Some Malicious Computer Viruses

A computer virus is a computer program or programming code which can replicate itself from one folder to other folder and one computer to other computer. A properly engineered virus can cause a huge damage, e-g, in January 2004, a virus name Mydoom Worm infected approximately a quarter-million computers just in a single day. Trojan horses, Worms, spywares and rootkits are different forms of virus. A virus can be spread through E-mails, removable media like CD, DVD, USB drive and through other computers on same network. Following are some most dangerous Viruses which caused a lot of damage.

CIH: CIH is also known as Chernobyl, is a virus coded by Chen Ing Hau of Taiwan. It was one of the most damaging viruses at its time which used to overwrite critical information on infected system drives and in some cases system BIOS was also corrupted. This virus caused a huge loss in Asia.

ILOVEYOU: also known as Aric Paul, is a computer worm that attacked tens of millions of computers in 2000 through email. It was an email with subject "ILOVEYOU" having an attachment "LOVE-LETTER-FOR-YOU". After opening the attachment, this worm used to send a copy of itself to all the email addresses on the Windows Address Book and with the user's sender address. This virus also caused several malicious changes to the computers.

Fun.exe (New Folder): was first apperaed in 2008. This virus installs multiple copies of itself throughout the system on different locations with different names, its icon is just look like a folder, and upon clicking it starts working and making copies in all folders. It is nearly impossible to delete them.

Backdoor.Win32.IRCBot (MSN Messenger Fame): is a backdoor computer worm that is spread through MSN Messenger and Windows Live Messenger. Once it is installed on a computer, it copies itself into a Windows system folder. It send itself to all MSN Contacts offering them to open an attachment "photos.zip" or click on a link with a personal message like
"Hey, is this your picture? :S http://www.msnimages.net/images/viewimage.php?=abc@hotmail.com".
This worm is also used  by hackers as it allows for confidential information to be transmitted to a hacker.