What are Insider Threats? Types, Prevention & Risks

We break down insider threat definitions with our guide. Learn about different insider threat types, examples, tactics, and much more. Address your organization’s biggest risks and get secured.

Insider threats refer to risks posed by individuals within an organization. This guide explores the types of insider threats, their potential impacts, and strategies for prevention.

Learn about the importance of employee awareness and monitoring in mitigating insider risks. Understanding insider threats is crucial for organizations to protect sensitive information and maintain security.

What are Insider Threats?

Insider threats are a type of cyber attack that come from individuals who work within an organization. These individuals have authorized access to files, networks, and systems, They may be your current employee, board members, business partners, or even consultants who work with the organization.

An insider will use his/her authorized access to:

• Harm the organization by leaking their data, resources, or damage the business reputation. 
• They can corrupt or degrade data, sabotage company assets, and spread ill or false info
• Insiders may conduct cyber espionage, or disclose sensitive information to parties who do not belong to the organization.

Types of Insider Threats

Insider threats can take many forms, and they are not always malicious. In some cases, employees may inadvertently cause a security breach by clicking on a phishing email or using a weak password. In other cases, employees may intentionally cause harm for financial gain, revenge, or to obtain sensitive information.

There are three main categories of insider threats:

• Careless or Unintentional Threats – These types of insider threats occur when an employee or contractor unintentionally causes a security breach. This can happen through a lack of awareness or training or simply by making a mistake.
• Malicious Insider Threats – Malicious insider threats occur when an employee or contractor intentionally causes harm to the organization. This can be for financial gain, revenge, or to obtain sensitive information.
• Compromised Insider Threats – A compromised insider threat occurs when an attacker gains access to an employee’s or contractor’s account or system and uses it to carry out an attack. This can happen through phishing attacks, social engineering, or other means.

Insider Threats Key Indicators

You will know that an insider threat is lurking when your systems get hacked. You get logins at unusual times and your data usage becomes higher across devices. Here are some ways to spot indicators of insider threats:

• Do backdoor file scans - Check your system and look for incoming external requests. These are hackers who are trying to locate and use backdoors in your organization.
• Look for Remote Access Instances - Any hardware or software like TeamViewer being used for malicious purposes, monitor their activity. Check for any physical servers around too like Synology devices.
• Changing passwords  - If your passwords are being changed too frequently or old ones suddenly don't work, then that is an insider attack incoming. See who has access rights, how much, and to what assets.
• Unauthorized changes to antivirus and firewalls - If your antivirus and firewall settings change, then that can be the result of an insider attack.  If you get any new malware, investigate its source immediately and resolve it before it escalates.
• Extra access attempts  - If you get too many access attempts to sensitive areas in your network, then that's probably someone trying to exfiltrate data to outside the organization. Look into them and start questioning their activity.

Real-World Examples of Insider Threats

Several high-profile insider threat cases have made headlines in recent years. For example, the data breach at Equifax in 2017 was caused by an insider who exploited a vulnerability in the company’s web application to steal the sensitive data of 143 million customers. Another example is the case of Edward Snowden, who leaked classified information from the National Security Agency (NSA) in 2013.

Preventing Insider Threats

Preventing insider threats requires a multi-layered approach that involves people, processes, and technology. Here are some practical steps organizations can take to protect themselves from insider threats:

• Educate employees – Provide regular security awareness training to employees, contractors, and third-party vendors.
• Implement access controls – Limit access to sensitive data based on the principle of least privilege. Use two-factor authentication, role-based access control, and other access control mechanisms.
• Monitor and audit user activity – Implement logging and monitoring solutions to detect anomalous behavior and identify potential insider threats.
• Enforce security policies – Have clear security policies and enforce them rigorously.

