Trojan Education

The word Trojan originally came from early Greek history. Remember the giant wooden horse which was given as a gift only to find out later it was a trick and concealed something else. A computer Trojan uses the same type of technique whereby disguising itself under a different program name. Computer Trojans are typically disguised with attractive names which trick you into downloading them from the internet and running them. They can be disguised as that neat little utility program you always wanted or a checkers game or whatever promises to perform a useful function. Once run, the program secretly implants the Trojan program into your operating system.

Trojans are generally communications programs which are implanted to communicate thru the internet with someone at some remote location. The communication is performed thru a port which has been opened by the Trojan. A hacker scans IP addresses (computers connected to the internet) looking for the open port. Once found he can then communicate with the Trojan and instruct it to do his bidding. This includes downloading files, running other programs, getting stored passwords, sending emails, uploading files, displaying pictures or writing on your screen, and even opening your CD tray. These are the bad Trojans.

Other Trojans fall into a category called “spyware”. These are programs which are designed by businesses to collect information about you and your computer. Spyware programs typically install themselves by implanting a hook into the operating system service startup list which ensures they will be run every time the PC is turned on. Spyware enters either from web sites which use scripts to transfer itself or from purchased software. Yes purchased software! I’ve seen spyware programs planted when installing printer drivers, instant message programs, games and music download programs. This type of spyware usually just collects information about where you go on the internet, how much you print, how many emails you sent and so on. The information is then sent over the internet to the creator. This is not necessarily bad but a nuisance in that they take up hard disk space and processor time in your PC. Anti-Virus programs do find pretty much all the bad Trojans and viruses but, there are too many spyware programs to keep on top of so you are pretty much on your own if you want a completely clean system. Removing them is a matter of examining all running processes and deleting programs which are not legitimate operating system services.