Ransomware Trends in Australian Businesses and How to Prepare

Ransomware Landscape in Australia

Ransomware remains one of the most pressing cyber threats for Australian businesses in 2026. According to the Australian Signals Directorate’s (ASD) Annual Cyber Threat Report 2024–2025, there has been a significant rise in ransomware attacks targeting both small and medium enterprises (SMEs) and large corporations. These attacks often exploit software vulnerabilities, misconfigured cloud environments, and weak endpoint security. Double extortion tactics, in which attackers encrypt data and threaten to leak it, are increasingly common and designed to maximise financial gain.

Recent incidents have demonstrated that ransomware is no longer confined to IT systems but can also impact operational technology (OT) and industrial control systems (ICS), especially in sectors like manufacturing, energy and healthcare. The Australian Cyber Security Centre (ACSC) has issued updated guidance to help organisations understand and mitigate these evolving threats.

Current Ransomware Trends in Australia

Several trends are emerging in the ransomware landscape in Australia. One is the use of agentic AI by threat actors to automate attacks and identify vulnerabilities at scale. The ACSC has highlighted in its guidance on agentic AI that while such AI can be a powerful tool for businesses, it can also be weaponised for malicious purposes. Threat groups are using AI to generate convincing phishing emails, automate reconnaissance and customise payloads for specific targets.

Ransomware-as-a-service (RaaS) platforms continue to lower the barrier to entry for cybercriminals, enabling even less technically skilled attackers to launch sophisticated campaigns. These platforms often operate in underground markets and provide everything from malware code to customer support for ransom negotiations. This commodification of cybercrime means ransomware attacks are becoming more frequent and harder to attribute.

Preparing for Ransomware Attacks

Preparation is key to minimising the impact of ransomware attacks. A comprehensive strategy should include both proactive and reactive measures. The following steps should be implemented to enhance organisational resilience:

• Implement the ACSC Essential Eight: The ACSC Essential Eight is a baseline set of mitigation strategies designed to prevent cyber attacks. It includes application whitelisting, patching, multi-factor authentication and system hardening. While not a legal requirement for all organisations, it is strongly recommended and forms part of the Information Security Manual (ISM). For example, application whitelisting can prevent unapproved executables from running, reducing the risk of ransomware deployment.
• Conduct regular security assessments: Regular penetration testing and vulnerability assessments can help identify and remediate weaknesses before they are exploited. Continuous security validation is particularly effective in ensuring that controls remain effective over time. This is especially important in environments where systems are frequently updated or new services are added.
• Backup and disaster recovery planning: Ensure that backups are performed regularly, stored securely and tested for recoverability. A robust disaster recovery plan should be in place to restore operations quickly in the event of an attack. Backups must be stored offline and in isolated environments to prevent them from being encrypted during an attack.
• Employee training and awareness: Human error remains a common entry point for ransomware. Regular training and simulated phishing exercises can help reduce the risk of social engineering attacks. Consider implementing mandatory training modules for all staff, especially those in high-risk roles such as finance, HR and IT.
• Secure cloud and API environments: As organisations increasingly move to hybrid and cloud environments, ensuring the security of cloud infrastructure and APIs is critical. This includes identity and access management, encryption and logging. Misconfigured cloud storage buckets remain a common vulnerability that ransomware attackers exploit to gain initial access.

Continuous Security Validation and Penetration Testing

Traditional security assessments are not sufficient to detect and respond to modern ransomware threats. Continuous security validation, such as that provided by PentestOps, enables organisations to simulate real-world attacks on an ongoing basis. This approach helps identify gaps in security controls, validate the effectiveness of existing defences and improve incident response readiness.

Penetration testing should be conducted not just annually, but continuously, to reflect the evolving threat landscape. This includes testing for vulnerabilities in both IT and OT systems, as well as third-party applications and APIs. When combined with security validation tools, penetration testing can provide organisations with a dynamic view of their attack surface and help them respond to threats in real time. Consider integrating automated testing into your DevOps pipeline to ensure that security is maintained throughout the software lifecycle.

Responding to Ransomware Attacks

In the event of a ransomware attack, a swift and coordinated response is essential. The following actions should be taken immediately:

1. Isolate affected systems: Disconnect compromised systems from the network to prevent lateral movement of the ransomware. This is particularly important in environments with interconnected systems such as manufacturing or healthcare.
2. Activate the incident response plan: Follow the organisation’s incident response plan and notify relevant stakeholders, including IT, legal and executive teams. Ensure that the plan includes roles and responsibilities, communication protocols and escalation procedures.
3. Contact law enforcement and the ACSC: Reporting the attack to the ACSC and local law enforcement can provide access to expert support and intelligence on similar incidents. The ACSC’s Information Security Manual provides guidance on how to report and respond to ransomware attacks.
4. Assess the damage and restore from backups: Determine the extent of the attack and begin restoring systems from clean backups. Avoid paying ransoms, as this does not guarantee data recovery and may encourage further attacks. Consider using immutable backups to prevent them from being overwritten or deleted.
5. Conduct a post-incident review: Analyse the attack to understand how it occurred and implement additional controls to prevent recurrence. This is a key opportunity to refine your security strategy and improve resilience for future threats.

Regulatory and Compliance Considerations

Organisations must also consider their legal and regulatory obligations when responding to ransomware attacks. Under the Privacy Act 1988 and the Notifiable Data Breaches (NDB) scheme, businesses must notify affected individuals and the Office of the Australian Information Commissioner (OAIC) if a data breach is likely to result in serious harm. APRA-regulated entities must also comply with CPS 234, which requires them to implement robust cyber security controls to protect against threats.

Consider the following compliance actions in the event of a ransomware attack:

• Review and update your organisation’s privacy policies and incident response plan to ensure compliance with the NDB scheme.
• Document all steps taken during the incident and retain records for potential audits or legal proceedings.
• Engage legal counsel to assess the impact of the breach and ensure that all reporting obligations are met.

Cost and Resource Considerations

Implementing a robust ransomware defence strategy requires both financial and human resources. Consider the following costs and trade-offs when planning your response:

Real-World Scenarios

Consider a 40-person firm that relies heavily on cloud-based accounting software and remote access for its finance team. An attacker gains access through a phishing email, exploits a misconfigured cloud storage bucket and deploys ransomware across the network. The business has no immutable backups, and the ransom demand is in cryptocurrency. The firm must now decide whether to pay the ransom, which may not guarantee data recovery, or attempt to restore from backups, which are also encrypted. In this scenario, the organisation’s lack of continuous monitoring and backup testing leads to significant downtime and financial loss.

Now consider a similar organisation that has implemented the ACSC Essential Eight, conducts regular penetration testing and maintains offline backups. When an attacker attempts to deploy ransomware, the organisation’s security tools detect the activity and isolate the affected systems. The organisation is able to restore from backups within 24 hours, minimising downtime and financial impact. This example highlights the importance of proactive security measures in mitigating the risk of ransomware attacks.

Conclusion

Ransomware attacks are becoming more sophisticated and damaging, particularly in Australia. By understanding current trends and implementing a comprehensive security strategy, organisations can significantly reduce their risk. Continuous security validation and penetration testing are essential tools for identifying and addressing vulnerabilities before they are exploited. With the right approach, businesses can not only defend against ransomware but also recover quickly and effectively in the event of an attack. To begin securing your organisation against these evolving threats, assess your current security posture and identify areas for improvement.