TCP
IP Orphaned Connection Denial of Service Vulnerability
Date Discovered:
09/08/2009
Severity:
High
Operating Systems
Affected:
Microsoft Windows 2000
SP4
Microsoft Windows Server 2003 SP2
Windows Server 2003 x64 SP2
Windows Server 2003 SP2 for Itanium-based Windows Vista
Windows Vista SP1
Windows Vista SP2
Windows Vista x64
Windows Vista x64 SP1
Windows Vista x64 SP2
Windows Server 2008 for 32-bit
Windows Server 2008 for 32-bit SP2
Type:
Remote
Identifiers:
CVE-2009-1926
Synopsis
Microsoft
Windows TCP/IP is prone to a denial of sercie vulnerability due to an
error in the processing of specially crafted packets with a small or
zero TCP receive window size.
The vulnerability is due to the Windows TCP/IP
stack allowing connections to hang indefinitely in the FIN-WAIT-1 or
FIN-WAIT-2 state under certain conditions. 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.
