Insider Threats in Cybersecurity

When you think about security, it's usually from external factors. We lock the doors to our homes and businesses, when we go to the gym our belongings are kept safe in locked lockers from theft, and our computers and phones have security measures in place to keep people out.

Our focus is on external threats but the biggest danger can come from within — insider threats.

Consider the classic thriller When a Stranger Calls. The protagonist believes the threat is an outsider, only to discover the chilling reality: the call is coming from inside the house. This twist dramatically reinforces the concept of an insider threat.

Just like in the film, in any corporate setting, the danger does not always come from the outside. It could be a disgruntled employee, a negligent teammate, or even a malicious insider exploiting their access rights. These people can cause significant damage to your organization's sensitive data, reputation, and overall security.

What are insider threats?

Unlike external threats, insider threats are one of the most harmful risks to an organization's security and overall integrity. According to CISA, insider threats “present a complex and dynamic risk affecting the public and private domains of all critical infrastructure sectors.”

That’s because these threats typically originate from individuals within the organization, such as:

These individuals have inside information concerning your security practices, data, and computer systems. The threat posed by insiders is enormous due to their granted access and understanding of the organization, making their activities potentially far more harmful and harder to detect than external threats.

Insider threats are the cause of most data breaches and can cost organizations millions of dollars.

(Get to know today’s top threats to your business.)

Types of Insider Threats

There are two primary types of insider threats: intentional and unintentional. Understanding and mitigating both types of insider threats is crucial for maintaining a robust and secure environment.

Intentional insider threats

Intentional insiders are individuals who deliberately exploit their access to damage the organization. Typically, these individuals have malicious intent — they mean to cause harm or to otherwise enrich themselves.

Intentional insider threats have been depicted in movies like Office Space and Hackers to comedic effect — and yet their damage can be huge. In both, a computer program designed to divert small amounts of money per transaction was used to steal thousands of dollars from the company.

Examples of intentional insider threats include:

Unintentional insider threats

Unintentional insider threats occur when employees accidentally cause security breacheswithout intending to.

Accidents may include actions like emailing sensitive documents to their personal email address so they can work over the weekend. Increasingly, however, these unintended threats are a result of social engineering: that is, an unsuspecting insider may be coerced or bribed into actions that undermine the organization's security. (This is known as social engineering.)

These threats can happen due to human error, lack of awareness, negligence, or simply being untrained in security protocols. Examples of unintentional insider threats include:

Insider threats — whether intentional or not — can cause severe and costly damage to an organization. They can lead to:

Real-life examples of insider threats

Insider threats have caused severe damage to numerous high-profile companies, reinforcing the critical need for insider threat management. This time, let’s skip the silver screen and look at three real-life examples.

City of San Francisco (2008)

In 2008, network admin Terry Childs locked the city out of its FiberWAN networking system, preventing valid users from accessing email, payroll, police records and more. Users were locked out of the system for nine days before Childs finally gave up the passwords.

The lockout cost the City of San Francisco approximately $900,000, simply trying to regain control of their own network.

(Know the basics of network security.)

Marriott Hotel (2010s)

Marriott Hotels were victims of a major database breach that left over 500 million customer details exposed. The breach occurred through a reservation database that was acquired as part of Starwood Hotels & Resorts Worldwide.

It wasn’t until 2018 that the company discovered unauthorized access to its network — with some data being stolen as early as 2014. The data breach cost Marriott an estimated £18.4 million.

X, fka Twitter (2020)

On July 15, 2020, hackers used social engineering to gain access to Twitter's administrative tools, compromising 130 high-profile Twitter accounts to promote a Bitcoin scam. Within minutes of the initial tweets, over 320 transactions occurred, depositing bitcoins worth over $100,000 into an account before the scam messages were eventually removed by Twitter.

Best practices for mitigating insider threats

Like most areas of cybersecurity, mitigation requires continuous security monitoring (which Splunk can help you with). Proper security protocols, employee training, and continuous monitoring are crucial in mitigating insider threats. Some best practices include:

(Learn about incident response & common incident response metrics.)

Minimizing your risk of insider threats

No matter your size or your industry, insider threats pose a significant risk to organizations. Having a better understanding of the types of insider threats, potential consequences, and best practices for mitigating them is crucial in maintaining a secure environment for your organization.

By implementing proper security protocols and employee training, along with continuous monitoring and incident response plans, organizations can better protect themselves against insider threats and minimize the potential damage they can cause.

As technology continues to advance, so do the methods used by insiders to cause harm — whether intentionally or not. Therefore, it is crucial to stay vigilant and proactive in mitigating insider threats to safeguard your organization's sensitive data and reputation.

Let us all strive towards creating a safe and secure digital environment for everyone.

FAQs about Insider Threats in Cybersecurity

Whatis an insider threat?
An insider threat is a security risk that originates from within the targeted organization. It typically involves a current or former employee, contractor, or business partner who has inside information concerning the organization's security practices, data, and computer systems.
What are the types of insider threats?
Insider threats can be categorized as malicious insiders, negligent insiders, and infiltrators. Malicious insiders intentionally cause harm, negligent insiders unintentionally cause harm through carelessness, and infiltrators are external attackers who gain insider access.
What are common indicators of insider threats?
Common indicators include unusual access to sensitive data, attempts to bypass security controls, downloading large amounts of data, and changes in user behavior such as working odd hours or accessing systems not required for their role.
How can organizations detect insider threats?
Organizations can detect insider threats by monitoring user activity, implementing behavioral analytics, using data loss prevention tools, and conducting regular audits of access and usage logs.
How can organizations prevent insider threats?
Prevention strategies include enforcing the principle of least privilege, providing security awareness training, monitoring privileged accounts, and establishing clear policies and procedures for data access and handling.

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