Computers viruses, worms, ransomware, etc. are kinds of malicious software that no user should take lightly. On several occasions, we have touched upon security steps that each user should take in order to protect its identity and data. Sadly sometimes even when all precautions are taken some malware can still slip through and wreak havoc. Today we are looking at some of the worst or the best, depending on your view that has indeed wreaked plenty of havoc.
10 worst computer viruses in historyIn the list of the 10 most famous computer viruses below, we show the costs, dates, reach, and other key facts. First a note about terms: we use the words “virus” and “worm” interchangeably because most readers search for them that way. But there’s a subtle difference that we explain after the list.
The worst computer virus outbreak in history, Mydoom caused estimated damage of $38 billion in 2004, but its inflation-adjusted cost is actually $52.2 billion. Also known as Novarg, this malware is technically a “worm,” spread by mass emailing. At one point, the Mydoom virus was responsible for 25% of all emails sent.
Mydoom scraped addresses from infected machines, then sent copies of itself to those addresses. It also roped those infected machines into a web of computers called a botnet that performed distributed denial of service (DDoS) attacks. These attacks were intended to shut down a target website or server.
Mydoom is still around today, generating 1% of all phishing emails. That’s no small feat considering the 3.4 billion phishing emails sent each day. By that figure, Mydoom has taken on a life of its own, infecting enough poorly-protected machines to send 1.2 billion copies of itself per year, 16 years after its creation.
Though a $250,000 reward was offered, the developer of this dangerous computer worm was never caught.
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The 2003 Sobig computer virus is actually another worm. It is second only to the Mydoom virus in its scope. The $30 billion figure is a worldwide total, including Canada, the U.K., the U.S., mainland Europe, and Asia. Several versions of the worm were released in quick succession, named Sobig.A through Sobig.F, with Sobig.F being the most damaging.
This cybercriminal program masqueraded as legitimate computer software attached to emails. It disrupted ticketing at Air Canada and interfered with countless other businesses. Despite its widespread damage, the creator of the successful bug was never caught.
Klez is a close third on the list of the worst computer viruses ever created. With nearly $20 billion in estimated damages, it infected about 7.2% of all computers in 2001, or 7 million PCs. The Klez worm sent fake emails, spoofed recognized senders and, among other things, attempted to deactivate other viruses.
As with other viruses and worms, Klez was released in several variants. It infected files, copied itself, and spread throughout each victim’s network. It hung around for years, with each version more destructive than the last.
Windows has come a long way since most of the computer viruses on this list hit the web. Thankfully, built-in protection with Microsoft Defender is always on the watch.
The year 2000’s ILOVEYOU virus worked by sending a bogus “love letter” that looked like a harmless text file. Like Mydoom, this attacker sent copies of itself to every email address in the infected machine’s contact list. Shortly after its May 4 release, it had spread to more than 10 million PCs.
The virus was created by a college student in the Philippines named Onel de Guzman. Lacking funds, he wrote the virus to steal passwords so he could log into online services he wanted to use for free. He reportedly had no idea how far his creation would spread. This virus is also known as Loveletter.
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The 2017 WannaCry computer virus is ransomware, a virus that takes over your computer (or cloud files) and holds them hostage. The WannaCry ransomware ripped through computers in 150 countries, causing massive productivity losses as businesses, hospitals, and government organizations that didn’t pay were forced to rebuild systems from scratch.
The malware raged like wildfire through 200,000 computers worldwide. It stopped when a 22-year-old security researcher in the U.K. found a way to turn it off. Computers with out-of-date operating systems were hit especially hard. That’s why security experts always recommend updating your systems frequently.
In September 2020, one of the potentially largest computer virus attacks in medical history hit Universal Health Services. The U.S. hospital chain, which has more than 400 locations, was reportedly struck by damaging ransomware. The attack forced the cancellation of surgeries and made healthcare workers switch to paper records.
The Zeus computer virus is an online theft tool that hit the web in 2007. A whitepaper by Unisys three years later estimated that it was behind 44% of all banking malware attacks. By then, it had breached 88% of all Fortune 500 companies, 2,500 organizations total, and 76,000 computers in 196 countries.
