Microsoft Windows contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on an affected system. Updates are available.
Microsoft Windows Vista SP2 and prior and Windows Server 2008 SP2 and prior contain a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code on an affected system.
This vulnerability exists due to errors when handling input contained within TCP/IP packets. An unauthenticated, remote attacker could exploit this vulnerability by sending a malicious network packet to the vulnerable system. If the exploit is successful, the attacker could execute code resulting in a complete system compromise.
Microsoft has confirmed this vulnerability in a security bulletin and released software updates that correct it.
Systems running the following versions of Microsoft Windows are vulnerable:
Windows Vista SP2 and prior
Windows Vista x64 Edition SP2 and prior
Windows Server 2008 for 32-bit Systems SP2 and prior
Windows Server 2008 for x64-based Systems SP2 and prior
Windows Server 2008 for Itanium-based Systems SP2 and prior
Attackers only need to send malicious TCP/IP packets to a vulnerable system in order to accomplish an exploit, which would render all Internet-facing servers potentially vulnerable to external exploitation. Because technical details have not yet been released publicly, the development of exploits may be delayed. Administrators are advised to apply available patches immediately.
The update available from Microsoft corrects this vulnerability by changing the way Windows processes TCP/IP packets.
Microsoft has released a security bulletin at the following link: MS09-048
An unauthenticated, remote attacker could exploit this vulnerability to execute arbitrary code with elevated privileges, possibly resulting in a complete system compromise.
This vulnerability exists due to errors in handling input contained within TCP/IP packets. Windows may treat data as a function pointer when a field contains other data that is potentially supplied by the user. An unauthenticated, remote attacker could exploit this vulnerability by sending malicious TCP/IP packets to the affected system. The processing of data contained within the network packets could cause memory corruption that the attacker could leverage to execute arbitrary code.
Administrators are advised to apply the available software updates.
Administrators are advised to restrict network access to affected systems.
Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
Administrators are advised to monitor critical systems.
Microsoft customers can obtain updates directly by using the links in the security bulletin. These updates are also distributed by Windows automatic update features and available on the Windows Update website. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.
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