What Is a Computer Virus?

There’s a reason why the definition of a computer virus is so similar to that of a biological: it’s persistent, needs a host to latch on to, can replicate, is designed to spread, and is difficult to kill without the right medication. This article will teach you what you can do to protect yourself from an electronic viral infection.

How do viruses work?

Viruses can be programmed to have different purposes, but they all work in the same way. Let’s look into how a virus could even make its way into your personal network.

Viruses, like most malware, are insidious in nature. Hackers typically attach viruses to different files – anything from MP3s, spam email attachments, or games. So any files that you download have the potential of harbouring a virus.

Viruses often lie dormant for some time, waiting for the user to activate them. Once you open the infected file, the virus will be set in motion and attach itself to a program in your network. Then it gets down to work. How a virus works depends on the reason it was created. Some of these reasons may include:

  • Deleting files;

  • Keylogging;

  • Spamming your email contacts list;

  • Replicating itself to the point of severe disruption of your network;

  • Reformatting your hard drive.

Viruses normally have only one purpose. However, as antivirus software advances, so does cybercriminals’ ingenuity. In reaction to increased cybersecurity, they have created the polymorphic virus.

What is a polymorphic virus?

A polymorphic virus virus truly lives up to the name ‘virus’. Like a biological virus, it can mutate, making it much harder to detect and stop. But differently from ‘regular’ viruses with a single purpose, the polymorphic virus was created with a mutation engine that will regularly change the coding of the virus. The coding of the virus is basically it’s DNA, it defines the purpose of it. Recent iterations of this nasty type of malware have shown that it can change up to 3-4 times a minute. A 2018 study by Webroot, cybersecurity specialists, shows that 94% of malware infections are polymorphic in nature.

Can my device get infected?

Travel back in time 20 years, and the idea of your cell phone getting infected with a computer virus would be ludicrous. Flashforward to modern times, where cell phones are basically miniaturized computers we carry around in our pockets, and the once-fanciful threat has become an unfortunate reality.

Your phone can download and open files from the internet just as well as your home computer or laptop. Many of us also have banking or online shopping apps on our portable devices. Once a data-stealing virus has found its way onto your phone or tablet, all those private details can be logged and stored for a hacker to exploit.

What are some examples of a computer virus?

Polymorphic virus. This is the most common type of virus found in modern attacks. It mutates to cause as much chaos and disruption as possible and is very difficult to detect.

Direct action. Also quite a common virus, and one of the easiest to detect. It targets .exe files, replicates itself, and makes it impossible to run the file it’s attached to. Fortunately, it’s very easy to purge with antivirus software.

Resident virus. This type is similar to the direct action, but instead of waiting until you click on an .exe file to be activated, it will install itself onto your computer or device straight away. These viruses hide in your RAM and disrupt your computer processes.

Browser hijacker. This virus can redirect your browser homepage to malicious sites, or just force advertisements on you.

Macro virus. This is a virus that mimics legitimate programs, like MS Word or Excel. If you click on the dummy file, you’ll be redirected to a malicious or, more likely, pornographic website.

How can I tell if I have a virus?

The symptoms of a virus are quite easy to detect once you know what to look for. These may be:

  • Slowed processes;

  • Unexplained bandwidth usage;

  • Your device or computer frequently crashing;

  • Pop-up advertisements;

  • Changed passwords.

If you’ve noticed any of the above, it’s time to activate your antivirus suite immediately.

How do I prevent a virus infection?

The best way to prevent any computer virus attacks is educating yourself. Learn how to recognize the signs of an infection and what to stay away from online. Here are some handy tips you might want to memorize:

  1. Keep your computer updated. Many viruses can find loopholes in older software. Software updates regularly patch any security vulnerabilities that may have been found in older versions.

  2. Think twice before opening a link. Whether it’s a free game download or a suspicious link sent to your email, don’t click on it. Cybercriminals rely on their victims’ lack of common sense. If you ever receive an unwanted email promoting something that seems too good to be true, send it straight to the trash folder.

  3. Use a behaviour-based antivirus. This form of cybersecurity analyzes any potential malicious entities based on how they act, rather than on the type of coding they have. This is the best way to deal with polymorphic viruses.

If you follow these tips, you’ll have less chances of becoming a victim of a cybercrime.

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Chad Hammond
Verified author
Chad loves traveling and technology. His global view and open-mindedness add interesting angles to various security topics. He has already traveled to over 80 countries and is not planning to stop any time soon.
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