The Zeus botnet was a group of programs that worked together to take over machines for a remote “bot master.” It originated in Eastern Europe and was used to transfer money to secret bank accounts. More than 100 members of the crime ring behind the virus, mostly in the U.S., were arrested in 2010. It’s not as prominent today, but some of the virus’ source code lives on in newer botnet viruses and worms.
Zeus caused documented damage of $100 million. But the real cost in terms of lost productivity, removal, and undocumented theft is undoubtedly much higher. A $3 billion estimate, adjusted for inflation, puts this virus at a cost of $3.7 billion in today’s dollars.
First observed in 2001, the Code Red computer virus was yet another worm that penetrated 975,000 hosts. It displayed the words “Hacked by Chinese!” across infected web pages, and it ran entirely in each machine’s memory. In most cases it left no trace in hard drives or other storage.
Financial costs are pegged at $2.4 billion. The virus attacked websites of infected computers and delivered a distributed denial of service (DDoS) attack on the U.S. White House’s website, www.whitehouse.gov. In fact, the White House had to change its IP address to defend against Cod Red.
Can your printer get a virus? See our cool infographic: The State of Printer Security
The SQL Slammer worm cost an estimated $750 million across 200,000 computer users in 2003. This computer virus randomly selected IP addresses, exploiting vulnerabilities and sending itself on to other machines. It used these victim machines to launch a DDoS attack on several internet hosts, significantly slowing internet traffic.
The Slammer worm hit banks in the U.S. and Canada especially hard, taking ATMs offline in many locations. Customers of Toronto’s Imperial Bank of Commerce found themselves unable to access funds. The attack reared its ugly head again in 2016, launching from IP addresses in Ukraine, China, and Mexico.
Thankfully, ransomware attacks like the 2013 CryptoLocker virus have dipped since their 2017 peak. This malware attacked upwards of 250,000 machines by encrypting their files. It displayed a red ransom note informing users that “your important files encryption produced on this computer.” A payment window accompanied the note.
The virus’ creators used a worm called the Gameover Zeus botnet to make and send copies of the CryptoLocker virus. According to a report by security firm Sophos, the average ransomware attack costs a business $133,000. If we estimate that CryptoLocker hit 5,000 companies, that would put its total cost at $665 million.
Where will cybersecurity go next? See our guide: The Future of Cybersecurity
The Sasser worm was written by a 17-year-old German computer science student named Sven Jaschan. He was arrested at the age of 18 in 2004 after a $250,000 bounty was posted for the computer virus’ creator. A friend of Jaschan’s tipped authorities that the youth had penned not only the Sasser worm but also the damaging Netsky.AC attack.
Jaschan was given a suspended sentence after it was found he was a minor when he wrote the malware. The Sasser worm crashed millions of PCs, and though some reports put damages at $18 billion, the relatively low infection rate suggests a more likely cost of $500 million.
Other notable viruses
The top 10 worst computer viruses above are just the ugly tip of a gargantuan digital iceberg. With a million new malware programs popping up every 3 years, we may miss the forest for a few outstanding trees. Here are just a few more viruses that have wreaked havoc over the years:
Mimail: This worm tried to harvest data from infected machines to launch a string of DDoS attacks, but was relatively easy to remove.
Yaha: Yet another worm with several variants, thought to be the result of a cyber-war between Pakistan and India.
Swen: Written in C++, the Swen computer worm disguised itself to look like a 2003 OS update. Its financial cost has been pegged at $10.4 billion, but not reliably.
Storm Worm: This worm showed up in 2007 and attacked millions of computers with an email about approaching bad weather.
Tanatos/Bugbear: A 2002 keylogger virus that targeted financial institutions and spread to 150 countries.
Sircam: A computer worm from 2001 that used counterfeit emails with the subject line, “I send you this file in order to have your advice.”
Explorezip: This worm used fake emails to spread to every machine on thousands of local networks.
Melissa: The most dangerous computer virus in 1999, Melissa sent copies of itself that looked like NSFW pics. The U.S. FBI estimated cleanup and repair costs at $80 million.
