The Main Differences Between All Computer Malware

Server, Networking & Security
  • In today's digital and technologically advanced world, cyber security is one of the most important aspects you simply cannot neglect both for personal and especially business uses.
  • For that reason, you need to clearly know what a computer virus, a computer worm, a Trojan horse virus and a blended threat are and how best avoid them.
  • Find out more by reading this article where we break them down separately for you.

computer virus

Understanding the differences between a computer virus, computer worm, Trojan horse virus and blended threat lets you know how to better protect your computer from any type of computer malware both for your personal and business use.

The Main Differences Between All Computer Malware

What is a computer virus?

Like the human virus, a computer virus ranges in severity. They are always attached to executable files on your computer. What does this mean? It means you are only going to be infected by the computer virus when the executable files is run. The executable file will always be sitting somewhere on your computer, residing on a USB stick or your favorite collection of Freeware software.

The damage of a computer virus can be annoying because it can completely destroy your hardware, software and your files. Twill almost always start infecting other computers on the same network.

What Are The Differences Between VIRUS, WORM, TROJAN HORSE and BLENDED?

What's a computer worm?

Worms are not the ones found in the garden and used for fishing.

A computer worm is very similar to the computer virus and in many instances, is considered a sub-class of a computer virus. The only difference is that a computer worm can spread without human interaction from computer to computer - meaning, the computer worm does not need to be executed by you to spread. 

The non-garden variety - the computer worm, does this by taking advantage of files or information transport programs on the computer which will allow it to spread (information transport programs examples are email etc...).

The largest amount of damage from a computer worm is its ability to replicate quickly and spread amongst computers across your network. Just imagine a computer worm sending to your address book, then the address book of your contacts. That computer worm would have a devastating effect on 1000 of systems within a short period of time. 

The very nature of the computer worm spreading across systems means massive resource loads on large system causing servers to crash and web servers to be unavailable; and in most cases the computer worm brings a complete halt to a company's network.

The Main Differences Between All Computer Malware

What is Trojan Horse?

The mythical Trojan horse the Greeks used to enter the city of Troy. 

Trojan horse virus looks like software you need or want to get onto your computer because you downloaded it. Once you install this software, a Trojan horse virus can cause all sorts of danger from annoying changes to your operating system to full blown system changes and deletion of files.

Trojan horses virus almost always opens a backdoor program for malicious users to login and execute other code, and grab sensitive data i.e. your bank details.

Unlike the aforementioned computer virus and computer worm, a Trojan horse virus does not replicate itself on the computer.

The Main Differences Between All Computer Malware

What is a Blended threat?

The blended threat, big one, as you might've you guessed, takes all the best characteristics of the computer virus, computer worm and Trojan horse virus and commits a devastating attack on your systems/network. That's exactly what the Blended threat does.

The blended threat accesses servers, looking out for vulnerabilities on the Internet to initiate, transmit and, eventually, start an attack. The blended threat causes harm to the infected PC and networks. The blended threat does this using different methods with the attack coming from different or multiple points. What the blended threat does afterward is to exploit all the vulnerabilities found on the system.

It can only be considered as a blended threat once the attack releases a massive payload from multiple sources.

An example of this is executing a DoS (Denial of Service attack), while installing a backdoor vulnerability and attacking files, registry, HTML taking down multiple parts of the network at the same time causing massive downtime. This blended threat will spread via, email, IRC, and file-sharing networks.

Blended threat is considered to be the worst risk to security since the inception of viruses, as a blended threat also requires no human intervention to propagate across networks.

3 critical areas to protect your business from computer malware:

  • Always make sure your Operating System is up-to-date, i.e. you have patches installed regularly and not just windows software updates,
  • Virus software is installed, updated and actively running and make sure you are running a full disk scan once a week if not more,
  • Use a Firewall to protect from unauthorised access to your system. Have a good firewall on the computer as well as a firewall on the company gateway.

If the 3 Critical areas are being looked after then your chance of being hit is massively reduced.


Do not forget this one. 

Educate your staff and have best practices in place for computer usage, don't just click 'enter your username here' in the email.

How do you protect your servers from computer virus, computer worm, Tojan horse virus and blended threat?

Shaun Goethals

Director / Principal Consultant at

My personal life is at the opposite end to the working life. I have a small property North of Melbourne with lots of animals a few kids and wife, I have been working in IT for over 15 years and in 2013 started IT System Solutions. My focus with IT is to support small to medium sized businesses who need reliable IT support and flexible solutions. We especially enjoy working with start-ups in helping them navigate the technology they need.

Comments (3)
Rebecca Carroll-Bell

Rebecca Carroll-Bell at

Great article Shaun. We were hit by a...something last week. A message came up telling us that our details had been sent to Interpol and we had to pay $100 otherwise we'd be locked out of our computer for good. Luckily hubby was able to find and carry out the solution straight away. Scary!

Janny Wilson

Janny Wilson

You discussed on this post about all type of computer malware virus, how they can affect our computer. I really say that your post is very informative. Keep sharing this type of content. Resolve your HP computer related issue at HP Computer Support. 

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