Computer Trojans

Introduction

The term Computer Trojan has often been used interchangably with the term Computer Virus, but in reality has slightly different characteristics. Trojan computer infections are named after the Ancient Trojans who believed the giant horse left behind by the Greeks was a peace offering after years of war. They happily accepted the free gift and brought it inside the walls of their city. Greek invaders hiding inside the horse waited until night, slipped out and opened the front door so the rest of the invaders could come inside the city and take over. This is essentially the way a computer trojan works, you think you are getting something for free (music, smilies, pirated software etc.) and you end up with a bunch of nasty programs on your computer.

Technical Information

The Trojan horse is basically a malicious program accompanied by spyware which you get through email attachment, a messenger program, or from an internet download. Trojans sometimes masquerade as a free program you would like. Once you accept the Trojan into your computer, it will perform a basic installation of itself. Typically, trojans tend to do the following:

Aid in hijacking your web-browser. This means that when you want to go to a particular homepage such as Google or MSN, you end up somewhere else.

Record your keystrokes and transmit it to the attacker. This gives them access to any password protected accounts you have set up, including banking and other sensitive data.

Do malicious functions such as rebooting your PC or deleting something.

Allow the attacker access to your PC to run other code.

Become a spam relay - sending vast amounts of spam to everyone else.

The main difference between a computer virus and a computer trojan is that a Trojan does not try to replicate itself.

Trojan Demo

This demonstration will show you some of the capabilities of Trojan horse programs. For this demo we have used the well known Sub Seven Trojan (aka Backdoor). The reader should be aware that this demo only outlines some of the more popular Trojan functions. This demo is only provided as a brief outline of what some Trojans allow the Hacker to do. Trojans become more advanced every day. Trojan programmers are always on the lookout for new startup methods as well as ways to get around both hardware and software firewalls.

It has become increasingly obvious that the general public awareness is very low in this key area of Internet security. Most Internet users do not even know what a Trojan horse is, let alone the high danger potential that these type of programs possess.

Method of Infection

Infection usually occurs with the consent of the victim, giving permission to download and open a program when visiting a website. It can also be transmitted via email attachment or IM chat program.

Detection and removal

Most anti-virus programs and some anti-spyware programs will detect most known Trojans. If you believe you have a computer Trojan that is not being detected, you can have a technician verify and remove the trojan from your system.

TrojanScan
Use this FREE online service to scan your computer for Trojans.

Most virus scanning programmes protect against worms.

Active Virus Shield
AntiVir Personal Edition
Comodo AntiVirus - Eliminates all known viruses, worms and Trojans. On-demand and On-access scanning, email scanning, process monitoring, worm blocker, scheduling & more. It’s easy to use; doesn’t slow down your PC and is free for life to the end user.
ProcessGuard is a powerful new cutting-edge program that greatly increases the security of your computer by preventing processes from being able to attack each other. It is considered by experts to be a must-have program for all users of Windows, and is the only program available that can prevent the infection of all known rootkit trojans.

What is a Rootkit?
The term rootkit is used to describe the mechanisms and techniques whereby malware, including viruses, spyware, and trojans, attempt to hide their presence from spyware blockers, antivirus, and system management utilities. There are several rootkit classifications depending on whether the malware survives reboot and whether it executes in user mode or kernel mode.

Source : This article originally appeared in www.yourtechonline.com
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