What are Computer Viruses?

Introduction to viruses. Norton defines a computer virus as this, “A computer virus is much like a flu virus. It is designed to spread from host to host and has the ability to replicate itself.” So there’s a lot of different types of viruses out there, and they typically have these types of payloads. They’re designed to spread through your network, steal your information, install a backdoor, meaning a connection from an outside person onto your computer network, destroy your files, or lock you out of your computer network or files. So there’s different types of viruses out there. These are the typical ones you’ll see out in the wild or hear about. There’s ransomware and cryptoware.

Ransomware will typically hold your files hostage, while cryptoware may encrypt all your files, with or without a ransom. We have Trojans. A Trojan will disguise itself as another piece of software, while containing a virus payload. And this is typically represented as a legitimate piece of software. Say you find a game online. You download it. It’s a paid program, but you find it for free. Typically, things like that will have a Trojan, meaning you download the game, you install it. It may even run. But inside that code contains a virus that infects your computer and network. We also have malware. Malware is a malicious software that can have various payloads. We have a polymorphic virus.

Polymorphic viruses are pretty sophisticated, and typically we see this with state-sponsored-type viruses. Polymorphic viruses will change their signature, meaning it will change itself in order to avoid detection. There’s worms. Worms are a typical type of virus that will spread through your network. It is designed to replicate itself and spread throughout the network and computer system. We also have scareware. Scareware is oftentimes represented as a fake antivirus that’s going to pop up, telling you that you need to buy this antivirus or call this number. Or it could be a warning that pops up, such as a FBI warning, police, your ISP saying, “Hey, we caught you doing something bad. You need to call this number or send us money.”

These are all typically types of scareware. It typically scares us in order to take action that might not be in our best interests. So wrapping up, ways to keep yourself safe. Keep your antivirus updated. Be sure your antivirus is up to date at all times and running. Be careful where you download files from. Always download from safe sites. Beware of strange attachments and drives. Don’t open links, open attachments from unsolicited emails. And, also, if you find a disc or, more often, a USB drive that you don’t recognise, don’t plug it in. Any of these things can contain malicious payloads. So in the next video, we’ll be talking about understanding computers and how they can become infected. Thank you for watching.

I’ll see you in the next video.