What Is an Insider Threat? Definition, Types, and Countermeasures

Your employees, business partners, and third-party contractors with legitimate access to your corporate infrastructure may pose significant risks to your cybersecurity. Intentionally or unintentionally, they can destroy or expose your valuable data, thus, putting your organization at risk for non-compliance, financial losses, reputation damage, etc.

It’s important to understand what insider threats are and what dangers they may pose to your organization. In this article, we give a detailed definition of insider threats, explore the causes of insider threats, types of risky insiders, and best practices for preventing, detecting, and mitigating insider attacks.

What is an insider threat?

An insider threat is a security risk that originates from within your organization. It occurs when your employees, contractors, or business partners misuse their access intentionally or unintentionally, harming your networks, systems, and data. Insider threats may manifest in different ways including negligence, data theft, system sabotage, fraud, and cyber attacks.

An insider threat is a malicious, careless or negligent threat to an organization that comes from people within the organization — such as employees, former employees, contractors or business associates — who have inside information concerning the organization’s security practices, data, and computer systems.

Gartner’s Market Guide for Insider Risk Management Solutions (subscription required)

Another insider threat meaning is proposed by the Cybersecurity and Infrastructure Security Agency (CISA). It defines an insider threat as “the potential for an insider to use their authorized access or understanding of an organization to harm that organization.” This harm may include malicious or unintentional acts that negatively affect the confidentiality, availability, and integrity of your organization’s critical data, personnel, or facilities.

Insider threats are on the rise and pose serious cybersecurity problems for many organizations. According to the 2022 Cost of Insider Threats Global Report by the Ponemon Institute [PDF], the frequency of insider threat incidents has increased by 14% in four years.

At the same time, the average annual cost of insider-related incidents increased almost twice as much – from $8.3 million in 2018 to $16.2 million in 2023, according to the 2023 Cost of Insider Risks Global Report by the Ponemon Institute.

Besides financial losses, organizations suffer from loss of critical data, brand damage, operational disruption, loss of revenue, legal liabilities, and more. 

Now, when we’ve discovered what insider threats are and how dangerous they can be, let’s explore what the types of insider threats are. 

Types of insider threats

While discussions on the topic are popular among cybersecurity specialists, there is no industry consensus for classifying types of insider threats in cybersecurity.

In the Market Guide for Insider Risk Management Solutions (subscription required), Gartner classifies insider threats according to three types of threat actors:

• Malicious insiders
• Careless insiders
• Compromised insiders

According to this classification, compromised accounts are also considered insider threats because when outsiders enter your infrastructure under the credentials of a legitimate user, the system sees them as insiders.

Intruders can steal user credentials by:

• Sending phishing emails
• Infecting computers with malware through a link in an email, files downloaded from a website, USB devices, etc.
• Phishing phone calls
• Pass-the-hash attacks, etc.

However, the most granular approach so far has been taken by Verizon. They split all insider threats into five insider threat categories:

This classification system covers a wide range of insider threats and reasons for attacks: malicious intentions, industrial espionage, negligence, emotional motivators, and even third-party vendor-related risks. Recent insider threat statistics show that most insider attacks are caused by employee carelessness – according to the 2023 Cost of Insider Risks Global Report by Ponemon, 55% of all incidents are caused by negligence. Yet, malicious insiders cost the most — on average $701,500 per incident, according to the same report.

By understanding the true nature of each type of insider threat, you can better understand the risks they pose to your company’s cybersecurity. In the next section, we talk about the main cybersecurity risks and challenges of insider threats.

The key risks and challenges of insider threats

The main problem with insider attacks, in contrast to outside attacks, is that they can go unnoticed not only for weeks but for months. The average number of days to contain an incident stretched to 86 in 2023 according to the 2023 Cost of Insider Risks Global Report by Ponemon Institute.

Whereas external actors behave suspiciously from the moment they invade your system, malicious insiders typically act normally and spend a limited amount of time on their malicious actions. That’s why it’s challenging to detect malicious insider attacks. 

