===================================================================== CERT-Renater Note d'Information No. 2009/VULN353 _____________________________________________________________________ DATE : 08/09/2009 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : Windows 2000, Windows Server 2003, Windows Vista, Windows Server 2008. ====================================================================== KB967723 http://www.microsoft.com/technet/security/Bulletin/MS09-048.mspx ______________________________________________________________________ Microsoft Security Bulletin MS09-048 - Critical Vulnerabilities in Windows TCP/IP Could Allow Remote Code Execution (967723) Published: September 08, 2009 Version: 1.0 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, and Important for all supported editions of Microsoft Windows 2000 Service Pack 4 and Windows Server 2003. 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. Affected Software Microsoft Windows 2000 Service Pack 4 Windows Server 2003 Service Pack 2 Windows Server 2003 x64 Edition Service Pack 2 Windows Server 2003 with SP2 for Itanium-based Systems Windows Vista, Windows Vista Service Pack 1, and Windows Vista Service Pack 2 Windows Vista x64 Edition, Windows Vista x64 Edition Service Pack 1, and Windows Vista x64 Edition Service Pack 2 Windows Server 2008 for 32-bit Systems and Windows Server 2008 for 32-bit Systems Service Pack 2 Windows Server 2008 for x64-based Systems and Windows Server 2008 for x64-based Systems Service Pack 2 Windows Server 2008 for Itanium-based Systems and Windows Server 2008 for Itanium-based Systems Service Pack 2 Vulnerability Information TCP/IP Zero Window Size Vulnerability - CVE-2008-4609 A denial of service vulnerability exists in TCP/IP processing in Microsoft Windows due to the way that Windows handles an excessive number of established TCP connections. The effect of this vulnerability can be amplified by the requirement to process specially crafted packets with a TCP receive window size set to a very small value or zero. An attacker could exploit the vulnerability by flooding a system with specially crafted packets causing the affected system to stop responding to new requests or automatically restart. TCP/IP Timestamps Code Execution Vulnerability - CVE-2009-1925 A remote code execution vulnerability exists in the Windows TCP/IP stack due to the TCP/IP stack not cleaning up state information correctly. This causes the TCP/IP stack to reference a field as a function pointer when it actually contains other information. An anonymous attacker could exploit the vulnerability by sending specially crafted TCP/IP packets to a computer that has a service listening over the network. An attacker who successfully exploited this vulnerability could take complete control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. TCP/IP Orphaned Connections Vulnerability - CVE-2009-1926 A denial of service vulnerability exists in TCP/IP processing in Microsoft Windows due to an error in the processing of specially crafted packets with a small or zero TCP receive window size. If an application closes a TCP connection with pending data to be sent and an attacker has set a small or zero TCP receive window size, the affected server will not be able to completely close the TCP connection. An attacker could exploit the vulnerability by flooding a system with specially crafted packets causing the affected system to stop responding to new requests. The system would remain non-responsive even after the attacker stops sending malicious packets. ====================================================================== ========================================================= Les serveurs de référence du CERT-Renater http://www.urec.fr/securite http://www.cru.fr/securite http://www.renater.fr ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 151 bd de l'Hopital | fax : 01-53-94-20-41 + + 75013 Paris | email: certsvp@renater.fr + =========================================================