MSDN:

internetexplorer9logoThe August 2012 Cumulative Security Update for Internet Explorer is now available via Windows Update. This security update resolves four privately reported vulnerabilities in Internet Explorer. The most severe vulnerabilities could allow remote code execution if a user views a specially crafted Web page using Internet Explorer. An attacker who successfully exploited any of these vulnerabilities could gain the same user rights as the current user. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights This security update is rated Critical for Internet Explorer 6, Internet Explorer 7, Internet Explorer 8, and Internet Explorer 9 on Windows clients and Moderate for Internet Explorer 6, Internet Explorer 7, Internet Explorer 8, and Internet Explorer 9 on Windows servers For more information, see the full bulletin.

Most customers have enabled automatic updating and do not need to take any action. We recommend that customers, who have not enabled automatic updating, enable it (Start Menu, type “Windows Update”). We recommend that administrators, enterprise installations, and end users who want to install this security update manually, apply the update immediately using update management software or by checking for updates using the Microsoft Update service.

—Tyson Storey, Program Manager, Internet Explorer