Microsoft just released its May 2011 security update: Two bulletins covering three vulnerabilities. Microsoft also announced that it will be modifying its Exploitability Index, a patch rating system. The new rating more accurately reflects risk to customers that keep their environments updated with latest product releases. Users of the new Office 2010 for both Windows and Mac OS X are not affected by the vulnerability. The latest version, which is Office 2010, was not affected, therefore the exploitability rating for the latest version was ‘Not Affected'”]
Source: https://www.csoonline.com/article/2134703/microsoft-s-may-2011-security-update.html