The word "Computer Virus" really scares all computer users. As we all know, Viruses can cause a lot of damage to the computer. It can damage victims privacy, can access private files and can even corrupt the very precious data which includes photos, videos, saved passwords etc. Computer viruses have already caused many financial losses for many companies. Sometimes it is good to look at the past and take a look at the viruses that caused widespread destruction that can make you conscious of computer viruses. Following are the 10 most destructive computer viruses of all time.
It is the computer worm that attacked more than ten millions of windows personal computers. The virus started to spread as an email message which includes a subject line "ILOVEYOU" and has the attachment of "LOVE-LETTER-FOR-YOU.txt.vbs". Once clicked it had the capabilities of forwarding itself to everybody in the victim's address book and proceed to overwrite files with itself which makes the computer unbootable. This virus was created by two Filipino Programers, Reonel Ramones and Onel de Guzman.
Yankee Doodle was first discovered in the year 1989 and it was actually created by a Bulgarian hacker. It is said when Yankee Doodle was executed, the virus itself becomes the memory resident. Yankee Doodle infects all .com and .exe files. The virus plays a tune "Yankee Doodle" itself every day at 4PM if it was in memory.
Nimda was first found in September 18, 2001. The name of the virus is derived from the word "Admin" if spelled backwards. Nimda used Emails, server vulnerabilities, shared folders and file transfer to spread itself. It became the internet's most widespread virus within 22 minutes. The main purpose of the virus was to slow down the internet traffic considerable causing a DoS attack.
In the year 1988 Robert Tappan Morris, the graduate student of Cornell University released the virus which affected approximately 10% of all the computers that were being connected to the internet. At that time 60,000 computers were attached to the internet and the worm infected 10% of them. The virus had the capability to slow down the computer up to the least point at which it becomes unusable.
Conficker which is also known as Downup, Downadup and Kido is a type of computer virus that usually targets Microsoft Windows Operating system. The virus was first identified in November 2008. This virus uses flaws of Windows operating system to fetch the administrator password via dictionary attacks while forming a botnet. This virus infected millions of computers which include government, business and home computer in over 190 countries.
The Storm Worm is a backdoor trojan horse that was identified in late 2006. Storm worm came in the spotlight when users started receiving e-mails with a subject line about a recent weather disaster "230 dead as storm batters Europe". The Storm Worm virus easily tricks the victims to click on the fake links that were already infected by the virus turning any windows computer into a botnet. As of January 22, 2007, the Storm Worm accounted for 8% of all malware infections globally.
We all know about the Terminator, Skynet is a virus that was inspired from The terminator movie. It is a very kind virus which makes the victims PC slow very kindly as well as it turns the computer screen red and states "Don't be afraid. I am a very kind virus. You have done many works today. So, I will let your computer slow down. Have a nice day, Goodbye. Press a key to continue". This virus infects all .exe files on the computer.
This is a type of trojan horse malware that spreads mainly through drive-by downloads and phishing schemes. It was first recognized in July 2007 when it was mainly used to steal information from the United States Department of Transportation. Zeus virus is very tough to detect because it uses some special stealth techniques that make difficult for an updated antivirus to detect it. Due to its special stealth techniques, this malware has become the largest botnet on the internet.
On 1st February 2004, approximately one million computers were infected with Mydoom's denial of service attacks and it was the largest such attack to the date. Mydoom virus spread through email which contains the text message "andy; I'm just doing my job, nothing personal, sorry". When the victim opens the mail the malicious code automatically downloaded and then steal the victim's whole contacts of email. From where it spread to the victim's friend, relatives, and colleagues.
SQL Slammer is the fast-spreading computer worm that infected most of its 75,000 victims within ten minutes. SQL Slammer dramatically slowed down general internet traffic and brought down South Korea's online capacity on Knees for 12 hours. SQL Slammer mainly targeted on the servers by generating random IP addresses and discharging the worm to those IP addresses.
Even if you are not a computer expert, you can protect yourself from viruses and worms before they reach your machine. Here are some tips that you can follow:
Keep an updated antivirus software installed and scan your computer
Do not open e-mails from external sources, don't open spammy links.
Allow Windows to update, many time windows updates bring some security updates that could fix the existing flaws from your computer
Don't download software from unreliable sources.