What Is Malware? Identify and Prevent Attacks

The threat of malware seems ever-present for Internet users. Whether it's due to a suspicious website, someone knowing your public IP address, a shady email link, or even a computer on your network spreading an infection, malware attacks can happen anywhere. But what is a malware attack and how can you protect against one? It's crucial to know how malware works and how it can appear in order to safeguard your devices and your information as best as possible.

What is malware?

Malware is short for "malicious software." As the name implies, it's any kind of program that seeks to harm a system or individual through technological means. These programs seek to invade or take over a device's operations in order to stop normal functions, cause corruption, steal information, and more.

Depending on the type of malware, it can spy on your computers or mobile devices, take your data or files hostage, delete your data, or slow down the device. It doesn't affect a device physically, but it can destroy your device technically, rendering it unusable.

Malware often installs without the user’s knowledge and can make unwanted or unknown changes to the device’s settings. Malware comes in so many forms that it’s sometimes hard to prevent and detect, even if you know what you’re looking for.

A phone with malware on it

How do I get malware?

Malware gets onto your device through malicious or hacked websites, emails, and downloads, among other things. You could potentially get a malware infection through:

  • clicking a download or website link sent to you via email
  • downloading free content from a suspicious website
  • clicking links in pop-up ads or notifications on a website
  • clicking on website ads
  • downloading free files like illegal music files, movies, or television shows
  • transferring files from USBs or other untrusted devices

Because many of these actions can seem legitimate or safe, it’s sometimes hard to avoid malware. Therefore, it’s crucial to protect your device against attacks as best as you can with software and smart choices.

How to protect against malware

There are several programs that you may use to find spyware, adware, and other types of malware on your system.  However, like a computer virus, it's much better to prevent malware than to clean it from your system. The following is a list of tips to help you prevent your system from falling victim to malware attacks and losing sensitive data.

  • Read the terms of use policy before agreeing to downloads. Before installing shareware or freeware programs, make sure you read and understand the terms of service. The terms should warn users of any software that contains adware.
  • Keep your operating system up-to-date. Setting up automatic updates helps users stay on top of their malware protection. Don't forget to also update your operating system and other software regularly. Software and system updates usually contain security patches to better protect your device from being hacked.
  • Be careful where you browse and try to stay away from suspicious sites. Similarly, be careful where you download files and only install software from reputable companies and sites.
  • Set up a firewall. In your browser and on your network, configure the browser security settings for maximum protection and security.
  • Consider what you plug your device into. Plugging your phone into an unfamiliar computer can result in a malware infection. Juice jacking attacks, for example, can occur if you charge your phone using unprotected public charging ports.
  • Avoid free WiFi if you can. It’s easier for hackers to gain access to your device on it than on a private network. If you can't avoid free WiFi, consider using a VPN to protect your connection and encrypt your network traffic.
  • Think before you click. If an email prompts you to open an email attachment or click a website, contact whoever sent you the email and ask them what it is first. Hackers often disguise malicious links in deceptively normal emails.

Making smart choices online – and bolstering your antivirus software and network protection – helps to lessen your chances at encountering and accidentally downloading malware.

Types of malware attacks


Computer viruses, just like real-life viruses, spread easily. They invade your device and infect a program or file. Then, they travel from device to device, using shared networks, files, and documents as highways. They can even transfer via hardware like juice jacking attacks, which use infected USB ports to transfer malware.

Viruses can corrupt files and even cause whole systems to crash. Once they’ve infected your computer, they have extensive access to what’s kept on your device. For example, a virus might have been designed to collect the personal information held in your files.

Viruses are difficult to eliminate as they infect multiple files on a computer. You can delete an infected file without getting rid of the virus, as it may have already infected many other files on your device. Because of how tricky viruses are, proactively getting strong antivirus software is crucial to protecting your device and your files. 


A computer worm is like a virus on steroids. Viruses require some sort of user action, whether it be downloading a file or opening an email. Worms, on the other hand, don’t need user action to begin an infection. Worms can infect files and systems completely independently; they let the files and programs spread the malware themselves.

Therefore, a single action by one user, such as downloading an attachment, can cause a super-spreading event. That leads to compromised whole networks or systems in a matter of minutes.

Trojan horses

A Trojan horse virus, also known simply as a Trojan, is a type of malware that infects your device by tricking you into downloading something. Named for the Trojan horse of the Trojan war, they present themselves in the same hidden way that the people of Greece did during the actual historical event. Trojans appear to be legitimate even though they're a front for a virus.

For example, a Trojan might appear as an email instructing a user to update his or her antivirus software. If the user clicks the download button, their system will become infected, not healed. Trojans can steal information you provide online, including your passwords and credit card information.


