What Is an Insider Threat?

An insider threat can happen when someone close to an organisation with authorised access misuses that access to negatively impact the organisation’s critical information or systems. This person does not necessarily need to be an employee—third-party vendors, contractors, and partners could also pose a threat. Insider threats can be unintentional or malicious, depending on the threat’s intent. Unintentional insider threats can arise from a negligent employee falling victim to a phishing attack. Examples of malicious threats include intentional data theft, corporate espionage, or data destruction.

Your biggest asset is also your biggest risk and the root cause of insider threats: people. Yet most security tools only analyse computer, network, or system data.

Threats can come from any organisational level and from anyone with access to proprietary data. In fact, 25% of all security incidents involve insiders.^[1]

Recent insider threat statistics reveal that 69% of respondents say their organisations have experienced an attempted or successful threat or corruption of data in the last 12 months.

An insider is a current or former employee, contractor, or business partner who has or has had authorised access to the organisation’s network, systems, or data. Examples of an insider may include:

• A person given a badge or access device.
• A person to whom the organisation supplied a computer or network access.
• A person who develops products and services.
• A person who is knowledgeable about the organisation’s fundamentals.
• A person with access to protected information.

Insider threats pose a significant risk to organisations, as they often involve individuals with authorised access who misuse that access to harm the organisation’s critical information or systems. To effectively detect and mitigate insider threats, understanding the behaviour patterns and technical indicators associated with them is essential.

Behaviour Patterns

Sophisticated intrusion detection systems and monitoring applications analyse network traffic and user behaviour patterns to identify potential insider threats. Some common behaviour patterns associated with insider threats include:

• Frequently violates data protection and compliance rules.
• In constant conflict with other employees.
• Consistently receives low-performance reports.
• Uninterested in projects or other job-related assignments.
• Misuses travel and expenses.
• Interested in other projects that don’t involve them.
• Uses sick leave frequently.

These behaviour patterns can indicate malicious intent or negligence on the part of the insider.

Technical Indicators

In addition to behaviour patterns, technical indicators can help detect insider threats and data theft. Some common technical indicators include:

• Unusual data movement: Excessive spikes in data downloads, sending large amounts of data outside the company, and using tools like Airdrop to transfer files can be signs of an insider threat.
• Use of unsanctioned software and hardware: Negligent or malicious insiders may install unapproved tools to simplify data exfiltration or bypass security controls. This “shadow IT” creates security gaps.
• Increased requests for escalated privileges or permissions: When an increasing number of people request access to sensitive information, it raises the risk of insider threats, whether from malicious intent or accidental exposure.
• Access to information unrelated to their job function: If an employee attempts to access data not pertinent to their role, it could be a sign of an insider threat.
• Renamed files where the file extension doesn’t match the content: Malicious insiders may try to mask data exfiltration by renaming files to hide their actual content.
• Abnormal access times outside regular business hours: Unusually timed logins and activity at odd hours can help detect potential insider threats.
• Unusual logon activity accessing credentials such as multiple sessions: Suspicious credential usage patterns can indicate an insider threat. Additionally, changing passwords can also signal unusual activity.
• Unknown locations accessing resources: Logins from unfamiliar locations may signal an insider threat.

These technical indicators can be used with behaviour patterns to identify potential insider threats and mitigate the associated risks. By understanding and monitoring these behaviour patterns and technical indicators, organisations can better detect and respond to insider threats, ultimately safeguarding their critical information and systems.

An insider is anyone within your organisation’s network. Most organisations understand this to mean that an insider is an employee, but insider threats can also come from third parties.

Insiders include:

• High-privileged users such as network administrators, executives, partners, and other users with permissions across sensitive data.
• Developers with access to data using a development or staging environment.
• Resigned or terminated employees with enabled profiles and credentials.
• Acquisition managers and employees.
• Vendors with internal access.
• Contractors with internal access.
• Partners with internal access.

• One-third of all organisations have faced an insider threat incident.^[2]
• 50% of incidents where private or sensitive information was unintentionally exposed.^[3]
• 40% of incidents where employee records were compromised or stolen.^[3]
• 33% of incidents where customer records were compromised or stolen.^[3]
• 32% of incidents where confidential records (trade secrets or intellectual property) were compromised or stolen.^[3]

Every organisation is at risk of insider threats, but specific industries obtain and store more sensitive data. These organisations are more at risk of hefty fines and significant brand damage after theft. Larger organisations risk losing large quantities of data that could be sold off on darknet markets. An insider threat could sell intellectual property, trade secrets, customer data, employee information and more. Industries that store more valuable information are at a higher risk of becoming victims.

