The 5 most dangerous viruses of all time and what they did
Similar to humans, there are dangerous viruses on computers. Their malice can be measured by their aggressiveness, but above all by the damage they do. We have put together the top 5 most dangerous viruses for you. We have chosen the damage caused and the number of people affected as criteria. Hopefully you only know her from theory.
Dangerous beasts: a little virus science
The terms "virus", "worm", "backdoor", "rootkits" and "trojans" are often lumped together. They are all malware and therefore dangerous malware. Nevertheless, one should differentiate. From the beginning, Microsoft Windows was the most popular target of Malware - and still is today.
- In the beginning was ...: the virus. It can spread itself, but needs a host program. A virus "infects" a file, such as an EXE file. That means he adds code to this file. The virus is then spread via the transfer of the file.
- A worm, on the other hand, doesn't need a host. Once on the computer, it uses its own SMTP server and sends itself to all mail addresses that it finds on the computer.
- A Trojan, on the other hand, does what its name suggests: it disguises itself as useful software. You can imagine that it is not. Once released, it wreaks havoc.
- A backdoor uses a "back door", a loophole, to get to the PC. This is usually just one line in a PHP script. Either the hacker is involved in the development of a software or he uses a trojan. In any case, the hacker has permanent access to the computer with a backdoor.
- A rootkit is the burglar’s crowbar, so to speak. He uses security gaps in operating systems and software and thus gains administrator rights.
5th place: SLAMMER
Slammer is a worm and was released in 2003. Like many viruses, the Slammer has different names. It is also known as SQL Slammer, Sapphires, WORM_SQLP1434.A, SQL Hell or Helkers.
- Slammer quickly infected around 200, 000 computers. The damage that was caused is estimated at $ 1.2 billion.
- The target was database servers on which Microsoft SQL Server 2000 was installed. Spreading should have been avoided. Microsoft had already released a patch for the vulnerability - only many had not installed it.
- Slammer sent a flood of data, slowing the Internet down significantly. Some hosts have stopped completely. The server of a US nuclear power plant was also affected - the security system was paralyzed by Slammer.
4th place: CODE RED
The name sounds threatening, so is the worm. In 2001, it sneaked through a security hole in Microsoft's Internet Information Server and spread from one web server to the next.
- The goal of the worm was to change websites.
- He also launched so-called DDoS attacks against certain IP addresses. DDoS attacks are designed to override availability. The best-known victim of such a Code Red attack was the White House server.
- Code Red infected 400, 000 servers in just one week. A total of 1 million PCs were affected and the damage was about $ 2.6 billion.
3rd place: ILOVEYOU
ILOVEYOU, also known as Loveletter, is unfortunately not a declaration of love, but also a computer worm. In the delightful month of May 2000, many Internet users received an email with a declaration of love attached. The joy lasted only briefly - as soon as the supposed lover opened the mail, the virus settled in the mail program and on the hard disk.
- The virus then spread itself: It was sent as an email to the first 50 contacts in the address book.
- The Loveletter overwritten image files and also stole passwords from the computer.
- The only good thing about ILOVEYOU was that with this worm, users really became aware of malware for the first time and developed an awareness of security software.
- The worm "only" infected 500, 000 computers, but caused a total damage of a whopping 15 billion US dollars. ILOVEYOU originated in the Philippines. There, three people were also suspected of having programmed the worm. The authors had no consequences anyway: At that time there was no law against the development of computer viruses in the Philippines.
2nd place: SOBIG.F
Sobig.F is both a self-copying worm and a Trojan, and was released in August 2003.
- With 2 million infected PCs and more than $ 37 billion in damage, Sobig.F ends up just behind number one on our list of horrors.
- It was fast, you have to let Sobig.F: within 24 hours the pest sent a million copies of itself.
- Not only was the inbox overwhelmed by the flood of emails. The huge data traffic also brought many systems to their knees. In Washington DC, for example, it was no longer possible to send mails or data traffic for a short time. Many company computers worked extremely slowly. Air Canada even had to cancel some flights because of Sobig.F.
- Microsoft had suspended a $ 250, 000 bounty to find the author. In vain - the developer of Sobig.F is still unknown.
- Sobig.F disappeared from the scene on September 10, 2003.
1st place: MYDOOM
And the winner is: MyDoom - in a negative sense, of course. Mydoom is also a worm and was in trouble from January to February 2004. Then Mydoom disappeared again.
$config[ads_text6] not found- Mydoom spread through a so-called bounce message. These are non-delivery notifications that a mail server creates when a mail cannot be delivered. If the user clicked on this mail, the computer was infected. The worm then sent itself to all contacts that it found in Windows.
- Mydoom slowed down the Internet by around 10% overall and website load times by 50%. The high point of the activity was on January 26, 2004: for a few hours, the effects were felt worldwide.
- 2 million computers were infected. The damage that Mydoom did in just a few weeks is a whopping $ 38 billion.
- Microsoft also issued a quarter of a million dollars in bounty on MyDoom.
Out of competition: the Stuxnet worm
Not in our ranking, but worth mentioning is the Stuxnet computer worm. It shows quite impressively what malware can do and what malware is used for - as a weapon in cyber war. The worm was most likely programmed by a government organization. The USA and Israel are suspected.
- Stuxnet also used security holes in Microsoft Windows to penetrate a system. When the worm was discovered in June 2010, it had actually done its job.
- The Siemens control system, which was responsible for the speed of the turbines in the Iranian nuclear power station Buschehr, was manipulated by Stuxnet. The result was that the turbines sometimes turned too fast, sometimes too slowly and were therefore destroyed.
Current threat: WannaCry
The virus "WannaCry", which is currently spreading rapidly, is also dangerous. Read what this ransomware does and how to protect yourself in this post.
Viruses, Trojans & Co will always be there, and new malware will appear again and again that can infect your computer. For this reason, we have tested numerous virus scanners for you.