Ransomware attacks encrypt all of the files on a system or network, then demand a ransom to "open" to files again. This is typically done against large organizations, such as city or state governments.  Hackers ensure retrieval of the ransom by threatening to permanently delete all the files if the ransom is not received.

Ransomware infections are one of the costliest forms of malware. This is because organizations typically cannot afford not to pay the ransom. The files can be crucial for the proper functioning of the organization. Also, paying the ransom does not ensure that the files will be unencrypted; hackers may decide to delete the files anyway.


Spyware is a type of malware that allows hackers to see what you're doing on your device or system. This makes it quite easy for hackers to steal your personal information, such as passwords, credit card information, and intellectual property. Essentially, spyware is used to spy on your browsing activities, such as the websites you visit and when you visit them.

Keyloggers are a form of spyware; this type of spyware works by logging each keystroke you type into your computer, giving hackers access to everything from your emails to your passwords to your Google searches. Stalkerware is another subcategory of spyware in which bad actors monitor users without their knowledge or consent.

Spyware infection can change your Windows registry, which causes systems to slow down and creates errors, among other problems. Spyware programs can also take up memory space, and because computers have a very restricted amount of secondary storage memory, this can delay a system. It also bogs down a system's CPU by taking processing time. It’s difficult to remove spyware because the victim is often unaware of its presence entirely.


Adware is a type of malware that sends unwanted advertisements to you in your browser and on your home screen. It’s aggressive, barraging the user with advertisements that they can’t avoid. Many of these advertisements are also scams, which leads to further malware infections if the user accidentally clicks on them or believes them to be real.

Adware usually attaches itself to another program in order to get access to your computer. Once it’s present, it uses browser history to curate targeted ads to display to the victim.

Fileless malware

Fileless malware operates from a computer’s memory, not its hard drive. Therefore, it’s harder to detect, since it can’t be scanned from files. This type of malware uses legitimate programs to compromise your computer; it doesn’t come from suspicious or faulty software like other types of malware.

Signs of malware

Several signs may indicate malware installation on your computer. This isn’t a comprehensive list of malware indicators, but regardless, they're good indicators of a problem. Be wary if you notice:

  • A large number of advertisement pop-ups appearing every time you browse the web
  • New bookmarks or favorites that you didn’t set
  • Your browser goes to company websites or affiliate pages instead of your homepage
  • Changes to your system settings
  • Your computer is running slower than normal
  • Your computer crashes often or doesn’t function properly
  • You are missing files that you didn’t delete yourself

If you find that your computer is acting irregularly or displaying the qualities listed above, you might have a malware infection.

How to recover from malware

In the event of a malware infection, the first step is isolating the infected file or files. As harmful as a malware infection is, it’s possible to limit the damages if you can locate the source of the problem. Remove all devices that you believe to be infected from your home network to cut them off from other devices on the same network.

Try to gather as much information as you can about the infection. Use messages and file dates to determine when the infection started and what files it impacted. If you can identify the type of malware, it can help you learn what prevention steps you need to take in the future.

After you’ve isolated the problem, run an antivirus scan to detect and eliminate the issue. If the malware has taken root deep enough, you may need to reset your system. If you perform data backups regularly, this shouldn’t be detrimental, as you will have a copy of your files and data to restore afterwards.

Regardless of whether you already backed up your data before the infection, make sure to do it again when the malware is cleared from your system. If you experience another infection in the future, performing regular data backups will minimize damages and protect data important to you.

If you believe your information has stolen or think you might be a victim of identity theft due to a malware attack, contact the police or local law enforcement agencies to help you move forward.

What anti-malware software should I use?

Free anti-malware software

Users have many choices when it comes to anti-malware software. Some companies offer free software downloads for users to protect their systems at no cost. If a free program is what you're after, we recommend Ad-Aware Free. It allows you to schedule daily antivirus scans with real-time security updates. 

Spybot Search & Destroy and Microsoft Security Essentials are also great programs if you want to save money and still protect your devices.

Though free anti-spyware software works, we have found that the paid versions of anti-spyware and antivirus programs are better.  They offer better all-around security, detection, and protection.

For the best overall coverage, AVG Internet Security has a great security package for only a few dollars a month. They offer a free version as well, but their Ultimate version provides the best protection. You also get access to their VPN and anti-tracking services.

ESET Smart Security is another great option. In addition to excellent antivirus protection, the program provides its own password manager for users and free photo encryption. PC Tools Spyware Doctor works well as a base program to spot and eliminate all kinds of malware, including spyware, Trojans, adware, and keyloggers.