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What is malware and why is it a cyber threat?

Malware can be invisible and have no known or noticeable effects and run on your computer undetected if it's well written

A cyber threat, or cyber security threat, is a malicious act that seeks to damage data, steal data, or disrupt digital life in general.

Cyber threats are a big deal. Cyber attacks can cause electrical blackouts, failure of military equipment and breaches of national security secrets. They can result in the theft of valuable, sensitive data like medical records. They can disrupt phone and computer networks or paralyse systems.

Cyber attacks include threats like computer viruses, data breaches, and Denial of Service (DoS) attacks.

One type of threat is malware.

Cyber threat: malware

Malicious software, or malware, is used by cyber criminals, hacktivists and nation states to disrupt computer operations, steal personal or professional data, bypass access controls and otherwise cause harm to the host system.

Appearing in the form of executable code, scripts, active content or other software variants, there are many different classes of malware which possess varying means of infecting machines and propagating themselves.

Malware types include worms, spyware, rimeware, adware, viruses, trojans and rootkit Click image to enlarge

Damaging impact

Malware can have a damaging impact on individuals and organisations: from causing your connection to slow down to stealing your information, crashing the system or even hijacking it.

Malware can be invisible and have no known or noticeable effects and run on your computer undetected if it’s well written. In some instances, organisations have discovered malware that was sitting on their network for a couple of years, undetected, slowly stealing information and causing extensive organisation and operational damage.

“Malware has remained at the heart of incidents affecting every sector, making up 30% of incidents reported to CERT-UK, and with the vast majority of these incidents allowing unauthorised access to a network or information held on it. Malware remains the greatest threat to cyber-security in the UK.”
(National Cyber Security Centre 2016: 2)


National Cyber Security Centre (2016) CERT-UK Annual Report 2015/16 [online]. available from [20 August 2019]

© Coventry University. CC BY-NC 4.0
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The Cyber Security Landscape

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