What Is Malware?


Next time you download a Microsoft Office attachment sent through email, take an extra second to think about it.

Is it coming from someone you know? Were you expecting this attachment? Have you scanned it?

Turns out that Office users were the most at risk of falling victim to email-based malware, according to the 2019 Internet Security Threat Report.

Further, the report found that employees of smaller organizations were more likely to be hit by email threats.

Malware comes in several different forms.


What Is Malware?

First of all, malware is a portmanteau of malicious software.

Malware is any file or program that can harm your computer or smartphone. It does this by:

  • Stealing, encrypting, or deleting data.
  • Altering or hijacking the core functions of your device.
  • Monitoring your activity without your consent.

Malware can be delivered through such channels a USB drive, an email attachment, or a software download.

Let’s take a look at the main types of malware.



Like a flu virus, a computer virus spreads rapidly.

A virus is malicious code and a program that affects how a computer functions. A virus can also replicate itself.

Viruses typically take the following forms:

  • Frequent pop-up windows or computer crashes.
  • Mass emails sent from your email account.
  • Unknown computer programs on your device.

If you notice any other unusual activities with your computer, those may also suggest a virus has infected your device.


A worm typically enters your system through a network or a downloaded file and, like viruses, spread rapidly.

Worms eat up processing power from operating systems, slowing down or entirely stopping the parts of the OS that are usually automatic. Infected computers may also exhibit unusual behavior from software programs, and they may trigger noises, images, or system warnings.

Once they’ve infected a system, worms spread to other systems and remain active on each of them.



Spyware is any software downloaded to a device that doesn’t have the user’s permission.

Like worms, a symptom of spyware includes degraded system performance.

One such example is a Trojan horse. Disguised as a legitimate program, Trojan horses sit quietly on your computer. They may look like a music file, a software program, or an advertisement. Meanwhile, the Trojan horse creates a backdoor to security system, allowing it to spy on your online activities and steal your passwords and other credentials.

Keyboard loggers are another type of spyware. This software logs every keystroke you make, allowing hackers access to credit card data, usernames, passwords, and other sensitive information.


How Can You Prevent Malware Attacks?

You can help to prevent malware attacks by taking the following steps:

  1. Keep your operating system and your software applications up to date, or ensure your company is doing through with a regular cybersecurity assessment.
  2. Use an antivirus program.
  3. Avoid clicking on website pop-ups.
  4. Scan email attachments before opening them.
  5. Companies with remote workers should require them to access their network through a VPN.


What Do I Do If My Device Is Infected With Malware?

File a ticket with your company’s IT support if you think you have any of these forms of malware.

If your phone or computer is performing more slowly than usual or you’re noticing some quirks, it’s best to get your device checked.

Download Our Security Awareness Guide

Read On