Worst Computer Viruses

Obtaining a computer virus has occurred to a lot of users in some manner or another. To most, it’s merely a mild annoyance, requiring a cleanup and then installing that antivirus program that you have been meaning to put in but not got around to.

However, in other situations, it can be a total disaster, with your computer turning into a really costly brick that no amount of antivirus may shield.

In this list, we’ll highlight a few of the worst and most infamous computer viruses that have caused plenty of harm in real life. And because people usually equate general malware such as worms and trojan horses as viruses, we are including them too. This malware has caused enormous harm, amounting to billions of dollars, and interrupting critical real-life infrastructure.

ILOVEYOU
ILOVEYOU is regarded as among the most virulent computer virus ever made. It was able to wreak havoc on computer systems all around the world with approximately $10 billion worth of damages. 10 percent of the world’s computers were considered to have been infected. It was so bad that governments and huge corporations took their mailing system offline to prevent disease.

The virus was made by two Filipino programmers, Reonel Ramones and Onel de Guzman. What it did was use social engineering to get people to click on the attachment; in this situation, a love confession. The attachment was actually a script which introduces as a TXT file, because of Windows in the time hiding the true extension of the document.

Once clicked, it will send itself to everyone in the user’s mailing list and proceed to overwrite files with itself, which makes the computer unbootable. Both were never billed, as there were no laws about malware. This led to the enactment of this E-Commerce Law to address the problem.

Code Red
Code Red first surfaced in 2001 and has been discovered by two eEye Digital Security employees. It was called Code Red since the pair were drinking Code Red Mountain Dew in the time of discovery.

The worm targeted computers using the Microsoft IIS web server installed, exploiting a buffer overflow problem in the system. It leaves a very little trace on the hard disk because it’s ready to run entirely on memory, with a size of 3,569 bytes.

Once infected, it is going to go to make a hundred copies of itself due to a bug in the programming, it is going to replicate more and ends up eating a lot of the systems resources.

It will then establish a denial of service attack on several IP addresses, famous among them was the assault on the White House site. Additionally, it allows backdoor access to the host, allowing for remote access to the machine.

The most memorable symptom is that the message it leaves on affected webpages,”Hacked By Chinese! A patch was later published and it was estimated that it generated $2 billion in lost productivity. A total of 1-2 million servers were changed, which is awesome when you think there were 6 million IIS servers at the moment.

Melissa
Named after an exotic dancer from Florida, it was produced by David L. It began as an infected Word document that was posted up on the alt.sex Usenet group, claiming to be a list of passwords for pornographic websites. This got people curious and if it was opened and downloaded, it would activate the macro inside and unleash its payload.

The virus will email itself into the top 50 people in the consumer’s email address book and this caused a rise of traffic, interrupting the email services of corporations and governments. Additionally, it sometimes corrupted documents by adding a Simpsons reference.

Smith was eventually caught when they tracked the Word document. The file was uploaded with a stolen AOL account and with their aid, law enforcement was able to detain him less than a week since the outbreak started.

He cooperated with the FBI in catching other virus founders, famous among them the founder of the Anna Kournikova virus. For his cooperation, he served just 20 months and paid a fine of $5000 of his 10-year sentence. The virus allegedly caused $80 million in damages.

Sasser
A Windows worm first discovered in 2004, it was produced by computer science student Sven Jaschan, who also created the Netsky worm. While the payload itself can be viewed as simply annoying (it slows down and crashes the computer while making it tough to reset without cutting the power), the effects have been incredibly tumultuous, with millions of computers being infected, and significant, critical infrastructure changed.

The worm took advantage of a buffer overflow vulnerability in the Local Security Authority Subsystem Service (LSASS), which controls the security policy of local accounts causing crashes into the computer.