How To Stop Insider Threats

There are some additional steps you can also take to prevent insider attacks. Here is what else you can do to reduce the risk of insider threats:

• Make use of UEBA tools - User behavior and entity monitoring security tools can create baselines for employee activity. They trigger alerts based on anomalous behaviors automatically, like unauthorized data transfers, off-hours access, unusual file downloads, etc.
• Enforce Multi-factor Authentication - Don't be limited to single or two authentication factors. Use a mix of facial recognition, OTPs, biometrics, and others to prevent compromised account usage.
• Conduct Regular Employee Screenings - It doesn't matter if they're new, currently working, or on the verge of quitting. Make this mandatory and regular. Build a comprehensive employee offboarding program as well for your business. Do routine audits and segregate duties to reduce the chances of fraud being committed in the organization.

Why Are Insider Threats Significant?

Insider threats can be particularly harmful to organizations because insiders already have access to sensitive data and systems. This means they do not need to bypass any security controls to cause harm, making them a more challenging threat to detect and prevent.

Moreover, insiders can cause significant damage to an organization’s reputation, financial stability, and legal standing. For example, insiders who steal intellectual property or sensitive customer information can damage an organization’s reputation and credibility. Insiders who disrupt network operations can cause significant financial losses and impact an organization’s ability to provide customer services.

In addition, insider threats are becoming more prevalent and sophisticated, making it challenging for organizations to keep up. According to Gurucul’s 2023 Insider Threat report, in 2022, there was a significant increase in insider attacks as 74% of organizations report that attacks have become more frequent (a 6% increase over last year), with 60% experiencing at least one attack and 25% experiencing more than six attacks.

How to Protect against Insider Threats

If you want to protect your organization from insider attacks, you need clarity on what you’re dealing with. Follow these guidelines to focus on your assets, people, and tools accordingly:

Protect Critical Assets

Start by identifying what matters most. Pinpoint key systems, sensitive data, physical locations, and personnel. Rank these assets by importance. Then, apply your strongest security measures to the highest-priority items. This focused approach ensures your most valuable resources get the most protection.

Create a Baseline of Normal Behavior

You need to know what normal looks like to spot what is not. Use software to track user and device activity. Pull data from access logs, VPN connections, and authentication systems. Build a pattern of typical behavior for each user and job role. This baseline lets you flag anomalies, like a user downloading large files at unusual hours, for quick review.

Increase visibility

Deploy monitoring tools that watch user actions and link data from different sources. You could use deception technology, like setting traps for malicious insiders. These traps can reveal their methods and goals. Feed this intelligence into your other security systems to block attacks.

Enforce policies

Define your security rules. Document them and share them with everyone. Employees, contractors, and partners must understand acceptable behavior. Remove any ambiguity. Make it clear that sharing privileged information without authorization is not allowed.

Promote culture changes

Stopping a threat is better than detecting it. Work to discourage harmful actions before they happen. Build a culture where security is a shared responsibility. Regular training helps. So does measuring employee satisfaction to catch early signs of discontent that could lead to risk.

How To Address the Risk of Insider Threats

1. Develop a comprehensive insider threat program – To address insider threats; organizations should develop a comprehensive program that includes policies, procedures, and technologies. This program should cover all aspects of insider risk, including employee monitoring, access control, and incident response.
2. Conduct regular security awareness training – Regular security awareness training can help employees understand the risks of insider threats and how to avoid them. Employees should be trained on best practices for password management, social engineering attacks, and how to report suspicious activities.
3. Monitor employee activities – Monitoring employee activities is critical to detecting and preventing insider threats. This can include monitoring employee emails, file transfers, and network activity. However, organizations must balance the need for monitoring with employees’ privacy rights and legal requirements.
4. Implement access controls – Access controls can help limit the exposure of sensitive data and systems to insiders. Organizations should implement role-based access controls, ensuring employees have access only to the data and systems necessary to perform their job duties. Access controls should also be regularly reviewed and updated to remain effective.
5. Use XDR and anti-malware software – XDR (Extended Detection and Response) is a next-generation security technology that provides real-time threat detection and response across multiple vectors, including endpoints, networks, and cloud environments. Anti-malware software can help detect and prevent malicious software from being installed on employees’ devices. With XDR, enterprises can identify abnormal access and user behavior, enabling the detection of such attemp.ts
6. Conduct background checks – Organizations should conduct thorough background checks on employees, contractors, and third-party partners before granting them access to sensitive data and systems. Background checks can help identify potential insider threats, such as individuals with a history of theft or fraud.
7. Implement incident response procedures – Organizations should have incident response procedures to respond quickly and effectively to insider threats. These procedures should include steps for reporting and investigating incidents, identifying the root cause of the incident, and implementing corrective actions to prevent similar incidents from occurring in the future.

