Today’s internet-connected society is plagued with costly and destructive computer viruses. Every day, more than 350,000 new malware samples are found, costing an estimated $55 billion annually. And, some of Most Dangerous Computer Viruses of all Time generated damages reaching billions of dollars each. When the stakes are this great, being cautious pays off. It might be challenging to take network security seriously, though, unless you are aware of your adversaries.
This article lists the most financially damaging computer viruses. However, keep in mind that these harmful applications are only the beginning. The viruses in this article are merely the biggest fish in an infinite sea of cyber-crime, where over 100 million new malware programs target consumers and organizations every year.
Mydoom
Estimation of damage value: $38 billion
Mydoom, the worst computer virus epidemic in history, is thought to have cost $38 billion in damages in 2004. This malware, also known as Novarg, is officially a “worm” that spreads through bulk emailing. One time, 25% of all emails sent were affected by the Mydoom virus.
Infected computer addresses were scraped by Mydoom, which then transmitted copies of itself to those addresses. Additionally, it connected those infected systems to a botnet, a network of computers used to launch distributed denial of service (DDoS) attacks. The goal of these attacks was to take down a target server or website.
One percent of all phishing emails are still produced by Mydoom today. Considering the 3.4 billion phishing emails received daily, that is no small accomplishment. According to that number, Mydoom has developed a life of its own and, 16 years after its conception, has infected enough insecure computers to send 1.2 billion copies of itself annually.
Despite a $250,000 reward being announced, the creator of this harmful computer worm evaded capture.
Sobig
Estimation of damage value: $30 billion
The Sobig computer virus from 2003 is actually a worm. In terms of scope, it is only surpassed by the Mydoom virus. The $30 billion sum includes Canada, the United Kingdom, the United States, mainland Europe, and Asia. In fast succession, different versions of the worm made available. The most harmful one being Sobig.F.
This malicious malware was attached to emails as legitimate computer software. It interfered with countless other businesses in addition to disrupting Air Canada’s ticketing. The successful bug’s developer was never found, despite the widespread damage it caused.
Klez
Estimation of damage value: $19.8 billion
On the list of the worst computer viruses ever produced, Klez comes in at a close third. It affected 7 million PCs in 2001, or roughly 7.2 percent of all machines, and caused an estimated $20 billion in damages. The Klez worm, among other things, tried to disable other infections by sending phony emails, impersonating well-known senders, and so on.
Klez was released in a variety of forms, just like other viruses and worms. As it replicated itself and propagated throughout each victim’s network, it infected files. It persisted for many years, getting worse with each iteration.
Since most of the computer viruses on this list first appeared online, Operating system has advanced significantly, and now come with the necessary built-in security to combat this still circulating virus.
ILOVEYOU
Estimation of damage value: $15 billion
The ILOVEYOU virus from 2000 spread by sending a fake “love letter” that appeared to be a secure text file. Similar to Mydoom, this attacker sends copies of itself to each email address in the contact list of the compromised machine. After being released on May 4, it quickly reached more than 10 million PCs.
Onel de Guzman, a college student from the Philippines, invented the virus. He created the virus because he was short on money so that he could log into online sites he wanted to utilize them for free without having to pay. He afterwards claimed that he had no idea how far his creation would go. Another name for this virus is Loveletter.
WannaCry
Estimation of damage value: $4 billion
Ransomware, such as the WannaCry computer virus from 2017, is a threat that seizes control of your computer (or cloud files) and holds them hostage. The WannaCry ransomware destroyed computers in 150 different nations, resulting in significant productivity losses as companies, hospitals, and governmental agencies that refused to pay were forced to start over with their systems.
Around the world, the spyware spread like wildfire through 200,000 computers. When a 22-year-old security researcher in the UK discovered a means to disable it, it came to an end. Computers with outdated operating systems were particularly vulnerable. Because of this, security professionals constantly advise updating your systems periodically.
Zeus
Estimation of damage value: $3 billion
A tool for cyber theft, the Zeus computer malware first appeared online in 2007. Three years later, Unisys released a whitepaper in which it estimated that it was responsible for 44% of all banking malware attacks. By that point, it had compromised 2,500 firms overall, 88% of all Fortune 500 companies, and 76,000 computers across 196 nations.
The Zeus botnet was a collection of programs that coordinated to seize control of computers for a distant “bot master”. It was first used to move money to hidden bank accounts in Eastern Europe. In 2010, more than 100 members of the virus’ criminal network, predominantly in the United States, were detained. Even though the virus is less common now, some of its source code can still be found in more recent botnet malware.
Zeus reportedly caused $100 million in damages. The true cost, however, is unquestionably far higher when considering missed productivity, removal, and unreported theft. With inflation taken into account, a $3 billion forecast would cost $3.7 billion in today’s money.
Code Red
Estimation of damage value: $2.4 billion
The Code Red computer virus, a worm that first surfaced in 2001, infected 975,000 hosts. It ran entirely in the memory of each machine and plastered the message “Hacked by Chinese!” across infected web pages. Most of the time, it left no traces on hard disks or other types of storage.
The estimated financial costs are $2.4 billion. A distributed denial of service (DDoS) attack was launched against the U.S. White House website, www.whitehouse.gov, by the malware, which also targeted websites on infected machines. In order to counter Code Red, the White House actually had to alter its IP address.
Slammer
Estimation of damage value: $1.2 billion
With over 200,000 computer users, the SQL Slammer infection cost an estimated $750 million in 2003. Through the use of vulnerabilities and random IP address selection, this computer virus spread to other machines. It launched a DDoS attack on multiple internet hosts using these victimized PCs, greatly delaying internet traffic.
The Slammer worm particularly targeted banks in the United States and Canada, putting numerous ATMs offline. Customers of the Imperial Bank of Commerce in Toronto discovered they couldn’t get money. In 2016, the attack reappeared and was launched from IP addresses in Ukraine, China, and Mexico.
CryptoLocker
Estimation of damage value: $665 million
Since their 2017 high, ransomware assaults like the 2013 CryptoLocker malware have decreased. This spyware encrypted the files on over 250,000 devices before attacking them. It informed customers that “your essential files encryption produced on this computer” in a red ransom note. The notice was accompanied by a payment window.
The CryptoLocker malware was produced and distributed by its developers using a worm known as the Gameover Zeus botnet. A study by the security company Sophos found that the typical ransomware attack costs a company $133,000 to recover from. If we assume that CryptoLocker affected 5,000 businesses, its direct cost would be $665 million without including all side damages.
Sasser
Estimation of damage value: $500 million
A 17-year-old German computer science student named Sven Jaschan created the Sasser worm. 2004 saw him detained at the age of 18 when a $250,000 bounty was placed on the head of the person who created the computer virus. Authorities received information from a friend of Jaschan that the kid was behind both the harmful Netsky.AC attack and the Sasser worm.
After it was discovered that Jaschan was a minor when he wrote the malware, he was granted a suspended sentence. Although some accounts put the cost of the Sasser worm’s harm at $18 billion, the comparatively low infection rate points to a more realistic cost of $500 million.