This security update resolves five privately reported vulnerabilities in Microsoft Windows. The more severe of these vulnerabilities could allow elevation of privilege if an attacker logs on to a system and runs a specially crafted application. An attacker must have valid logon credentials and be able to log on locally to exploit this vulnerability.
This security update is rated Important for all supported releases of Windows XP, Windows Server 2003, Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, and Windows RT, and Moderate for Windows 8.1, Windows Server 2012 R2, and Windows RT 8.1. For more information, see the subsection, Affected and Non-Affected Software, in this section.
The security update addresses the vulnerabilities by correcting the way that the Windows kernel-mode driver validates memory address values by helping to ensure that the Windows kernel-mode driver properly handles objects in memory, by ensuring that the Windows kernel-mode drivers properly validate array indexes when loading TrueType font files, and by correcting the way that the Windows audio port-class driver handles objects in memory. For more information about the vulnerabilities, see the Frequently Asked Questions (FAQ) subsection for the specific vulnerability entry under the next section, Vulnerability Information.
Recommendation. Most customers have automatic updating enabled and will not need to take any action because this security update will be downloaded and installed automatically. Customers who have not enabled automatic updating need to check for updates and install this update manually. For information about specific configuration options in automatic updating, see Microsoft Knowledge Base Article 294871.
For administrators and enterprise installations, or end users who want to install this security update manually, Microsoft recommends that customers apply the update at the earliest opportunity using update management software, or by checking for updates using the Microsoft Update service.