Most PCs are now connected to the Internet and networks, making easier the spread of malicious software (malware), which includes trojans (also known as trojan horses), viruses, worms, spyware, adware, rootkits and other malicious or unwanted programs.
Like spyware and adware, trojans can get onto your computer in a number of ways, including from a web browser, via e-mail, or in a bundle with other software downloaded from the Internet. You may also inadvertently transfer malware via a USB flash drive or other portable media. It is possible that you could be forced to reformat your USB flash drive or other portable device in order to eliminate the infection and avoid transferring it to other machines. (After all, you don't want to be the one who infected your network at work because you were bringing in some music to listen to.)
Unlike viruses or worms, trojans do not replicate themselves but they can be just as destructive. On the surface, trojans appear benign and harmless, but once the infected code is run, trojans kick in and perform malicious functions to harm the computer system without the user's knowledge.
For example, waterfalls.scr is a waterfall screen saver as originally claimed by the author, but it can be associated with malware and become a trojan to unload hidden programs and allow unauthorized access to the user's PC.
Some typical examples of threats by trojans are as follows:
1.Erase, overwrite or corrupt data on a computer
2.Help to spread other malware such as viruses (by a dropper trojan)
3.Deactivate or interfere with anti-virus and firewall programs
4.Allow remote access to your computer (by a remote access trojan)
5.Upload and download files without your knowledge
6.Gather e-mail addresses and use them for spam
7.Log keystrokes to steal information such as passwords and credit card numbers
8.Copy fake links to false websites, display porno sites, play sounds/videos, display images
9.Slow down, restart or shut down your computer
11.Re-install themselves after being disabled
12.Disable the task manager
13.Disable the control panel
0 comments:
Post a Comment