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What are system and network attacks?

There are many threats to the security of your systems, network, and data. These can range from technical threats like denial-of-service and ransomware, to individual threats like malicious insiders and business email compromise.

Targeted attacks of this nature could result in a data breach or financial loss. Read through our advice below on how to prepare your organisation against some of these threats.

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Report and recover from system and network attacks

Ransomware, malicious insiders, and denial-of-service attacks. Find out what to do, who to contact, and how to avoid attacks in future.

Preparing for and Responding to Denial-of-Service Attacks

Although organisations cannot avoid being targeted by denial-of-service attacks, there are a number of measures that organisations can implement to prepare for and potentially reduce the impact if targeted. Preparing for denial-of-service attacks before they occur is by far the best strategy, it is very difficult to respond once they begin and efforts at this stage are unlikely to be effective.

Malicious insiders

Malicious insiders can be employees, former employees, contractors or business associates who have legitimate access to your systems and data, but use that access to destroy data, steal data or sabotage your systems.

Data Spill Management Guide

A data spill is the accidental or deliberate exposure of data into an uncontrolled or unauthorised environment. A data spill is sometimes referred to as data breach or a data leak.


Malware (short for 'malicious software') is software that cybercriminals use to harm your computer system or network. Cybercriminals can use malware to gain access to your computer without you knowing, in targeted or broad-based attacks.


Read through the following case studies and learn from other Australians about how ransomware has affected them.

Business email compromise

Learn about email phishing and what to do if you are scammed out of money, goods or information.


Cryptocurrency mining (cryptomining) uses the processing power of computers to solve complex mathematical problems and verify cybercurrency transactions. The miners are then rewarded with a small amount of cybercurrency.

Small Business Cyber Security Guide

This guide has been developed to help small businesses protect themselves from the most common cyber security incidents.

Essential Eight

While no set of mitigation strategies are guaranteed to protect against all cyber threats, organisations are recommended to implement eight essential mitigation strategies from ACSC's Strategies to Mitigate Cyber Security Incidents as a baseline.

Strategies to Mitigate Cyber Security Incidents

The Australian Cyber Security Centre (ACSC) has developed prioritised mitigation strategies to help cyber security professionals in all organisations mitigate cyber security incidents caused by various cyber threats.

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