Wednesday, 18 Feb, 2009 Technology

The Most Dangerous Computer Viruses in History


Computer viruses have a relatively short history, but the damages caused by some of them pushed cyber-experts to opening a new chapter on computer viruses. Some viruses led to serious damages and affected a large number of companies, universities and even governments.

Here are some of the most dangerous computer viruses in history:

Jerusalem - 1987

This is one of the first MS-DOS viruses in history that caused enormous destructions, affecting many countries, universities and companies worldwide. On Friday 13, 1988 the computer virus managed to infect a number of institutions in Europe, America and the Middle East. The name was given to the virus after one of the first places that got "acquainted" with it - the Jerusalem University.

Along with a number of other computer viruses, including "Cascade", "Stoned" and "Vienna" the Jerusalem virus managed to infect thousands of computers and still remain unnoticed. Back then the anti-virus programs were not as advanced as they are today and a lot of users had little knowledge of the existence of computer viruses.

Morris (a.k.a. Internet Worm) - November 1988

This computer virus infected over 6,000 computer systems in the United States, including the famous NASA research Institute, which for some time remained completely paralyzed. Due to erratic code, the worm managed to send millions of copies of itself to different network computers, being able to entirely paralyze all network resources. The damages caused by the Morris computer virus were estimated at $96 millions.

To be able to spread, the computer virus used errors in such operating systems as Unix for VAX and Sun Microsystems. The virus could also pick user passwords.

Solar Sunrise - 1998

A decade later the situation didn't change, in fact it even got worse. Using a computer virus, hackers, in 1998, penetrated and took control of over 500 computer systems that belonged to the army, government and private sector of the United States. The whole situation was dubbed Solar Sunrise after the popular vulnerabilities in computers that run on the operating system called Sun Solaris. Initially it was believed that the attacks were planed by the operatives in Iraq. It was later revealed that the incidents represented the work of two American teenagers from California. After the attacks, the Defense Department took drastic actions to prevent future incidents of this kind.

Melissa - 1999

For the first time computers got acknowledged with Melissa computer virus on March 26, 1999, when the virus shut down the Internet mail system, which got blocked with e-mails infected by the worm. It is worth mentioning that at first Melissa was not meant to cause any harm, but after overloading the servers, it led to serious problems. For the first time it spread in the Usenet discussion group Melissa was hidden within a file called "List.DiC", which featured passwords that served as keys to unlocking 80 pornographic websites. The original form of the virus was sent through e-mail to different users.

Melissa computer virus was developed by David L. Smith in Aberdeen Township, New Jersey. Its name comes from a lap dancer that the programmer got acknowledged with while in Florida. After being caught, the creator of the virus was sentenced to 20 months in federal prison and ordered to pay a fine of $5,000. The arrest was made by a team of representatives from FBI, New Jersey State Police and Monmouth Internet.

Melissa had the ability to multiply on Microsoft Word 97 and Word 2000, as well as on Microsoft Excel 97, 2000 and 2003. In addition, the virus had the ability to mass-mail itself from Microsoft Outlook 97 and Outlook 98.

I Love You - May 2000

Using a similar method as the Melissa, the computer virus dubbed "I Love You" managed to infect millions of computers around the world overnight. Just like Melissa this computer virus sent passwords and usernames, which were stored on the attacked computers, back to the developer of the virus. After authorities traced the virus they found that a young Filipino student was behind the attack. The young man was released due to the fact that the Philippines did not have any law that would prevent hacking and spreading malware. This situation served as one of the premises for creating the European Union's global Cybercrime Treaty.

The Code Red worm - July 2001

This 21st century computer virus managed to penetrate tens of thousands of systems that ran Microsoft Windows NT and Windows 2000 server software. The damages caused by the Code Red computer virus were estimated at $2 billion. Core Red was developed to use the power of all computers it infected against the official website of the White House at a predetermined date. In collaboration with different virus hunters and tech firms, the White House managed to decipher the code of the Code Red virus and stop traffic as the malware started its attacks.

