Rule:

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Sid:
114

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Summary:
This event is generated when the Netbus trojan service is responding to 
an attackers commands on port 12346
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Impact:
Possible theft of data and control of the targeted machine leading to a
compromise of all resources the machine is connected to.
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Detailed Information:
The program is a backdoor designed for Windows. It allows anyone who
knows the listening port number and password to remotely control the 
host.  Intruders access the server using either a text or graphics based
client.

The backdoor program allows the remote user to execute commands, list
files, start silent services, share directories, upload and download
files, manipulate the registry, kill processes, list processes, as well
as other options, as well as open/close the CD-ROM drive, send
interactive dialogs to chat with the compromised system, listen to the
system's microphone (if it has one), and a few other features. 

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Affected Systems:
	Windows 95
	Windows 98
	Windows NT
	Windows 2000

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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 may be due to the exploitation of another vulnerability and
the attacker is leaving another way into the machine for further use.

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Ease of Attack:
This is Trojan activity, the target machine may already be compromised.

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False Positives:
Security tool probing for netbus
Other services configured for 12346

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False Negatives:
None Known

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Corrective Action:
Disallow Telnet access to port 12346 from external sources.

Use SSH as opposed to Telnet for access from external locations

Delete the Trojan and kill any associated processes.

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Contributors:
Original rule writer unknown
Snort documentation contributed by John Liss
Sourcefire Research Team
Nigel Houghton <nigel.houghton@sourcefire.com>

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Additional References:

NetBus
http://www.ntsecurity.net/

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