Trojans are malicious applications that pose themselves as legitimate software in order to trick users to install them. Once on the victim's machine, it may run any number of malicious process to steal vital information or inflict damage to other software.
BackDoor.Multi is a IRC backdoor Trojan , which runs continuously in the backdrop, providing a backdoor server on port 6667. It connects to an Internet Relay Chat (IRC) server and joins a specific channel, where it listens for instructions. The supposed instructions are implemented locally on affected machines.