The Enemy Within: Strategies to Mitigate Insider Threats in Business Networks

You might run endless social engineering attacks to create a strong security culture and mitigate any risks to your company. Yet, you might still be easily exposed and get your data stolen. That’s how dangerous a malicious insider activity is…

Fortunately, if you know what you’re doing, you can prevent this and keep your security in check.

And that’s what you’re about to discover. In this post, you’ll discover how to spot and eliminate insider threats, so you can protect your reputation and customer’s sensitive data.

What Are Insider Threats?

Insider threats encompass security risks originating from individuals within an organization, such as:

  • Employees
  • Contractors
  • Business associates

These people, whether intentional or unintentional, can compromise your security, posing substantial risks to confidentiality, integrity, and overall operational stability. Insider threat incidents may manifest in diverse forms like data breaches, intellectual property theft, or malware introduction.

Why Are Insider Attacks So Dangerous?

Insider attacks pose a danger due to their covert nature, exploiting the trust and access. 

Unlike external threats that face barriers such as firewalls and intrusion detection systems, insiders operate within the organization’s trusted environment — making it potentially challenging to identify. That’s right, insiders can leverage their intimate knowledge of the organization to inflict harm. 

4 Types of Insider Threats

Let’s explore four insider threat types, and why enterprises must take proactive measures to prevent them:

1. Malicious Insiders

Individuals classified as malicious insiders deliberately act against an organization’s interests. 

These employees seek revenge, are motivated by financial gain, or just coerced into betraying the organization. Their actions, such as stealing sensitive data, unauthorized access, or intentionally causing system damage, pose a severe threat to the organization’s security and integrity.

2. Negligent Insiders

Negligent insiders contribute to security risks unintentionally through careless actions or oversights. 

This involves mishandling sensitive information, not adhering to security protocols, or inadvertently exposing critical data. Despite lacking malicious intent, their actions can impact cybersecurity. Mitigating unintentional insider threat activity becomes crucial through comprehensive training and awareness programs.

3. Compromised Insiders

Compromised insiders have had their credentials or access exploited by external malicious actors. 

This insider incident arises when an employee’s login credentials are stolen, either through phishing attacks or other means. This allows unauthorized individuals to impersonate legitimate insiders — infiltrating the organization’s systems, accessing sensitive data, or conducting malicious activities from within.

4. Unintentional Insiders

Accidental insiders unknowingly contribute to security risks. 

Actions may include falling victim to phishing scams, using weak passwords, or connecting unsecured devices to the corporate network. Despite their non-malicious intentions, the inadvertent compromise of security underscores the need for robust Insider Threat programs.

How to Fight Insider Threats: 10 Mitigation Best Practices

Below are our ten best practices to effectively mitigate the risks posed by insiders, for maximum threat protection:

1. Enhance Employee Security Awareness

Creating a culture of security within your organization is crucial.

Introduce comprehensive training programs, so employees can learn to recognize and prevent insider threats. These initiatives should cover:

  • How to spot suspicious behavior (Insider threat indicators)
  • The importance of following security policies

This will make every employee a great defender against potential breaches and security risks within your business.

2. Utilize User Behavior Analytics

User Behavior Analytics (UBA) tools are powerful in monitoring user activities and identifying anomalies that could indicate insider threats. By analyzing patterns and detecting deviations, you can pinpoint unusual behavior that might otherwise go unnoticed — providing an early warning system for potential security issues.

3. Strengthen Access Security Control and Monitoring

Implement strict access controls, so employees have insider access only to the information they need.

Monitoring privileged user activities further secures sensitive information which nicely reduces the risk of unauthorized access and potential insider threats.

4. Tailor Incident Response Planning

A well-prepared incident response plan specifically designed to address insider threats is essential.

This plan should detail how to respond quickly and effectively to security incidents — minimizing potential damage and ensuring recovery with minimal disruption.

5. Conduct Regular Audits and Compliance Checks

Routine audits are vital for maintaining security hygiene.

By regularly reviewing user permissions and ensuring they align with current job responsibilities, you prevent excessive access privileges. Compliance checks are equally important to ensure that you meet all regulatory requirements — protecting you against legal and financial repercussions.

6. Implement Data Encryption Measures

Encrypting sensitive data is a key security measure.

Encryption ensures that even if data is accessed by unauthorized individuals, it remains unreadable and secure. This safeguards information from potential insider threats.

7. Adopt the Least Privilege Principle

The principle of least privilege restricts access rights for users to the bare minimum.

(You only have permissions necessary for completing your tasks.)

This approach minimizes the risk of accidental or deliberate misuse of access, significantly enhancing the security posture of the organization.

8. Deploy Continuous Monitoring Solutions

Continuous monitoring solutions provide real-time surveillance of network activities.

This enables you to detect and respond to suspicious activity swiftly. This vigilance is crucial for identifying potential threats before they can escalate into serious breaches.

9. Invest in Insider Threat Detection Software

Specialized software can effectively identify patterns of behavior indicative of insider threats.

Investing in such technology allows you to detect risks more accurately — enhancing the ability to protect against potential internal security breaches.

10. Encourage Cross-Department Collaboration

A collaborative approach among HR, IT, and security teams can lead to more effective identification and management of insider threats. Sharing insights and information across departments ensures a unified and comprehensive strategy.

(Leading to a solid strategy for safeguarding the organization against potential internal risks.)

Supercharge Cybersecurity with Perimeter 81

Embracing a holistic approach that combines technological solutions with cross-departmental collaboration can enhance resilience to insider threats and keep your data secured.

That way, you can prevent any of these issues:

  • Reputational damage
  • Putting critical assets at risk
  • Risk of insider threats and harm

Not sure how to get started?

Book a FREE demo with Perimeter81’s security experts, put a solid insider threat strategy in place, and prevent threats or vulnerabilities right now.


What is the most effective strategy for protecting against an insider threat?
The most effective strategy is for organizations to conduct a simulated phishing exercise, specifically targeting users who struggle to identify phishing attempts. This proactive approach aims to minimize the potential for employees and contractors to inadvertently become compromised insiders. Additionally, encouraging a culture of awareness goes a long way in preventing insider threats. Employees should be trained to identify and report suspicious behavior among their colleagues, providing an anonymous avenue to alert HR or IT security. This collaborative effort can effectively preempt malicious insider threats, particularly those stemming from disgruntled employees.
Which are the two most popular technologies to deter insider attacks?
Utilizing technology is crucial in mitigating insider threats, with user and entity behavior analytics (UEBA) and data loss prevention (DLP) standing out as key solutions. UEBA centers on monitoring and analyzing user behavior within an organization to detect any malicious or unauthorized activities. 
What is the first line of defense for insider attacks?
Employing network firewalls to segment the network acts as a first line of defense, enhances internal traffic visibility and adds complexity for attackers or malicious insiders attempting lateral movement within an organization’s network.