Malware is a general term that encompasses all forms of malicious software that can potentially infect your computer or systems. Malware is the force behind most cyberattacks, from data theft to identity fraud and large-scale data breaches. A malware infection can cause all sorts of serious problems for your organisation, including allowing cybercriminals to access your site or system controls, change settings, steal company and personal data, embed malicious ads or deface your website. It can even result in your site being removed from Google’s search results or in absolute worst cases, blackmail. Ultimately, a malware attack can cost you revenue and your reputation. 

Here are the 9 most common types of malware in the cybercriminal arsenal and the most effective ways to avoid them.

1. Ransomware

This type of malware attempts to blackmail you by blocking access to your system and demanding you pay an amount of money to regain access, or will threaten to expose your private details. This type of malware is typically a criminal moneymaking scheme and usually installed through deceptive links in an email message, instant message or website.


2. Spyware

This is malicious software that has been installed on your device and will try to gather your private information and monitor your activities, reporting the information to an outside party. But how does it end up on your device? 

Spyware software can be installed on a computer through the download of:

  • Third-party web browser toolbars or add-ins.
  • Media programs like video or audio players 
  • Packages promoted be “anti-spyware” that actually contain spyware, also known as scareware.
  • Other “freeware” applications.


So named for their trojan horse qualities and often presenting as legitimate and harmless software such as games or utilities, once installed, this malware will attack your computer or attempt to harvest valuable data. While it won’t self-replicate like a virus, it can be programmed to create an unauthorised access point, making your system vulnerable to further ransomware and spyware.


This is aggressive advertising software that can bombard you with pop-ups, redirect you to advertising sites and change your internet browser and search settings. You typically pick up adware through a free software download, or by visiting a website that infects your computer with a ‘drive-by download’. This is when you initiate an unintended download of one or more files without your knowledge.


5. Worms

These self-replicating malware programs can duplicate themselves to spread to uninfected computers. Worms often consume large amounts of memory and bandwidth, so affected servers, networks and individual systems get overloaded and stop responding. Worms can significantly slow performance, not just on individual machines, but across entire networks. Worms are typically installed when victims click malicious links in targeted phishing attacks.

6. Viruses

A computer virus is a malicious code or program that interferes with a computer or website’s functioning. While early viruses were designed to harm systems and cause panic, today’s viruses are objective-based. Most viruses today are designed to remain undetectable while secretly funnelling valuable data. Viruses can inflict harm in many ways, such as logging your keystrokes, stealing sensitive information, and corrupting or deleting files. Hacktivists regularly employ viruses during attacks to try and gain control over company systems.

7. Rootkits

Rootkits are a variety of malware that take root deep in your system and grant unauthorised users access to your computer or website. Designed to remain hidden, they allow cybercriminals to take over your website or device without your knowledge. Since they’re so difficult to uncover, a rootkit can remain on your system or website and inflict ongoing damage over time. There is a variety of rootkits that can infect different parts of your computer with some attacking memory or hard drive, while others affect program function.

8. Keyloggers

Unlike many forms of malware, keyloggers are not a threat to the systems they infect. Keylogger is a type of spyware that records keystrokes from a keyboard, usually without the user knowing. Cybercriminals use keyloggers to gain access to passwords, account logins and other valuable information. They then use this data to access financial accounts, steal identities and sell personal data to third parties on the dark web.


9. Bots and botnets

Bots are programs that carry out designated tasks automatically. They are set-and-forget programs deployed across the internet, and when used maliciously, they carry out cybercriminal dirty work such as spamming attacks. One of the most popular forms of bot attack is Distributed Denial of Service (DDoS). These waves of automated traffic from attackers attempt to overwhelm systems through sheer volume. A botnet is a string of computers deploying bots across multiple networks to execute mass attacks.

How to avoid Malware

  • Make sure your anti-virus security is always up to date.
  • Never click on suspicious links in emails from known or unknown senders 
  • If you are the victim of a ransomware attack, don’t provide any financial details and contact your IT department immediately.
  • Never download free internet software without the approval of your IT department.
  • Concerned your computer has an infection? Get your software engineer to run a comprehensive system scan.
  • Set your computer to install security and software updates automatically.
  • If your system is unusually slow or you are having trouble accessing programs and information, alert your IT department immediately.
  • Avoid visiting unverified and potentially infected websites. 
  • If you are getting adware popups, ask your IT department to perform a cyber clean-up and system check.

Need reliable security?

Contact Evologic to design a complete cybersecurity solution tailored to your business with the reliability of ongoing support. We can also perform a Free Cybersecurity Checkup & Dark Web Scan to see if your company data has been compromised.

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