The Most Common Windows Malware StaffOct. 21, 2018
Malware on your computer
Malicious software, or malware, is a catch-all term for any kind of software that enters into your computer and wreaks havoc on your Windows operating system. This could be in the form of a virus, adware, ransomware, Trojans or worms.

Types of Malware

We break down the most common types of Windows malware as well the best antivirus for Windows to help protect from contracting malware in the future.


Shadyware is simply defined as unwanted advertisements. Shadyware doesn’t directly damage your PC like a virus, but that doesn’t mean it’s any less dangerous. Also known as “potentially undesirable programs” (or PUP), some of these can do considerable damage to your Windows operating system.


Spyware software attempts to collect personal and covert information about someone without them knowing. It snoops while you work on your device, capturing information on anything from your online activity to sensitive data like financial details or passwords and transmits this back to third parties that want your information. Windows 10 has built-in spyware, and despite a web-based privacy dashboard, data collection can still occur.


Keyloggers work by recording which buttons you press, usually in an app, and then leaking that data to third parties – which could lead to identity theft or other, potentially very expensive, breaches further down the path. Both keyloggers and shadyware tend to work quietly and are getting increasingly sophisticated - meaning you might not know you’re hit until it’s too late.


Finally there’s Adware, which floods your device with unwanted ads and pushes you to download “free” software. This typically contains vulnerabilities that make you more open to attack, but even when it doesn’t totally up-end your life, all those flashing ads are still a major pain in the neck. Furthermore, adware can download unwanted files and programs to your browser. 


Another nasty little troll that has gained ground in recent years is the Trojan Horse. As the name suggests, these present themselves as harmless presents - until you let it through the gates. Once inside, all the nasty elements hidden beneath the surface jump out to take your device down from the inside.

Trojans often come in the form of an optional add-on that comes with a game, software download, browser extension or so on. If you don’t recognize what it is and it’s extra to the software you actually want, it’s likely a trojan. 


Crimeware, or ransomware, is the last virus you ever want to get into your PC. It works by taking certain files hostage and threatening to destroy them unless you pay the cybercriminals that infected you the amount of money they demand.

Not only that, ransomware hackers have learned that they can spread the malice and reap the financial rewards even faster by offering you discount on the ransom demand if you forward the malicious code to a set number of other people, who then become infected. It’s also one of the main reasons this form of malware has spread so fast in recent years, and Windows operating systems are especially vulnerable.

Viruses and Worms

These tricky little eels of the malware scene keep getting smarter all the time, finding new ways to slip into your device, corrupt your files, mess with your programs, and slow your computer.

Typically, viruses work by infecting one program and then, once you install and run it, spread to other programs installed on the same device. The real headache starts when viruses embark on a spree of deleting critical files across your operating system, and swim across into other shared files and databases on the network, too.

Worms are basically the same as viruses, except that they don’t need an initial program to stick to in order to burrow their way in. They’re standalone programs that weave through the network, trashing everything in their path.

How to Stay Safe

Having a reputable, powerful antivirus system in place to counter these threats is essential – as is keeping your antivirus up to date to tackle the newest nasties before they exploit a chink in the armor. Run full scans on a regular basis and keep your real-time scanning on too, just in case.

But it also makes sense to stay vigilant about what you let into your device in the first place. Never download an attachment that seems dodgy or you’re not expecting, don’t opt for free trials of programs unless you’re 100% sure they’re safe, always make sure you’ve unchecked any boxes for additional programs or browser bars before you click to download and install a new piece of software, and of course, choose a top antivirus software. Stick to these principles, and you’re likely to improve your protection.