Vulnerabilities in Windows TCP/IP Could Allow Remote Code Execution (967723)
Published: September 08, 2009 | Updated: September 09, 2009

Version: 2.0
General Information
Executive Summary

This security update resolves several privately reported vulnerabilities in Transmission Control Protocol/Internet Protocol (TCP/IP) processing. The vulnerabilities could allow remote code execution if an attacker sent specially crafted TCP/IP packets over the network to a computer with a listening service. Firewall best practices and standard default firewall configurations can help protect networks from attacks that originate outside the enterprise perimeter. Best practices recommend that systems that are connected to the Internet have a minimal number of ports exposed.

This security update is rated Critical for all supported editions of Windows Vista and Windows Server 2008, Important for all supported editions of Microsoft Windows 2000 and Windows Server 2003, and Low for all supported editions of Windows XP. For more information, see the subsection, Affected and Non-Affected Software, in this section.

The security update addresses the vulnerabilities by dropping existing TCP connections adaptively and limiting the number of new TCP connections until system resources are restored, and changing the manner in which TCP/IP packets are processed. 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. The majority of 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 immediately using update management software, or by checking for updates using the Microsoft Update service.

See also the section, Detection and Deployment Tools and Guidance, later in this bulletin.

Known Issues. Microsoft Knowledge Base Article 967723 documents the currently known issues that customers may experience when installing this security update. The article also documents recommended solutions for these issues.

More information:
http://www.microsoft.com/technet/security/...n/ms09-048.mspx