Rule: -- Sid: 114 -- Summary: This event is generated when the Netbus trojan service is responding to an attackers commands on port 12346 -- Impact: Possible theft of data and control of the targeted machine leading to a compromise of all resources the machine is connected to. -- 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. -- Affected Systems: Windows 95 Windows 98 Windows NT Windows 2000 -- 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. -- Ease of Attack: This is Trojan activity, the target machine may already be compromised. -- False Positives: Security tool probing for netbus Other services configured for 12346 -- False Negatives: None Known -- 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. -- Contributors: Original rule writer unknown Snort documentation contributed by John Liss Sourcefire Research Team Nigel Houghton <nigel.houghton@sourcefire.com> -- Additional References: NetBus http://www.ntsecurity.net/ --