When we think of cyber threats, most of us imagine anonymous hackers or overseas attackers targeting systems from afar. But one of the most dangerous risks actually comes from the inside. Insider threats are caused by people within an organisation who are often overlooked, but they can do serious damage, especially in industries that keep our country running. In this blog, we will explore types of insider threats and personas, the real-world impacts of insider threats, and strategies to prevent this hidden danger from causing significant damage to the services society relies on. 

What exactly is an insider threat? 

According to the Australian Government’s 2023 guide, Countering the Insider Threat, an insider is anyone’s current or former employee, contractor, or service provider, who has legitimate access to a workplace’s systems, information, or physical areas. 

There are two types of insider threats: 

• Unintentional insiders – Those who make mistakes without realising the impact. 

• Intentional insiders – Those who knowingly cause harm, either for personal gain or under pressure. 

The guide breaks these down into five common personas: 

1. The Accidental Insider – Someone who makes an honest mistake due to poor training or a lack of awareness.

2. The Negligent Insider – Knows better but cuts corners or ignores rules.

3. The Self-Motivated Insider – Has their own agenda, whether it’s revenge, money, or personal beliefs.

4. The Recruited Insider – Is encouraged by an outsider (like a criminal group or foreign agent).

5. The Coerced Insider – Acts out of fear, blackmail, or manipulation. 

Insider threats don’t always involve someone being malicious or trying to sabotage systems. Sometimes it comes about by mistake, someone clicking on a dodgy link or sending an email to the wrong person. Whether intentional or not, the fallout can result in leaked sensitive data, disruption of services, or damage to the public’s trust.

In critical infrastructure sectors like energy, water, healthcare, or transport, the stakes are even higher. These services are essential to our daily lives, and even small disruptions can have devastating consequences.

Why this matters for critical infrastructure 

Insider threats can impact all organisations, but critical infrastructure is especially vulnerable. These industries keep society functioning, and they rely on trust, security, and smooth operations to do so. According to a recent report from the Cyber and Infrastructure Security Center, and in line with the Mandatory Cyber Incident Reporting (MCIR) obligation under the SOCI Act, there were numerous instances in the last year of data exposure, data theft, and data leak via insider threat. 

During a recent internal call, some real examples were mentioned: 

• Visiting delegations being used as distractions while someone sneaks onto a computer 

• No photos allowed on-site to prevent sensitive info getting out 

• No more than five external visitors at a time to keep things manageable 

• Keeping HR in the loop, since life changes (like financial stress or personal issues) can make someone more vulnerable. 

According to the CISC report, real-world de-identified examples of MCIR cyber incidents caused by insider actors included: 

Example 1: A contracted employee of a critical energy asset downloaded extensive amounts of confidential data to a personal hard drive upon their resignation at the company. This included technical plans/details on the layout of the facility and operational data. 

Example 2: An employee at a critical infrastructure asset forwarded numerous emails to their personal email account, with attachments that contained sensitive confidential information about the critical infrastructure. The employee then went overseas on holidays. 

Example 3: An employee didn’t have their systems access revoked after leaving the organisation. They subsequently used their access to download sensitive information. 

This all goes to show that threats aren’t always high-tech. They can be as simple as someone being in the wrong place at the wrong time with the wrong intentions. 

The real-world impact of insider threats 

The government’s guide outlines just how damaging these insider acts can be. The impacts go far beyond the IT department: 

• People get hurt – Mental stress, job loss, and in extreme cases, even physical danger. 

• Services get disrupted – Delays in healthcare, outages in energy, or chaos in transport. 

• Trust gets damaged – People lose faith in the system, and that’s hard to rebuild. 

• Money gets wasted – Resources that should go to the public end up fixing preventable mistakes. 

There are also reputational consequences. When a breach happens, it can take years to rebuild public trust, but in the meantime, critical operations might face scrutiny, audits, and funding issues. 

How can we prevent insider threats? 

Whilst there is no one-size-fits-all solution for preventing insider threats – every organisation is different – there are a few strategies proven to consistently work well. 

1. Lead with integrity

A strong culture begins with leadership. When leaders model integrity and accountability, it sets the tone for the entire organisation. Engaged and supported employees are much less likely to pose a risk. 

2. Keep everyone informed

Training can’t just be a one-off box to check during onboarding. Employees need regular reminders to know what’s okay, what’s not, and how to spot something suspicious. Empowering people to act when something feels “off” is just as important as having policies in place. 

3. Make it easy to speak up

If someone notices something odd, they need a safe, confidential way to report it. They need to trust they won’t be punished for doing the right thing. Anonymous reporting tools can be a great option here. 

4. Security at every level

This includes: 

• People: Proper vetting, clear policies, and support during tough times 

• Systems: Strong passwords, data access rules, and software monitoring 

• Spaces: Restricted zones, ID checks, and visitor escorts 

Spotting the red flags early 

Insider threats rarely come out of nowhere. There are often warning signs, like sudden behaviour changes, unexplained wealth, working odd hours, or trying to access systems they are unauthorised to. 

A good insider threat program will look at these indicators as patterns, not isolated events. Just because someone works late doesn’t mean they’re a threat, but if it’s combined with other signs, it may warrant a closer look. 

HR teams and managers are key here. Regular check-ins, listening to concerns, and watching for signs of stress can make a big difference. 

What if something does go wrong? 

Even with the best planning, things can still go wrong. That is why every organisation needs a response plan which details: 

• Who handles investigations 

• How to gather and review evidence 

• When to report to authorities like the National Anti-Corruption Commission 

Post incident reviews should always be conducted to understand what the gaps were and if the behaviour could have been detected earlier. It is not about blame but learning how to quickly identify, respond to, and prevent similar incidents from occuring in the future. 

It’s also important to remember: insider threats don’t always come from bad people. Sometimes, it’s good people who make bad choices when they are under pressure. Being proactive, not reactive, is the best strategy. 

In critical infrastructure, trust is everything 

Insider threats can be hard to predict and even harder to catch. But that doesn’t mean we are powerless. By focusing on people, culture, and clear processes, we can make a big impact. 

This isn’t just about cyber security, it’s about trust. And in critical infrastructure, trust is everything. 

Need help identifying potential threats in your organisation?

Our team of OT experts can help your organisation prevent threats before they become incidents. Get in touch to learn more about how we can empower your organisation to navigate the ever-evolving cyber landscape and stay one step ahead of potential threats.