Nimda - 2001

Shortly after the September 11 tragedy this computer virus infected hundreds of thousands of computers worldwide. Nimda was considered to be one of the most complicated viruses, having 5 different methods of infecting computers systems and being able to duplicate itself.

Downadup - 2009

The latest and most dangerous virus is the "downadup" worm, which was also called "Conficker". The computer security company F-Secure stated that the computer virus has infected 3.5 million computers worldwide. This malicious program was able to spread using a patched Windows flaw. Downadup was so "successful" in spreading across the Web, because it used a flaw that Microsoft patched in October in order to distantly compromise computers that ran unpatched versions of Microsoft's operating system. But the greatest power of the worm is believed to be the ability of computers, infected with the worm, to download destructive code from a random drop point. F-Secure stated that three of the most affected countries were China, Brazil and Russia.

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52 votes

//76 Oct 18, 2012 01:26 AM | posted by: anoopmangattu [InfoTOT]
if the user is carefullll..... it"ll nt affect...
64 votes

//66 Feb 18, 2012 04:03 PM | posted by: beemparthiban [InfoTOT]
very nice topic..
62 votes

//55 Jan 07, 2011 05:45 AM | posted by: F Klein
LINUX. Non-administrator account. Wade through virus and spyware infected forests with NO FEAR.
74 votes

//54 Dec 18, 2010 09:34 AM | posted by: _e_JJ4K
65 votes

//53 Dec 07, 2010 03:30 AM | posted by: Spook
The other Day, I got a nightmare ... I was just staring near my computer but then I saw a thing saying VIRUS.bmp Installed succesfully and all I though was Oh no! but it was late and I saw all windows begin to open, Static appeared over the screen and Im not sure what I saw but I swear its the scariest thing i could have Imagined so I closed my Eyes and I heard a rough voice say "Awesome messenger Status mwhaahaha!!!"
Good thing it was just a Nightmare I think I got to buy ESET Right now XD!!!
77 votes

//51 Dec 03, 2010 01:58 PM | posted by: Deba
That's why we should use Linux kerneled OS
67 votes

//50 Nov 27, 2010 04:53 AM | posted by: dookie791
I can't believe it.........not even some of the lesser known, but dangerous viruses weren't listed? The ones that most don't even know ignorant people are. Google and antivirus software companies hire the best virus programmers (the maker of the nimda virus) to test the software and Google's security. A certain hacker found a glitch in Google's security. This hacker was able to access the computer of any computer that uses google.
The hacker could even penetrate the Pentagon security.
76 votes

//49 Nov 12, 2010 07:14 AM | posted by: ncusa
You mean to tell me that as smart as the scientific and computer communities are that they can't come up with a way to "bulletproof" our operating systems? Yeah right! The antivirus makers are probably the one's creating the viruses!
83 votes

//48 Sep 27, 2010 11:53 AM | posted by: Dan
Thanks for the comment.

You can repost the article only if you include a link to the original source, i.e.
71 votes

//47 Sep 25, 2010 10:35 PM | posted by: jlapitan [InfoTOT]
can i repost this article on my site?
70 votes

//46 Sep 25, 2010 10:31 PM | posted by: jlapitan
can i repost this article on my site?
72 votes

//45 Sep 24, 2010 08:10 AM | posted by: omkararuben
super comment
72 votes

//44 Sep 15, 2010 01:16 PM | posted by: karthi
i need more for this
77 votes

//43 Sep 08, 2010 11:47 AM | posted by: ARUN
the website has some information about virus and its effect
65 votes

//42 Sep 08, 2010 11:44 AM | posted by: KARTHI
68 votes

//41 Aug 18, 2010 07:45 AM | posted by: ryan
those trojans can be a b**ch. but those javascript redirectors are very hard to get rid of. javascript redirectors can redirect you to harmful pages and sometimes can just take you to some random site. or just close your browser. like, one second you are at google. then the js redir takes you to doing an automatic download.
71 votes