Insider threats are more challenging than external cyberattacks because:

• Insiders have legitimate access to your infrastructure
• Insiders know (or can easily find out) where you store your most valuable data
• Insiders know your cybersecurity system from within, which means it’s easier for them to bypass it.

Gartner defines the three following three types of insider threat activities as follows:

Fraud activities include misusing your valuable assets for personal gain, phishing campaigns, and misrepresentation.

Data theft is carrying out an unauthorized data transfer from a corporate computer.

System sabotage means changing critical configurations of your network, preventing your systems from operating normally. Insiders can pull off a lot of other risky actions including:

• Modifying critical configurations of your systems
• Preventing your systems from operating normally
• Installing malware
• Creating backdoors for outside attackers, and more.

In short, if there’s an ongoing insider attack in your company, all your valuable IT assets are in danger: networks, file servers, cloud storage, databases, and even endpoints. There are also a number of risk factors that can increase the possibility of insider attacks. The most common and critical are:

• Excessive access privileges. When too many people gain access to the most critical assets, it creates an additional risk for data misuse or compromise. That’s why it is recommended to implement the principle of least privilege within your organization. 
• Shadow IT. When employees install software that wasn’t approved and isn’t managed by your IT department, it creates additional shadow IT security risks for malware being installed. In addition, unapproved software may be incompatible with other software used in your company, harming the operation of your systems. To minimize threats associated with shadow IT, follow the best practices for mitigating risks coming from the use of shadow IT.
• Bring Your Own Device (BYOD) policies. When employees use personal devices for corporate purposes, it creates additional cybersecurity risks. Consider monitoring user-owned devices to reduce those risks. It’s possible to track user sessions on BYO-PCs, while still allowing for user privacy.

Detecting and mitigating an insider threat in a timely manner should be a top priority for any cybersecurity officer and business owner. In the next section, we talk about the common indicators of insider threats and the most effective ways of mitigating the risks of insider threats.

Handling an insider threat: proactive vs. reactive methods

There are two basic scenarios for dealing with an insider attack: proactive response, i.e. trying to prevent an attack from happening in the first place, or reactive response, i.e. addressing it efficiently and in a timely manner. Of course, to get the best possible results, it’s best to create an insider threat program that combines both approaches. Thus, develop and document in your insider threat program security measures that will address these aspects:

• Insider attack prevention – Build up your cybersecurity policy and an insider risk management process in a way that allows you to keep the risk of insider attacks as low as possible.
• Detection and response – Create an insider threat detection program that allows you to detect an attack in its early stages and build an efficient incident response plan in order to limit possible damage.

You can detect a potential insider threat by watching out for various indicators of suspicious behavior:

How can you prevent an insider attack?

There are many insider threat detection and prevention platforms on the market that help organizations enhance their cybersecurity and mitigate insider threats. The essential purpose of these platforms is to monitor employee activity and send alerts of potential threats to the appropriate personnel within your organization.

Depending on a business’s need, this type of software can collect various data, including:

• Online activity — visited websites, email exchanges, downloaded and uploaded files and applications, and online search history.
• General activity — manipulation of files and data, launched applications, connected USB devices.

In addition to leveraging insider threat detection and prevention software, you can take the following steps to minimize the risk of insider threats:

Cybersecurity policies and guidelines. Having detailed and thoroughly planned cybersecurity policies and guidelines is the first step toward securing your valuable assets.

Your employees should know exactly:

• What the allowed scenarios for working with sensitive information are.
• What they should do in case of a cybersecurity incident.
• What the rules for working with corporate systems are.

All this information should be included in your cybersecurity policy and smaller department and role-specific guides.

Access management. The best way to prevent employees from misusing their access privileges is to grant them only the permissions they really need. Role-based access control and just-in-time PAM are perfect ways to ensure the required level of access granularity. These approaches can also help you limit the scope of allowed operations for each role to a secure minimum.

Multi-factor authentication (MFA) is a commonly acknowledged best practice for securing valuable assets and effectively managing access to them. Another possible approach is implementing a zero trust security model when access to a critical asset is always limited and always requires additional approval or user identity verification.