Conclusion

Insider threats are a significant and growing risk for organizations of all sizes and industries. Insiders accessing an organization’s sensitive data and systems can cause significant harm, intentionally or unintentionally. Given the potential impact of insider threats, organizations must take steps to mitigate this risk.

A comprehensive insider threat program that includes policies, procedures, and technologies to detect and prevent insider threats is critical. Organizations should also conduct regular security awareness training, monitor employee activities, implement access controls, use encryption and DLP technologies, conduct background checks, and implement incident response procedures.

By taking these steps, organizations can reduce the risk of insider threats and protect their sensitive data, systems, and reputation. Remember, the best defense against insider threats is a proactive and comprehensive approach that involves all levels of the organization, from the executive team to the front-line employees.

Insider Threat FAQs

What is an Insider Threat?

An insider threat is a security risk originating from within an organization—typically by someone with legitimate access, like an employee or contractor, who misuses credentials or privileges. This can include stealing data, sabotaging systems, or leaking sensitive information.

Insider risks may be intentional (malicious) or unintentional (negligence), but either way they exploit trusted access and can harm operations, finances, or reputation.

What best describes an insider threat?

An insider threat is best described as a person inside your organization who uses their authorized access to cause damage. They might steal sensitive data for personal gain or sabotage systems because they feel disgruntled. 

Their actions can also be careless, like accidentally leaking information through poor security habits.

What Types of Insider Threats exist?

The main types of insider threats are:

• Malicious insiders who deliberately steal or sabotage data for personal gain or revenge.
• Negligent insiders who accidentally expose data or introduce risks through careless actions, like misconfiguring systems.
• Inadvertent insiders unintentionally compromise security, often by falling for phishing scams or mishandling sensitive information.

Why are Insider Threats so Difficult to Detect?

Insiders operate with valid credentials and knowledge of internal policies, so their actions often blend in with normal activity. Security tools focus on external attacks and may not flag legitimate logins or routine tasks. Moreover, insiders know which controls to bypass and can cover their tracks, extending dwell time before detection.

What are Common Indicators of Insider Risk?

Look for unusual patterns in data access (large downloads at odd hours), repeated failed login attempts, copying sensitive files to external drives, unexpected privilege escalations, and deviations from normal work behavior. Sudden changes in email or network activity—like sending confidential documents outside approved channels—also signal insider risk.

What is the Average Cost and Detection Time for Insider Threats?

According to Ponemon’s 2025 Cost of Insider Risks Report, the average annual cost per insider incident reached $17.4 million, up from $16.2 million in 2023. At the same time, the mean time to contain such an incident fell to 81 days, down from 86 days the previous year.

What are the key risks caused by an insider threat?

The key risks are data theft, financial fraud, and sabotage of critical systems. Insiders can destroy or corrupt data, leading to major operational downtime. 

They can also leak intellectual property to competitors, which can cause long-term damage to your business's competitive advantage and reputation.

How do Insider Threat Programs Work?

Programs combine policy, people, and technology. They start with risk assessments and clear policies on data access. Continuous monitoring tools flag suspicious behavior, which a dedicated team investigates. Regular training raises awareness, while incident response plans ensure quick containment. Feedback loops refine rules and improve detection over time.

Which Industries are most vulnerable to Insider Threats?

Financial services face the highest insider-related costs—averaging $14.5 million annually—due to valuable data and complex systems. Healthcare follows with costly patient data breaches. Government agencies and energy/utilities also rank high, given critical infrastructure and regulatory fines for data loss.