Proventia Network IPS, Proventia Desktop, RealSecure Network, RealSecure Server Sensor, Proventia Network MFS, Proventia-G 1.1 and earlier, Proventia Network IDS, IBM Security Server Protection for Windows, Virtual Server Protection for Vmware, Proventia Server IPS for Linux technology:
This signature detects TCP Selective-ACK packets that are malformed in a very specific manner so as disrupt the Windows operating system and cause a denial of service.
Proventia Network IPS, Proventia Desktop, RealSecure Network, RealSecure Server Sensor, Proventia Network MFS, Proventia-G 1.1 and earlier, Proventia Network IDS, IBM Security Server Protection for Windows, Virtual Server Protection for Vmware, Proventia Server IPS for Linux technology: It is possible for a Selective-ACK with a badly out of sequence SACK block to trigger this signature without causing the DoS exploit.
Medium
Proventia Network IPS: XPU 30.020, Proventia Desktop: 2480, RealSecure Network: XPU 30.020, RealSecure Server Sensor: XPU 30.020, Proventia Network MFS: XPU 30.020, Proventia-G 1.1 and earlier: XPU 30.020, Proventia Network IDS: XPU 30.020, IBM Security Server Protection for Windows: 2.1.14.2480, IBM Security Server Protection for Windows: 2.0.300.2480, Virtual Server Protection for Vmware: XPU 30.020, Proventia Server IPS for Linux technology: 30.020
Microsoft Windows Vista, Microsoft Windows Vista: x64, Microsoft Windows Vista: SP1, Microsoft Windows Vista: SP1 x64, Microsoft Windows Server 2008: Itanium, Microsoft Windows Server 2008: x32, Microsoft Windows Server 2008: x64, Microsoft Windows Vista: SP2 x64, Microsoft Windows Vista: SP2, Microsoft Windows Server 2008: SP2 x32, Microsoft Windows Server 2008: SP2 x64, Microsoft Windows Server 2008: SP2 Itanium
Denial of Service
Microsoft Windows is vulnerable to a denial of service, caused by an error in the TCP/IP stack when processing TCP packets containing a malicious selective acknowledgment (SACK) value. By sending a series of specially-crafted TCP packets with a malformed selective acknowledgment (SACK) value, a remote attacker could exploit this vulnerability to cause the system to become unresponsive.
Apply the appropriate patch for your system, as listed in Microsoft Security Bulletin MS10-009. See References.
Microsoft Security Bulletin MS10-009
Vulnerabilities in Windows TCP/IP Could Allow Remote Code Execution (974145)
http://www.microsoft.com/technet/security/bulletin/ms10-009.mspx
ISS X-Force
Microsoft Windows TCP/IP SACK denial of service
http://www.iss.net/security_center/static/55897.php
CVE
CVE-2010-0242
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2010-0242