//40 Jul 02, 2010 02:18 PM | posted by: Manas
I need some more information.
Ok it's well.
I am select this as my seminar topic.
Virus maker be aware.
76 votes

//39 Jun 05, 2010 04:53 PM | posted by: Ben
Yes its pretty Frightening,I wonder what will be the next most dangerous virus called!!
72 votes

//38 May 21, 2010 02:59 AM | posted by: larbid
L2M is the most dangerous virus i didnt upload it it's in my 2nd pc is a virus can think by itself it have basics of human thinking in dangerous situation u mean my other pc alwys off if i used a bleutooth there it will send itself and upload itself in the net about the code to off it , i cant use it coz it know that it'll finish so it changed the code by itself
never say a virus can burn the hard disk can be dangerous
my virus have a brain it can do anthying
75 votes

//37 May 16, 2010 04:39 PM | posted by: nin
81 votes

//36 Apr 25, 2010 06:01 PM | posted by: david
why dont you have medesen for the computer
71 votes

//35 Apr 24, 2010 06:45 PM | posted by: jj
Nice info thanks for this information. I really needed information about viruses and all those things. Thnx!
74 votes

//34 Apr 21, 2010 08:01 AM | posted by: Mrxd15
75 votes

//33 Feb 22, 2010 01:10 PM | posted by: sowmya628762
i wsnt knwing dat dere r so many no no no....infinite viruses in dis computer world...i wish in d coming generation sme buddy shud free all dese wierd viruses using only 1 anti....i knw its so foolish bt jus think about it hw stress free it becomes :-p
70 votes

//32 Feb 06, 2010 07:24 PM | posted by: zuma dotch
i made about 6 viruses that hack millins of computer but i didnt send any one for my unkown software protection and
specific computer virus burners an damage of microprocessor i burned a computer of my friend after that i did not burn any ones computer to prevent harm worm spywares of password 56hp233nod32.exe virus
65 votes

//31 Feb 04, 2010 05:43 PM | posted by: kiki bad azzz
how can a computer obtain a virus
78 votes

//30 Feb 02, 2010 10:06 PM | posted by: josh
this may be the wrong way to think about such things, but thanks to the "virus Makers" i have a well paid and insured job!!!
71 votes

//29 Jan 31, 2010 03:40 PM | posted by: Admin
Download Zonealarm Firewall OR NOD smart security with valid keys only on
72 votes

//28 Jan 27, 2010 11:26 AM | posted by: g.nagaraj
its the best
67 votes

//26 Jan 21, 2010 10:18 PM | posted by: dod
if they don't make virus, Jackie chan has to cut down on donuts for tea time.
61 votes

//25 Jan 20, 2010 02:25 PM | posted by: gingee
there is too much information and too many long words for mje because im 13 can you make a like child section or summat daft so we can understand thiss too ,
68 votes

//24 Jan 19, 2010 09:59 PM | posted by: lizzie
hi i was wondering if you could help?
i need to find out whay viruses, trojan horses and worms are so dangerous!
68 votes

//23 Jan 15, 2010 11:41 PM | posted by: Chay
74 votes

//22 Dec 24, 2009 06:04 AM | posted by: jennifer lobrigo
what's ur purpose and ur creating virus???
69 votes

//21 Dec 08, 2009 01:24 AM | posted by: ImbA
I would say...viruses..hmm funny..some1 should make a virus that would destroy every computer on this world that is connected to the internet : why?
the world is just going down and down and we will burn in Hell
we really dont need those things let's use horses to deliver letters or some pigeons hehe :D that would be more creative hehe
72 votes

//20 Dec 06, 2009 05:15 PM | posted by: Techno_Girl [InfoWILD]
After reading this article, I realize I scary viruses can be. It makes me feel that I have to download as many anti-virus soft wares as possible, to avoid all of these deadly viruses.
72 votes

