| 1.Summary
Backdoor.AckCmd is a Trojan Horse that uses TCP ACK segments
to
communicate. This Trojan may bypass firewalls that do not keep
track of
the session state in a TCP transaction.
2.Impact:
Possible theft of data and control of the targeted machine
leading to a
compromise of all resources the machine is connected to. This
Trojan
also has the ability to delete data, steal passwords and disable
the
machine. Other versions are capable of launching DDoS attacks.
3.Detailed Information:
This Trojan affects the following operating systems:
Windows 95
Windows 98
Windows ME
Windows NT
Windows 2000
Windows XP
No other systems are affected. This is a windows executable that
does
not make changes to the system registry.
AckCmd is a "proof of concept" Trojan.
4.Attack Scenarios:
This Trojan may be delivered to the target in a number of ways.
This
event is indicative of an existing infection being activated.
Initial
compromise can be in the form of a Win32 installation program
that may
use the extension ".jpg" or ".bmp" when delivered via e-mail for
example.
5.Ease of Attack:
This is Trojan activity, the target machine may already be
compromised.
Updated virus definition files are essential in detecting this
Trojan.
6.Corrective Action:
Delete the file AckCmd.exe
A machine reboot is required to clear the existing process from
running
in memory.
In addition, the use of a firewall that correctly checks the
state of a
TCP session is recommended. |
