This Security Update resolves a vulnerability that could allow remote code execution in Microsoft Ofice Publisher 2007. It can be downloaded directly from the Windows Update site, specifically under Office section or using automatic updates in Windows. It´s supported by Windows 2000 with SP1, Windows XP, Windows Vista and Windows 2003 Server and for it´s installation requires Microsoft Windows Installer 3.1. The vulnerability appears because of the way that Micrfosoft Office Publisher 2007 deals with .pub files so this security update changes this matter. For more detailed information you can check the Description of the Security Update for Microsoft Office Publisher 2007 number KB936646 in Microsoft´s site.