//19 Nov 06, 2009 07:39 PM | posted by: fail
"devil_virusmaker "
Never make an account on a website you're going to hack...or at least hack it on a different ip, although it's still easily traceable.
As far as I can tell, you're just some 30 year old getting humor from this
78 votes

//18 Sep 15, 2009 01:49 AM | posted by: Swati
If you cant be CONSTRUCTIVE

As such no comment for you virus cant help yourselves
76 votes

//17 Aug 20, 2009 08:08 PM | posted by: Aisha
what i gat to say i dat viruses are harmful to the system and the writer of this so called virus programmer should be help on d issue of viruse
64 votes

//16 Aug 19, 2009 02:34 PM | posted by: whella [InfoBIG]
well! all i can say to this virus, so scary. To all virus maker did you ever try to made a "GENERAL ANTI-VIRUS" that could ignore all kinds of harmful virus.What ever kinds of virus is that, could say nothing to this anti-virus.I'm just asking!
78 votes

//15 Aug 16, 2009 10:21 AM | posted by: tvt rockz
dai devil maker .. u r a comedy man da... i will send u a virus.. soon man...
71 votes

//14 Aug 13, 2009 01:36 AM | posted by: Appleton
Me and My team are working on a program, a virus that would infect all computers worldwide. It will not cause any harm, only benefit them. We are good people, and so we will design a program, a virus as an experiment. The program will detect the activities of people. And with in a month, it will create statistics as to what people do on the computer and how these computers are really being used.
BY doing this experiment, we will be able to figure out the activities that people enjoy the most. We will also be able to discover things that people buy the most online. And so, this program will actually help us obtain 'real' statistics, which we will use to built websites and businesses.

So, not harm, just a survey type program.......
70 votes

//13 Aug 12, 2009 12:16 PM | posted by: whella
its nice!but then theres no harmful virus in every computer if the user is careful.
87 votes

//12 Aug 10, 2009 11:48 AM | posted by: roscoe
Well this just a signs that people really knew to grow and learn on how to irritate and terrorize peoples on the net. It's just really sucks if you didn't know when they are going to hit you. But the variable solutions that you can see is by the help of the net.
75 votes

//11 Aug 05, 2009 07:29 PM | posted by: Neko.gen
Those are just very few from the real deal's o,o
82 votes

//10 Aug 05, 2009 05:46 PM | posted by: dragan
what a world
83 votes

//9 Jul 28, 2009 07:10 AM | posted by: enesmo 818
fuck all you virus you bicths shoud kill your self you guy are just making people spend more money and some people dont have virus blocking i hope you guys kill your self
76 votes

//8 Jul 26, 2009 06:57 PM | posted by: Jim
Virus writers should be shot in the face and then buried alive.
101 votes

//7 May 25, 2009 01:47 AM | posted by: kudude63 [InfoBIG]
//4, why the fuck?!?! r u kidding me? u send 1 to email and i download it! u cant stop my antivir/antimalware shit! (u r stoopid person if u say that and not back it up!)
71 votes

//6 May 25, 2009 01:43 AM | posted by: kudude63 [InfoBIG]
no i havnt seen yahoo virus, i wanna download viruses to test Trustware Bufferzone and see if the company's claim that if it can't stop a virus or other stuff u get 500 bucks
76 votes

//4 Apr 06, 2009 03:05 PM | posted by: devil_virusmaker
...those are such weak viruses compared to what i did...
.yah i'm a virus maker...
....and i have invented a new one..
..this one is the most dangerous of all..'s called "John's Face Virus".... careful of it!............
....i'll start putting some of it in this website.....
..maybe next week!..
101 votes

//3 Mar 27, 2009 11:32 AM | posted by: Geoge
Wow that is some really load of Viruses. By the way nice history report you really remind me of those scary threats.
92 votes

//2 Mar 23, 2009 07:24 PM | posted by: gordon
78 votes

//1 Mar 12, 2009 12:23 PM | posted by: sanam
how r u

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