Flashback: A Mac-only virus, Flashback infected over 600,000 Macs in 2012 and even infected Apple’s home base in Cupertino, Calif. In 2020, there’s now more malware on Macs than on PCs.
Conficker: This 2009 virus still infects many legacy systems and could do significant damage if it ever activates.
Stuxnet: This worm is reported to have destroyed Iranian nuclear centrifuges by sending damaging instructions.
Moving icons in TaskbarError 1309. Error reading from file: pathfilename.cab. Verify that the file exists and that you can access it.When installing Microsoft Office 2003, the error message may appear in the following format: Fatal Error During Installation
Error CausesIt is a device driver error that users encounter when they use Windows 2000 operating system and its later versions.
The error occurs when the connected peripheral device, upon removal using the ‘Safe Removal Hardware’ program, hangs up a problem within the process. The error prompt you then see is referred to within the operating system as error code 47.
It usually pops up on your computer screen with the following message:
Windows cannot use this hardware device because it has been prepared for "safe removal", but it has not been removed from the computer. (Code 47)
Error CausesThere are many factors responsible for the Error Code, the primary ones are listed below:
Error Code 47, like other device driver error codes, is relatively easy to solve. You can fix the error code in the following ways:
Unplugging and plugging the USB cable of the device into the computer is the easiest way to resolve the error.
Doing this will help refresh the system and increase the likelihood of the device driver files loading and function properly.
Another simple method you can use to solve your PC error code is to simply restart your Windows system.
It may be that the error prompted upon connecting the device you have connected is merely a temporary problem, and upon restart, will resume functioning smoothly.
If both of the above-listed methods fail to resolve the problem, you may have to resort to manually uninstalling and then reinstalling the device driver causing the problem.
This would be necessary since the remaining incomplete files due to a partial removal or installation of programs is what contributes to the error code. By uninstall and reinstalling the device driver program, it would lead to the completion of the files.
You can do this by firstly logging in as Administrator and open Device Manager. Select the device that is causing the problem and double click it and make sure that the peripheral is connected properly to the PC.
Upon opening, click on the ‘Driver’ tab and then select ‘Update Driver’. Make sure to refer to the system documentation that you received with your PC or computer to check for the motherboard details and driver specifics.
Manually uninstalling and reinstalling the driver will usually do the trick; however, it may be time-consuming especially when you would have to resort to your hardware user manual.
Therefore, using a program such as DriverFIX can save you a lot of time and frustration in having your device work properly on your computer.
DriverFIX, with its user-friendly approach to help you fix your PC issues, comes with an integrated database that detects which drivers you need to reconfigure within just a few seconds and downloads it automatically. It further ensures that your drivers are installed in their entirety leaving no room for any incomplete files to remain that create Error Code 47. It also has the added advantage of being able to backup and restores your files should there be the slightest possibility of system file damage. Thus, registry damage can be averted by letting the software roll back the system files to an earlier healthy checkpoint. DriverFIX is the answer to fixing your PC error codes accurately and quickly. Click here to download DriverFIX to fix Error Code 47 quickly and effectively!“Windows is unable to reach your company’s activation service. Please connect to your corporate network. If you are connected and continue to see the error, contact your system administrator. You can also click on the error detail to find the exact error. Error code: 0xC004F074.” “Activating Windows(R), (Key hash)… Error: 0xC004F074 The Software Licensing Service reported that the computer could not be activated. No Key Management Service (KMS) could be contacted. Please see the Application Event Log for additional information.” “Error 0xC004F074, SL_E_AUTHN_MISMATCHED_KEY, The Software Licensing Service reported that the key is mismatched.”To fix the Windows 10 Activation error 0xC004F078, you have to use the correct key for your type of Windows copy or use Command Prompt to reinstall the key or you could also try running the Activation troubleshooter.
Error code 0xc00007b usually manifests itself via the inability to start an application properly. It can occur when users attempt to run a game or other programs on their computer. In such a case, the application will not start and a message box will pop up stating that error code 0xc00007b has occurred. The error code is likely to occur when users attempt to run a program in the incorrect or inappropriate bit. For instance, if you try to load a 32bit location with a 64bit location.
