Such Trojans directs the victim machines to infected resource over the Internet where the machine can be attacked by other malwares. At times, Trojan clickers are also used to raise the hit counts or to organize a Denial-of-Service (DOS) attack on a specified website.
Backdoors
Back door Trojans are the most widely spread Trojans. They function as legal remote administration programs and thus are very difficult to be detected. They are launched and executed without the consent or knowledge of the user. On the execution of a specific command by the master, it opens your computer to an infected machine and starts performing actions such as launching/executing files on its own, deleting your favorite applications, displaying notifications, delete data or automatically reboot your computer.
PSW Trojans
PSW Trojans steal system details such as memory, disk space, operating system details, IP address, system password, online games password, and other types of passwords present on the victim machine. Such Trojans search for system files that comprise of password details and this information is sent across to the hacker or intruder from an e-mail address coded in the body of the Trojan.
General Trojans
General Trojans threaten data integrity or cause valuable destruction on the victim’s machine such that the computer starts malfunctioning. A few examples of general Trojans are BAT.Adduser.t, AOL.Win32.Buddy.a and SMS.SymbOS.Viver.a.
Trojan Downloaders
Trojan Downloaders, as the name suggests, installs new malware on the victim machine without the knowledge of the user. This Trojan comprises a list of names and locations of malwares that are to be downloaded from a specific website or any other location.
Trojan Proxies
When installed on a victim machine, Trojan Proxies provides access to the Internet from the victim machine to spammers. This helps the spammer in mass mailings.
Trojan Droppers
Trojan Droppers drop a hoax to divert the user’s attention in form of a joke, games or graphics. While the user is busy in viewing the hoax, it implants payload at a specific location and then launched. Because of its hoaxing activity it fools the anti-virus solutions that fail in detecting such viruses.
Rootkits
Rootkits replaces system files or libraries to gain unauthorized access to a computer. It is implanted after cracking the user level access password without the knowledge of the user of victim machine.
Trojan Spies
As its name suggests, it spies over the actions of the user on the victim’s machine and records every bit of the details on the PC and forwards it to the hacker. Trojan Spies collect information like screenshots, logs of active applications, keystrokes, financial and banking information.
ArcBombs
ArcBombs are archived files that are coded to cause system crash, slow downs or fill up hard disk with unwanted data. On being detected by an anti-virus or de-compressor, if it is tried to open, it explodes and causes massive destruction. It is very risky for servers if they get infected by ArcBombs.
Trojan Notifiers
Trojan Notifiers informs the creator the victim machine has been successfully infected. These Trojans send information such as open port numbers, e-mail address, IP address etc to the hacker through e-mail or through chat programs like ICQ.
