link, http://www.microsoft.com/technet/security/Bulletin/MS10-042.mspx
Insight
The flaw is due to the error in 'MPC::HTML::UrlUnescapeW()' function within the Help and Support Center application (helpctr.exe) that does not properly check the return code of 'MPC::HexToNum()' when escaping URLs.
Affected
Microsoft Windows XP Service Pack 3 and prior. Microsoft Windows 2003 Service Pack 2 and prior.
References