Error CausesError code 0xc00007b affects various versions of the Windows operating system, including Windows 7, 8, 8.1, and Windows 10. In the case of error code 0xc00007b for Windows 10, the error may be caused by issues related to software you’ve installed on your machine. This may cause software conflict resulting in the need to install programs like DirectX. Left unchecked, error code 0xc00007b could incite other error codes in Windows 10, such as error code 0xc004f034.
To repair error code 0xc00007b for Windows 10 devices, users will need to implement at least one manual repair procedure. Manual repair methods are effective in combating these issues as they can address the issues causing the error in the first place, thus fixing the problem.
The manual repair procedures for fixing error code 0xc00007b are very straightforward and can be implemented with little technical knowledge. However, you may need to contact a Windows repair technician if you have difficulty fixing the error code after completing the manual repair methods listed below.
Microsoft DirectX is an application usually included in the Microsoft operating system. It enables users to access high-speed gaming and multimedia on their PC. The latest version of this Windows technology is available on Microsoft’s official site.
Visit the Microsoft website and search for DirectX End-User Runtime Web Installer. Once you have located the latest version of the program, select the preferred language you would like DirectX to run in, and then click download. Run the program, then be sure to reboot your computer.
Note that this solution should only be applied if you are having issues running or displaying a gaming or multimedia application. Once you’ve correctly installed the latest version of DirectX, it should be able to fix underlying issues that may be causing error code 0xc00007b to occur. If you are still unable to run applications after completing this manual repair procedure, however, you will need to apply another method to fix error code 0xc00007b for Windows 10.
.NET Framework, a framework developed by Microsoft, provides solutions for users who may be having problems with applications. To download the latest version of the .NET framework, follow the steps listed below.
To ensure you successfully download the latest version of the .NET Framework, verify your computer is properly connected to the Internet while downloading the software. Also, follow the instructions provided on the Microsoft website.
After completing the download process, reboot your computer then check if you have successfully resolved error code 0xc00007b for Windows 10. If this manual repair method is successful, you will be able to access your gaming and multimedia programs. Otherwise, the error code message box will reoccur, stating that the application error code is present on your device. Apply the next manual repair procedure to correct the error code if this reoccurs.
In certain instances, application error codes like error code 0xc00007b affect PC users who fail to install the most current Windows updates on their device. That is why it’s important to check your system and ensure you have installed all the latest updates.
The updates, if any are available, will automatically be installed on your PC once you access Windows Update in Settings. Reboot your computer then check if you are able to run programs that previously would not open due to error code 0xc00007b. If problems persist resulting in the reoccurrence of the error code, reinstall the applications you are unable to open or get help from a Windows repair technician.
If you wish to always have at your disposal a utility tool to fix these Windows 8 and other related issues when they do arise, download and install a powerful automated tool.
Email Access Online is a browser extension published by Polarity Technologies Ltd. That offers users quick and easy access to emails and weather reports. While this might sound interesting and useful, there is nothing this extension offers that cannot be solved with a few simple bookmarks.
While installed Email Access Online monitors the user's browser activity and records visited websites, clicked links, and bought products, this data is later used to serve partner ads if the user looks for the covered categories, additionally, it will hijack your new tab page, changing your search engine to Yahoo to allow easier ad placement.
Browsing the internet with this extension enabled will result in additional ad placement, pop-up ads, and sponsored links throughout your browsing sessions.
Upon further investigation, it was discovered that this extension is a repack of MyEmailXP, which was a repack of Fast Email Checker. Due to its suspicious delivery methods and information gathering, several anti-virus scanners have marked this extension as a browser hijacker and it is recommended to remove it from your computer.
5 Essential IT skills everybody should know“This policy setting prevents File Explorer from encrypting files that are moved to an encrypted folder. If you enable this policy setting, File Explorer will not automatically encrypt files that are moved to an encrypted folder. If you disable or do not configure this policy setting, File Explorer automatically encrypts files that are moved to an encrypted folder. This setting applies only to files moved within a volume. When files are moved to other volumes, or if you create a new file in an encrypted folder, File Explorer encrypts those files automatically.”
Error CausesError Causes