How to prevent data breaches that involve your own current or ex-employees

Ambulance Victoria was thrust into the spotlight due to a massive data breach involving the personal and financial data of up to 3,000 employees. Reports suggest that a former employee unlawfully transferred sensitive data during their final days of access.

The information accessed included:

• Staff names, email accounts, and contact information

• Home addresses and emergency contact details

• Bank account numbers, superannuation data, and ATO information

• Personal identifiers such as gender, date of birth, nationality, and residency status

The financial and psychological toll on employees not to mention the reputational and legal consequences for the organisation could be significant. Ambulance Victoria’s swift response, including notification of authorities and support for staff, is commendable. However, the real question is: Could this have been prevented? The answer is yes.

Lessons learned and solutions for the future

The Ambulance Victoria incident wasn’t the result of an outside hacker exploiting a vulnerability. It was someone who still had legitimate access to confidential and sensitive information. This is a critical distinction because insider threats are among the most difficult to detect and prevent, especially without the right systems and processes in place.

Here are three key strategies any business can implement to avoid similar scenarios:

1. Implement role-based access and automated offboarding

One of the most common mistakes organisations make is failing to restrict access based on role and tenure. In this case, the former employee still had full access to sensitive files during their final days.

Solution: Implement strict role-based access controls and automated off-boarding protocols. When an employee leaves or even signals their intent to leave their access is immediately audited, flagged, and scaled down. This eliminates unnecessary exposure during the most vulnerable transition periods.

2. Real-time monitoring and behavioural analytics

Ambulance Victoria detected the breach after the fact once the files were already transferred.

Solution: Deploy real-time monitoring tools combined with AI-driven behavioural analytics. If an employee suddenly begins downloading large amounts of data, accessing files they’ve never touched before, or connecting from unusual locations or devices, systems can detect and alert this activity within seconds. Suspicious activity can be blocked automatically, reducing the chance of a breach.

3. Employee awareness and response preparedness

While Ambulance Victoria advised employees to update passwords and enable MFA after the breach, this reactive approach can only go so far.

Solution: Build a proactive security culture. This includes:

• Regular training on identifying phishing attempts

• Mandatory MFA across all platforms

• Secure communication protocols

• Simulated cyber-attack drills so teams know exactly how to respond

When your staff knows how to recognise and report suspicious activity early, you add a powerful human layer to your cyber defence.

What to do if you’ve been breached

Despite best efforts, no system is 100% invulnerable. That’s why we not only focuses on prevention, but also incident response. In the case of a breach, here’s what we recommend:

1. Isolate the threat: Immediately disable affected accounts and disconnect impacted systems.

2. Notify stakeholders: Transparency is crucial: inform staff, customers, and relevant authorities (like the Office of the Australian Information Commissioner OAIC)

3. Launch a forensic investigation: Determine how the breach occurred and what data was compromised.

4. Support your people: Provide case managers and tools to monitor financial activity.

5. Review and adapt policies: Learn from the incident and fortify your defences for the future.

The bottom line

The Ambulance Victoria breach is a painful reminder that cyber security is no longer just an IT issue, it's a leadership issue. Whether you're in healthcare, finance, insurance, or property, protecting your data is protecting your people.

At Revio, we help organisations build resilience, not just react to a crisis. Because the cost of prevention is always less than the cost of recovery.