What is Malware?

Malware, or malicious software, is a file or program deliberately designed to harm the machine it infects. There is a wide variety of malware, and the term covers viruses, computer worms, spyware, ransomware, adware, and so-called Trojan horses.

Since 2009, the total number of recorded malware infections has risen from 12.4 million to 812.67 million, and the installation of malicious software has significant real worlds costs.

Around 34% of businesses hit with malware attacks took at least a week to regain full access to their data, and the total cost of malware infections will exceed $20 billion by 2021.

What Does Malware Do?

Malware is a blanket term that covers a wide variety of malicious software without any specific definition. Around 230,000 new malware samples are discovered every day, each performing a slightly different process that harms its target.

However, some common forms of malware are:

Ransomware

Ransomware is designed to encrypt the files of the system it is installed on, preventing access to them. The user will then receive instructions on how to unencrypt their files, usually in return for a financial ransom.

These ransoms are usually paid in bitcoin to render them untraceable.

A variant of ransomware, called leakware of doxware, threatens to post the user’s files to a public forum unless the ransom is paid.

The most famous ransomware example is WannaCry, which infected around 230,000 computers globally and cost an estimated $4 billion.

Viruses

Viruses are self-replicating malicious code or programs that infect individual computers or whole networks and execute unwanted functions.

A virus might cause your computer to lock up or crash, it might send mass emails containing copies of itself from your email account, or it might cause your web browser to open large numbers of advertising popups.

Computer Worm

Similar to a virus, a computer worm is a malicious program that spreads rapidly from computer to computer without human interaction.

Worms can be used to access sensitive data, cause computer systems to crash, rewrite essential files, or just replicate over and over again to use up system resources.

Trojan Horse

Trojan horses often appear as legitimate programs, such as software updates for standard programs like Adobe Acrobat or Java. Once downloaded, the Trojan horse will begin to enact malicious factions, such as creating a backdoor to you computer that cybercriminals can access.

Spyware

Once installed on your computer, spyware tracks what you are doing and sends it back to whoever designed the spyware.

Spyware covers many malware infections, including adware, which tracks your spending habits and bombards you with popups, and keyloggers, which record your keystrokes.

How Do I Know If I Have Malware

Common signs that you have a malware infection include a sudden increase in crashes or freezes. You might notice unusual program activity, with lots of programs you don’t recognize appearing in your task manager, or a huge increase in popups when you are trying to use your internet browser.

How Do I Remove Malware from My Device?

There are many anti-malware programs on the market to protect your device or network from malware infections. Most require a subscription fee. However, there are some free options.

One of the most common is Windows Defender. An anti-malware software that is bundled with Windows 10 operating system, Windows Defender can scan your system for a wide variety of malware.

To be at its most effective, Windows Defender needs to be regularly updated, and you will need to run regular “Full” scans of your computer. These scans can be scheduled to happen outside of working hours to prevent any unnecessary slowdown.

How Do I Prevent a Malware Infection

Having an effective anti-malware program installed and updating and running it regularly is an excellent preventative measure. However, the best way to avoid getting infected with malware is to practice safe online behavior.

Around 92% of malware is delivered simply by email using a technique called phishing.

Those targeted by malware phishing attacks are sent a seemingly legitimate email from a trusted company such as Paypal, Amazon, Apple, or a major bank. Opening these emails, or an attachment to the email, infects your computer with malware.

Developing a good understanding of how malware works and learning how to spot suspicious programs or emails is one of the best defenses against infection.

For businesses, rigorous staff training on how to spot malware, coupled with strong web browser-level security and robust threat detection and elimination policies, is the best way to prevent malware from spreading.