Computer Virus is a common issue which most of us faces now days and tries to use one the best anti- virus according to our data and computer needs .Computer virus is a virtual disease which can affect the computer in various ways for example, making files corrupt, slowing down the speed of the computer in processing or operating, deleting important files, making the computer held for longer times without any reason, but there are some viruses which have stroked the computers of the world in a very bad way. Although there are millions of types of viruses but there are some viruses which made their name and made a huge loss to the world.
Some of the computer viruses which can be considered in the list of top 10 worst computer viruses of the world are these.
10. Melissa
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| Melissa |
As the name looks very attract full and interesting but in reality it was one of the earliest mass mailing virus which was created by David L Smith. He created Melissa in the memory of a famous lap dancer who he liked. When computer is affected by Melissa virus it targets mainly the Microsoft office files and then generates the emails and sends then itself by using Microsoft outlook. Later on David L Smith was arrested and fined $5000 and spend 20 months in Prison.
9. ILOVEYOU
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| ILOVEYOU |
It has been heard and told that these 3 words change the meaning of life but when it comes to a virus trust me it’s something very harmful for your computer. ILOVEYOU comes in a form of email with attachments on its backend and when the user see the mail with a title written ILOVEYOU on it, obviously it creates curiosity and encouragement to check and the user opens the mail. Its actually a blank mail and ILOVEYOU spreads in to the computer and becomes a hidden file in almost all the folders of the computer in result of slowing down the computer or corrupting a huge amount of important data or files.
8. The Klez Virus
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| Klez |
The Klez is a computer Virus which spreads through email having one or couple of attached files which spreads like fire in the computer and start damaging files again and again. Sometimes the antivirus is not able to fix it. Once The Klez Virus spreads in the computer then it starts sending emails and instant messages to the contact list or address book. The Klez also spreads instantly over the shared network folders and can damage files on them.
7. Code Red and Code Red II
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| Code Red and Code Red II |
Code Red and Code Red II is one of the most dangerous virus existed in history. When the servers or computers infected by Code Red and Code Red II then something appears on your computer screen or LCD like this Hello, Welcome to http://www.worm.com .one of the major loss done by this virus is this that it infected the white house computers as well. The approximate damage caused by Code Red and Code Red II to the world is more than $2.5 billion.
6. Nimda
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| Nimda |
Nimda is a virus which has stroked most of the computers of the world and it was first occurred in 2001 and affected windows severely. If we do some math and calculate the total damage caused by Nimda then the value on the rough end is more than $620 million. The main targeted victims of this virus were internet servers and websites. Nimda also spread through email.
5. SQL Slammer/Sapphire
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| SQL Slammer/Sapphire |
SQL Slammer/Sapphire is one of the most serious and dangerous virus till now. On 25
th January 2003 it attacked the world very fast and within 10 minutes it affected 75000 + computers worldwide. The targeted victims of this virus were mostly the internet hosting companies and it also slowed down the speed of internet.
4. MyDoom
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| MyDoom |
MyDoom is a type of email computer virus and spreads all over the computer very fast. In MyDoom a file is attached to the email which gets downloaded automatically at the time when user opens the email or clicks on the email. After that MyDoom starts to expand from pc to pc sharing programs and it is very dangerous for computers running on Windows. MyDoom has caused a serious loss in internet history in 2004 by making the internet speed as slow as to 50 %.
3. Sasser
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| Sasser |
Sasser virus has also been famous all over the world. Sasser spreads throughout the computer in very less period of time. Although it can be stopped by a firewall. This virus has caused a huge loss to many big companies. When a computer in affected by Sasser mostly it happens that the computer gives an error of restarting after one minute itself and there is no way to stop it whatever work you are doing that has to be closed before one minute so that the data should not be lost.
2. Leap-A/Oompa-A
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| Leap-A/Oompa-A |
Leap-A/Oompa-A was created in 2006 and is considered as one of the most dangerous viruses of the world. Leap-A/Oompa-As has a way of affecting system through ichat instant messaging. After the Leap-A/Oompa-A affects the system it search for other computers through ichat contacts and then send them a simple jpeg picture file which looks a common file but on the back end of the file there is Leap-A/Oompa-A.once the user or viewer accepts the file then the virus is transferred in to his system and this happens so on. That’s why for internet securities don’t accept picture files from unknown people.
1. Storm Worm
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| Storm Worm |
In the ranking list of top 10 Storm Worm is the most dangerous computer virus which came in the history of internet. It used to come with the emails and the time when you open the email Storm Worm spreads in the entire computer and start destroying important files and documents in your computer hard drive. Once your computer is affected by Storm Worm then there is a huge loss in terms of valuable files and data.
Posted By
Armaghan Naeem