A few common industries at high risk of insider threats include:

• Financial Services
• Telecommunications
• Technical Services
• Healthcare
• Government

Insider threats—employees or users with legitimate access to data—are difficult to detect. These threats have the advantage of legitimate access, so they do not need to bypass firewalls, access policies, and cybersecurity infrastructure to gain access to data and steal it.

Malicious, high-privilege users can cause the most devastating insider attacks by stealing data with minimal detection. Keep in mind that these users are not always employees. They can be vendors, contractors, partners, and other users with high-level access across all sensitive data.

Corporations spend thousands to build infrastructure to detect and block external threats. These threats are not considered insiders even if they bypass cybersecurity blocks and access internal network data. Insider threats are specific trusted users with legitimate access to the internal network. They have legitimate credentials, and administrators provide them with access policies to work with necessary data. These users do not need sophisticated malware or tools to access data because they are trusted employees, vendors, contractors, and executives.

Any attack that originates from an untrusted, external, and unknown source is not considered an insider threat. Insider threats require sophisticated monitoring and logging tools so that any suspicious traffic behaviours can be detected. Older, traditional ways of managing users were to blindly trust them, but a zero-trust network is the latest cybersecurity strategy, along with data loss prevention (DLP) solutions. These frameworks require administrators and policy creators to consider all users and internal applications as potential threats.

An external threat is typically motivated financially to steal data, extort money, and potentially sell stolen data on darknet markets. While insider threats could share this motivation, it’s more likely that an insider will unintentionally fall for a sophisticated phishing or social engineering attack. In the case of a malicious threat actor, a common goal is to harm the organisation by data theft.

Insider threats come in many forms, making the warning signs difficult to identify. The most common underlying characteristics of modern insider threats include:

• Authorised access: An insider threat is someone with legitimate access to an organisation’s systems, data, or facilities, such as an employee, contractor, vendor, or partner.
• Malicious intent or negligence: Insider threats can be malicious, where the individual intentionally misuses their access to harm the organisation, or negligent, where the individual unintentionally exposes the organisation to risk through careless actions.
• Difficult to detect: Insider threats are challenging to detect because the individual already has authorised access, making it hard for security controls to distinguish normal from harmful activity.
• Strong motivation: Malicious insiders often have a strong personal motive, such as revenge, financial gain, or espionage, that drives them to misuse their access.
• Varied tactics: Insider threats can employ a range of tactics, from data exfiltration and sabotage to credential theft and privilege escalation, to achieve their goals.
• Increased risk in certain industries: Sectors like healthcare, finance, manufacturing, and government are at heightened risk of insider threats due to the sensitive nature of their data and operations.

Because users generally have legitimate access to files and data, good insider threat detection looks for unusual behaviour and access requests and compares this behaviour with benchmarked statistics.

Even the most successful and reputable companies are not immune to inside threats. Here are real-world examples of insider threats that have led to significant cybersecurity breaches:

• Desjardins: In 2019, Canada’s largest credit union required users to copy customer data to a shared drive that everyone could use. A malicious insider continued to copy this data for two years, resulting in 9.7 million publicly disclosed customer records. It cost Desjardins $108 million to mitigate the breach.
• General Electric: An engineer at General Electric, Jean Patrice Delia, stole over 8,000 sensitive files to start a rival company. The FBI investigated this incident, and Delia was sentenced to up to 87 months in prison.
• Tesla: Two former Tesla employees misappropriated confidential information, including personal information of employees and production secrets, which was then leaked to a German news outlet.
• SunTrust Bank: A former SunTrust employee stole 1.5 million names, addresses, phone numbers, and account balances for bank customers. Other sensitive data was not accessed, but it posed a risk to the bank and its customers.
• Coca-Cola: An investigator found that a Coca-Cola employee copied the data of about 8,000 employees to a personal external hard drive. After Coca-Cola became aware of the data breach, the organisation notified employees and offered free credit monitoring for a year.
• Pegasus Airlines: An employee’s negligence at Pegasus Airlines led to the exposure of 23 million files containing personal data due to improper configuration of an AWS bucket. This incident exposed flight charts, navigation materials, and crew personal information.
• Cash App: A disgruntled employee leaked Cash App’s customer data. This case highlights the risk posed by employees who may act maliciously due to dissatisfaction or other personal motives.

