What is malware?

Here’s everything you need to know about what malware is and how to prevent it.

Everything you need to know about what is a malware_alt

Malware definition

The definition of malware comes from combining two words: malicious + software = malware. Malware is software designed to work against the interests of the owner of a system or device. Some types can find their own way into your device, while others need to be planted there.

What does malware do? Its effects vary in severity, from tracking relatively harmless data to holding your device at ransom or destroying it for fun.

Types of malware and malware attacks

You’ll find malware types of every sort below. There are countless varieties out there, so we’ll stick to some of the most widespread malware examples. Here are the top most common types of malware:

Adware

Adware is a relatively innocuous type of malicious software that focuses on making money rather than harming your computer. This aggressive advertising-supported software displays banner advertisements on websites and application windows.

Symptoms may vary, but the main one will be pop-up ads. They may show up on your desktop or in programs, websites, or apps that didn’t have them before.

Spyware

Spyware is made to (surprise!) spy on you. This malware hides in the background, monitoring your computer usage and internet browsing activity. It can harvest passwords, banking details, and emails and even perform keystroke logging or change security settings. All of the information it gathers is sent to a remote user. It can also download and install other malicious applications without your permission.

Virus

Much like a biological virus, a computer virus will spread from host to host to infect as many devices as possible. Attached to files or programs, it can be spread through downloads, email, social media, or text messages.

However, a virus usually cannot infect a computer autonomously – it needs a user to run the program it is attached to. The harm caused by viruses ranges from minor annoyances like desktop wallpaper alterations to major system crashes or complete loss of data.

Worm

In comparison to viruses, worms can seem quite innocent, as they do not cause any direct damage to a system. A worm’s entire purpose is to copy itself and spread across a local drive or network.

Worms can also be paired with “payloads” designed to damage a system or extract information, but they don’t have to. The first worm, Creeper, simply notified infected users of its presence.

Trojan

Trojan malware infiltrates computers by hiding in innocent-looking programs, like the Trojan horse of the Greek legend. Once it’s in, it can create backdoors for hackers to get into your system and collect your data or even completely lock you out of your computer. For example, the Zeus trojan collects data like victims’ keystrokes and credentials. Emotet was notorious for stealing data from individuals and companies alike.

Ransomware

Ransomware is one of the most serious cyber threats due to its ability to spread quickly and cause costly damage. Ransomware is designed to make a profit. Once the malware infects a machine through a system vulnerability, it encrypts all data, locking the user out. Then, it asks the victim to pay a ransom to decrypt the files.

Keylogger

Keylogging is the process of tracking the keys a user types to discover their sensitive passwords or monitor private communications. Different types of keyloggers exist, including ones based on stalkerware or hardware. This can make them very hard to discover as well.

How malware spreads

Malware could infect your devices in several different ways. Here are a few of the most common ones:

The most popular method of spreading viruses is through email. Both simple spam and sophisticated phishing attacks still trick people into clicking on links or downloading attachments that contain malware.

Careless browsing

If you click on any pop-up or advert that you come across while browsing, chances are, you’ll eventually end up on a malicious website. It will download malware in the background, and just like that, you’ll have a keylogger or a trojan on your device.

Coworkers

Some malware spreads from one device to another through the internal network. For example, someone in the office forgot their cybersecurity training and clicked on a malicious link. So the next day, everyone’s computers are infected, and all their files are encrypted, with no access to their accounts.

Bundled software

Malware is known for piggybacking. So even when you download a trustworthy piece of software, you might end up with more than you asked for. You can install malware together with legitimate software without even noticing, and it could be anything from slightly annoying adware to spyware stealing your banking data.

Signs of malware

Changes in speed

Your device or browsers have slowed to a crawl

Performance issues

Your device frequently freezes or crashes

Apps acting weird

Programs on your computer open or close without warning

Suspicious apps

Files, add-ons, or apps on your device that you don’t recognize

Setting changes

Your security, browser, or app settings change without your consent

Unusual messages

Unusual emails or texts that were sent without your permission

Overheating

Your device overheats, or its battery drains super fast

Suspicious charges

Your phone bill has increased without you knowing why

How to prevent malware?