Technical controls. Since data is usually one of the main targets of cybercriminals, you need to make it harder to tamper with your critical data. For instance, regular data backups and the deployment of data loss prevention tools can limit the risks associated with the damage or loss of valuable information.

USB management tools. These come in handy for preventing your employees from using unauthorized USB devices to install malware or copy company data for personal use.

However, it’s important to clarify that preventive measures only help minimize the risk of an insider attack. To defend your company against cybersecurity threats, you need to thoroughly plan ways to detect and respond to insider attacks.

How to detect insider threats and respond to them?

Just as with prevention, there are a number of key factors affecting your ability to effectively detect and respond to insider threats. 

User activity monitoring. Having full visibility across your network is one of the most effective practices for detecting and preventing insider fraud incidents and other insider threats. And the best way to achieve the required level of visibility across your network is by monitoring all activity within your network 24/7.

Start with monitoring employee activity. You need to know who does what, when, and how. You can start with monitoring privileged accounts and critical assets, and then expand the scope of monitored users and sessions as needed.

Next, you need to pay special attention to monitoring and auditing your subcontractors. As they may have legitimate access to your critical assets, you must make sure they aren’t misusing their access privileges.

Logging and auditing. Simple monitoring won’t be enough to secure your valuable assets. It’s important that your monitoring solutions gather and log data about monitored sessions and users.

In addition, you must be able to audit and analyze gathered data; otherwise, you won’t be able to act on it. So make sure your activity monitoring solution allows you to form detailed reports for further auditing.

Incident detection and response. The longer an attack remains undetected, the more it will cost to remediate. In order to detect an insider attack as soon as possible, you need to create a comprehensive incident response system. There are a number of features that you may find useful for building such a system, including:

• Alerts and notifications. Setting alerts for specific events such as the creation of a new privileged account or deletion of a particular set of data will help you detect suspicious actions and take proper actions in the early stages of a potential attack. 
• Automatic response. Being able to block a process, application, or user that acts suspiciously or violates security rules can help you limit the potential damage caused by a cybersecurity incident.

User and entity behavior analytics (UEBA). In order to combine the benefits of user activity monitoring and active incident response, consider implementing a UEBA solution. UEBA solutions gather information on both human and non-human entities, analyze their behavior, and build a baseline profile for each. When the activity of a monitored entity deviates from the defined baseline, UEBA can alert you to a possible insider attack.

The biggest advantage of such an approach is that all data is processed by an artificial intelligence algorithm, not a human. Algorithms can analyze data more precisely and detect suspicious patterns a human analyst may miss.

Employee education. It’s also crucial to educate your employees and third-party partners on your organization’s cybersecurity policies as well as cybersecurity best practices in general. Make sure that your employees and contractors are aware of insider threats and how to report them. When they know the specific indicators of insider threats, they can pick up on suspicious activity — sometimes even before software detects it.

Deter, detect, and disrupt insider threats with Syteca

Syteca is a comprehensive insider risk management platform that can help you prevent, detect, and swiftly respond to insider threats, focusing on the three core goals:

1. Deter potential insider threats. Syteca lets you implement granular access management for both privileged and general user accounts. You can also set two-factor authentication for enhanced identity management. 
2. Detect abnormal activity. Syteca allows your security team to log all user sessions and monitor user activity in real-time or with recordings. The platform also detects potential insider threats thanks to a built-in UEBA module and highly configurable real-time alerts.
3. Disrupt malicious actions. Syteca provides your security officers with real-time notifications and contextual information so they can immediately identify and disrupt any potential insider threats. They can warn a user, block the session, or immediately kill the process that triggers an alert. In addition, Syteca lets you investigate security incidents thanks to its advanced auditing and reporting functionality. Moreover, you can export encrypted data from sessions or their fragments for further forensic investigations.

Conclusion

Insiders can pose a significant threat to your organization. To mitigate insider risks, you should create effective policies for prevention, detection, and incident response, and back them up with dedicated insider threat management software. As a comprehensive insider risk management platform, Syteca allows you to minimize the risk of insider threats by monitoring and auditing user activity, managing access, and responding to cybersecurity incidents in a timely and efficient manner.