What is a computer virus? Top 6 Most Dangerous Computer Viruses of All Time?

If one day your computer suddenly restarts continuously, or maybe your computer hangs without any way to run smoothly even though you have checked and found that your hardware has no problems, then Has your computer ever been infected with viruses and what are they and what viruses on your computer will harm you? WebTech360 will introduce you to the top 6 most dangerous computer viruses of all time for you to know and find ways to avoid.

What is a computer virus?

Computer viruses (often referred to by users as viruses) are pieces of program code designed to do at least two things:

Interfere with the current computer's valid operation, to perform self-replication and other work as intended by the programmer. After the execution of the virus code is finished, control is returned to the executing process without the machine "hanging" , unless the virus intentionally crashes the computer.

Self-replicating, ie self-replicating, legally infects specific files (files) or regions (boot, FAT sectors) on storage devices such as hard disks, floppy disks, devices flash memory (commonly USB),... even the main EPROM of the machine.

In the past, viruses were often written by some knowledgeable people who wanted to prove their abilities, so often viruses took actions such as: for a program to not work properly, delete data, damage the hard drive, ... or make nasty jokes.

New viruses written in recent times no longer perform pranks or damage the infected victim's computer, but are mostly directed at stealing sensitive personal information (codes). credit card numbers) open the back door for hackers to gain control or other actions to benefit the virus spreader.

Over 90% of viruses have been found to target systems using the Windows family of operating systems simply because it is the most used operating system in the world. Because of the popularity of Windows, hackers often focus on them more than other operating systems. There is also a view that Windows has less security than other operating systems (such as Linux) so there are more viruses, but if other operating systems are as popular as Windows or the market share of horizontal operating systems Equally, the amount of virus appearing is probably about the same.

What is a computer virus?

Top 6 Most Dangerous Computer Viruses of All Time

1. Morris

Computer viruses are program codes written by organizations or individuals for malicious purposes such as feeding data, information, blackmail, etc., and are often infected via USB, Email, or over the network. Internet. Computer viruses are always hiding everywhere and can infect your computer at any time.

The first computer virus called the Morris worm was created by a Cornell University student. This virus was released online in 1988 and has caused a series of computer damage, estimated damage up to $ 100 million and this Morris worm can also be considered the most dangerous computer virus of all time.

This malware slows down thousands of computer systems by duplicating files in temporary directories. Once infected with the Morris worm your computer will be disabled too within 90 minutes. And it takes a lot of time for computer experts to completely remove this malware.

2. Melissa 

Melissa - the most dangerous computer virus of all time was created by a man named David L. Smith in 1999. Melissa computer virus was created from the idea of ​​​​based on macros in Word and this malware mainly weak are retrieved via email. This virus will entice you to open a document on email and when you open this file you accidentally activate the virus to replicate and it will automatically send to people around in the recipient email list.

The Melissa virus is spreading rapidly and damaging government private networks. This virus is so scary that Intel, Microsoft and other software companies have to shut down their email systems to avoid the damage that software brings. Total estimated damage that this Melissa virus brings up to 300-600 million USD, this is indeed the most dangerous computer virus of all time.

3. Code Red

Code Red is an extremely malicious and rapidly spreading computer virus in 2001. This worm mainly infects computers running IIS (Web Internet Information Server) network server software. The Code Red worm has the ability to find weaknesses on IIS to infect the virus, then they will continue to infect other failed servers. After about 20 days, this malware will attack and not allow DoS to access certain IP addresses, including the White House servers. In less than a week, the Code Red virus has infected more than 400,000 servers and the number of computers attacked by this virus shows no sign of decreasing.

4. Sasser and Netsky

Sasser and Netsky are two malicious programs created by Sven Jaschan in 2004. These two worms will have different ways of transmitting and causing harm. The Sasser worm will randomly scan IP addresses and trick you into downloading virus software to your computer. When malware is downloaded, it changes the operating system and makes it difficult to shutdown. For Netsky it will be transmitted by email. When entering the computer, this virus software will attack DoS and crash websites.

5. Storm Worm

Another most dangerous computer virus of all time is the Storm Worm. This virus attacked and infected millions of computers in 2006. The malware is spread by email by creating headlines that make readers curious and click on a link to watch. At this point, the malicious Storm Worm virus is downloaded to your computer, hackers can control your computer activities and spread spam emails everywhere.

6. Nimda

Nimda is also in the top of the most dangerous computer viruses of all time and raged in 2001. The speed of this virus is terrifyingly fast, with only 22 minutes it has been remembered by the whole world. The Nimda virus infects mainly servers, and sometimes they also infiltrate personal computers. The purpose is to cripple the internet and get personal information on the server. The attack of this malware has caused great damage to software systems and brought down a series of servers around the world.

Hopefully with the 6 most dangerous computer viruses of all time  you will know how to avoid hearing these names, all 6 of these viruses are really dangerous, so you should really take precautions to avoid making mistakes. Serious mistake, leading to computer problems. If you have any problems related to viruses, please contact  WebTech360 .