Here’s how you prevent a malware attack:

Woman using ultimate antimalware security software_alt

Staying safe by being aware of malware threats_alt

Research and read reviews to avoid possible malware threats_alt

Use antimalware security software
One of the most comprehensive defenses against any malicious code is a piece of reputable security software. As always, premium tools are the way to go. The best software packages are backed by dedicated teams of developers who monitor the latest threats and respond to them with updates as quickly as possible.
Become a vigilant Internet user
Don’t ever click on pop-ups, and make sure you’re clicking on the right “X” to close them. To make things easier, switch on NordVPN’s Threat Protection feature, and it will block ads for you. Mouse-over or right-click on links before clicking on them to see where they take you.
Back up your files
Maintaining frequent backups of your files may not prevent you from getting malware, but it will make attacks much easier and less damaging to deal with. Device resets are a nearly guaranteed way to wipe out most malware, but they’re very hard to do if every wipe means losing important files. With frequent, secure backups, that won’t be a problem.
Do your homework
Before downloading an app, read some reviews online – and be sure to find at least one negative one as well. What do they say? Are users complaining about features or performance, or are there more serious issues at play? Has anyone accused the app of being malware?

Research the most serious vulnerabilities facing your device or operating system. If you know them, you can avoid them.

Protecting devices with strong passwords_alt

Keep your software up to date
When a trusted app or your OS asks you to confirm an update, you probably should. In addition to providing feature and performance improvements, updates usually patch up newly discovered security vulnerabilities.
Change your passwords and keep them secure
Learn how to craft a strong password that you’ll remember. You can also use a password manager like NordPass so that you don’t need to rely on weak passwords – it’ll generate, remember them and secure them for you.

When you discover malware on your device and eliminate it, one of the first things you’ll want to do is change your passwords.
Learn your devices inside and out
Whether it’s a smartphone or a PC, your device has plenty of built-in settings that can go a long way to make it more secure.

You can use the NordVPN app on smartphones, laptops, PCs, and routers, enjoying better protection from malware across all your devices, especially with the Threat Protection feature.

Protect your digital life with more cybersecurity apps

Enjoy the all-round security provided by our apps. Protect your internet traffic, passwords, and files.

How does NordVPN help?

How NordVPN can help depends on the malware you’re up against.

Blocks dangerous websites

NordVPN’s built-in Threat Protection feature blocks access to malicious websites before they have a chance to trick you into infecting your device.

Deletes malicious files

Threat Protection scans the files you download and, if malware is detected, instantly deletes it.

Fends off pop-ups

Threat Protection blocks potentially malicious ads before you even get the chance to see them.

Secures traffic

The encryption a VPN provides will close off numerous avenues of infiltration for potential hackers and their malware (but not all of them).

Enjoy robust cybersecurity with NordVPN

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Frequently asked questions

What is a malware attack?

A malware attack is a type of cyberattack against a device. A malware attack uses malware to perform unauthorized, malicious actions against the interest of the device’s owner.

Which devices can be affected by malware virus?

Unfortunately, almost every device you own can be affected by malware. If it has an internet connection, it’s probably vulnerable to malware attacks. That includes your laptop, PC, phone, tablet, and even IoT devices.

How can I check a computer for malware?

The most accurate way to find out if your device has been compromised is to scan it for malware using antimalware software. Just make sure your antivirus is secure and trustworthy. Otherwise, you might do more damage than good.

Alternatively, you can take your computer to a professional to help you remove malware.

How can I tell if my Android device has malware?

The most common signs of Android malware include overheating, lagging, glitching, switching off at random, and battery draining fast. Another telltale sign of malware is suspicious apps on your phone. If you see something you don’t recognize on your device, it’s likely malicious software.

How can I tell if my iPhone or iPad has malware?

The signs of malware on your iPhone or iPad are similar to those of Androids. If you notice your device acting weird, its battery drains fast, or it’s glitchy, it can be malware. If you notice apps or files you don’t recognize, these might be malicious software.

How do I get rid of malware?

To make sure that malware is removed before it does any damage, use NordVPN’s Threat Protection. However, if you think that your device is already infected, investing in robust and trustworthy antimalware software is the best course of action. Make sure you do your research before downloading anything on your device. Otherwise, you may make things worse.