Why Your Company’s Biggest Cybersecurity Threat Might Be Internal

In today's business environment, cybersecurity threats are evolving rapidly, and companies are investing millions in fortifying their defences against external attackers. Firewalls, anti-virus software, and secure networks are all vital components of a solid cybersecurity strategy, but there’s one critical element that many companies overlook — their own employees. In fact, internal threats have become one of the most dangerous and underestimated risks to corporate security. These threats don’t always come from malicious intent; they can often stem from simple human error, lack of awareness, or manipulation by sophisticated attackers.

Let’s take a closer look at why your employees might be your company's biggest cybersecurity vulnerability and how you can mitigate the risk.

The Rise of Insider Threats

An insider threat refers to any security risk that originates from within the organisation, whether intentional or accidental. It can come from current or former employees, contractors, or anyone with access to sensitive data or systems. Insider threats are often more difficult to detect and prevent than external ones because they involve individuals who already have a certain level of trust and access within the company.

There are generally three types of insider threats:

1. Malicious insiders – Employees or contractors who intentionally steal data or damage systems for financial gain, personal revenge, or in coordination with external attackers.
2. Negligent insiders – Employees who unintentionally expose sensitive information or fall victim to phishing attacks due to lack of awareness or poor cybersecurity habits.
3. Compromised insiders – Individuals whose accounts or credentials have been hacked by an external actor, who then uses their access to move through internal systems unnoticed.

2024 Verizon Data Breach Investigations Report (DBIR) states: ‘68% of breaches involved a non-malicious human element, like a person falling victim to a social engineering attack or making an error’.

Deepfakes: The New Frontier of Cyber Deception

One of the most alarming developments in internal cybersecurity threats is the rise of deepfakes — AI-generated fake audio or video that convincingly mimics real people. In the hands of cybercriminals, deepfakes can be weaponised to manipulate or deceive employees into compromising sensitive information or transferring money.

Imagine receiving a video call from what appears to be your CEO, instructing you to immediately transfer funds to a supplier, only to find out later that it wasn’t your CEO at all, but a deepfake created by cybercriminals. There have already been real-world cases of deepfake audio (vishing attacks) being used to trick employees into authorising fraudulent transactions.

Because deepfakes exploit human trust, they are particularly dangerous in corporate environments where visual or verbal cues are relied upon for decision-making. Employees might not even realise they’ve been manipulated until it’s too late. This highlights the need for robust internal security measures and ongoing training to help staff recognise potential deepfake scams.

Social Engineering: The Human Factor

Deepfakes are just one tool in a broader category of threats known as social engineering — tactics used to manipulate employees into bypassing normal security protocols. Cybercriminals may pose as trusted colleagues, IT personnel, or even vendors, gaining access to systems by exploiting human error or trust. These schemes can be remarkably effective and difficult to detect.

Phishing emails remain one of the most common forms of social engineering. Employees are tricked into clicking on malicious links, downloading malware, or providing sensitive information such as passwords. Even with advanced technical defences in place, it only takes one employee mistake to create a significant security breach.

The Cost of Internal Threats

The financial and reputational costs of internal cybersecurity incidents are staggering. According to a Ponemon Institute’s global report on the costs of insider threats (2022) reveals, ‘ insider threat incidents have risen 44% over the past two years, with costs per incident up more than a third to $15.38 million’. These breaches can result in loss of customer trust, legal consequences, and significant operational disruptions.

In many cases, internal threats are more damaging than external attacks because insiders already have the access needed to exploit systems. While hackers on the outside are working hard to penetrate your defenses, insiders often already possess the "keys to the kingdom."

How to Mitigate the Risk of Internal Threats

So, what can companies do to address the growing problem of internal cybersecurity threats? Here are some steps you can take to reduce your risk:

• Implement Role-Based Access Controls (RBAC)
  Limit access to sensitive data and systems based on employees’ roles and responsibilities. Not everyone needs access to everything. By restricting access to only what is necessary, you minimise the risk of data being compromised by a malicious insider or through stolen credentials.
• Employee Training and Awareness
  The most effective defense against human error and social engineering attacks is comprehensive cybersecurity training. A great example of this is this digital training course on CEO Fraud and Deepfake by DSN train. Employees need to be regularly educated on the latest threats, including deepfakes and phishing attacks. Interactive training that includes simulations can help employees recognise these risks and react appropriately.
• Monitor and Audit Activity
  Use monitoring tools to detect suspicious activities, such as unusual login times, excessive downloading of sensitive files, or access attempts from unfamiliar locations. Regular audits of employee activity can help catch potential security breaches early.
• Multi-Factor Authentication (MFA)
  Implement MFA for all sensitive systems and data. This adds an extra layer of security, ensuring that even if an employee’s credentials are compromised, the attacker cannot gain access without a second form of verification.
• Incident Response Plan
  Prepare for the worst by having a clear incident response plan in place. If a breach does occur, quick and decisive action can reduce the damage and help contain the fallout.

Conclusion: Invest in People as Your First Line of Defense

While external attacks are a serious concern, the internal threat landscape is becoming increasingly complex and dangerous, especially with the rise of deepfakes and social engineering techniques. By investing in employee training and creating a culture of cybersecurity and information security awareness, your company can significantly reduce the risk of internal threats. A wide range of ready to deploy courses dealing with everything from cybersecurity, phishing, smishing, social engineering and deep fakes to sharpen your team’s awareness can be found here. Remember, even the most advanced technology can be undermined by human error, which is why educating and empowering your team is key to safeguarding your business.

Your company’s greatest cybersecurity asset — and potentially its biggest vulnerability — is your workforce. Make sure they are equipped to recognise and respond to the threats they face.