How Does a Trojan Horse Work?
In Greek mythology, the story of the Trojan Horse is a tale from the Trojan War in which the Greeks waged war with the city of Troy. After a fruitless ten-year campaign, the attackers decide to build a huge wooden horse as a gift for the Trojans. Fooled into accepting the gift, and seeing no sign of the Greek army, the Trojans wheel the horse into Troy – only for a platoon of Greek soldiers to emerge from within later than night and open the gates to the city, letting in the rest of the army.
The analogy with software Trojans is clear – it represents a backdoor into your PC via a method that appears trustworthy, but in actual fact is usually destructive if not quickly countered.
Trojans can be acquired in the following ways:
• Email attachments.
• Application exploits, such as vulnerabilities in web browsers or messaging clients – regular Windows Updates should prevent exposure to this method. See Solving Windows Security Problems by Checking for Updates for more on this.
• A common method with the arrival of highspeed internet is via websites containing executable content, such as ActiveX. A competent Internet security suite should provide protection in conjunction with an up to date browser.
• Finally, software downloads from either hosting sites or filesharing networks can be laced with a variety of malware, including Trojans.
Each of these methods can include one or more overwhelming intrusions upon your computer security.