Inside threats are a much different beast to tame. Organisations with an exceptional cybersecurity posture can still encounter data leaks and breaches with potentially catastrophic outcomes. Although challenging, recognising indicators and detecting insider threats is critical for organisations with many employees, vendors, and contractors who have access to internal data.

Insider threats come from within and are as diverse in their origins as they are in their intentions and methodologies. Here’s a structured breakdown of these varied types:

• Malicious insider threats: Characterised by individuals with authorised access who deliberately seek to harm the organisation. These insiders might sell sensitive data to rivals, leak confidential information intentionally, or engage in direct sabotage against company systems.
• Opportunistic insider threats: Stemming from employees without initial malintent but who become seduced by opportunity. They may hoard sensitive information during their tenure and choose to exploit it upon departure or at another opportune moment for personal gain or vendetta.
• Negligent insider threats: These actions inadvertently compromise security through disregard for protocols. Employees seeking shortcuts might bypass essential safeguards, unintentionally exposing critical assets without malicious intent.
• Accidental insider threats: Purely unintended incidents where insiders cause data breaches through mistakes—like sending files to incorrect recipients or misconfiguring databases—highlighting human error without any underlying motive.
• Compromised insider threats: Occur when external entities hijack legitimate users’ credentials via phishing scams or malware, thus gaining unauthorised access while masquerading as genuine employees—a deceitful breach executed under false pretences.
• Collusive threats: These threats emerge when insiders collaborate with external entities, such as competitors or cyber criminals, to conduct espionage, intellectual property theft, or facilitate unauthorised access. This collusion can significantly amplify the potential damage by combining insider knowledge with external resources and capabilities.

Understanding these diverse categories of insider threats underscores the imperative for a holistic approach to cybersecurity—one that transcends mere technological fixes and incident response plans. It highlights the critical role of fostering an organisational culture steeped in security awareness and vigilance at all levels.

Organisations must implement comprehensive strategies to detect and mitigate malicious insider threats, which can cause significant damage to the organisation’s data and reputation. Here are some techniques and tools that can help in detecting and preventing malicious insider threats:

• Behavioural analytics: These tools analyse user behaviour patterns to identify anomalies and detect potential insider threats. They can detect if an employee is suddenly accessing unusual files or systems, which may indicate malicious intent.
• Data loss prevention: DLP solutions monitor and protect sensitive data by identifying and preventing unauthorised access, transfer, or data leakage. They can help organisations enforce access controls and monitor data movements.
• Cybersecurity analytics and monitoring solutions: Cybersecurity analytics solutions that send alerts and notifications when users display suspicious activity to help organisations detect and respond to potential insider threats. These solutions also provide real-time visibility into user activities and data movements.
• User behaviour analytics: UEBA tools analyse user behaviour patterns to identify anomalies and detect potential insider threats. They can detect if an employee is suddenly accessing unusual files or systems, which may indicate malicious intent.
• Machine learning: ML models can be trained to identify insider threats by analysing patterns of behaviour associated with insider attacks. These models can help organisations detect and respond to potential threats more effectively.
• Threat hunting: Proactive threat hunting involves hunting for anomalous insider behaviour that may not be detected by security controls alone. This can be done using techniques such as UEBA, ML, and human intelligence to identify potential threats.
• Insider threat management and security solutions: ITM software can help organisations detect and respond to insider threats by monitoring user activities and data movements, identifying abnormal behaviour patterns, and automating responses to potential security incidents.
• Real-time monitoring: Tracking user activity and data movements in real-time can help organisations detect and respond to potential insider threats more effectively. This can be achieved using solutions that offer customisable alert thresholds to minimise false positives and real-time threat review capabilities.
• User feedback learning: Integrating user feedback to refine anomaly detection models can help organisations tailor their threat detection systems to specific organisational needs, improving the accuracy of their insider threat detection efforts.
• Kill chain detection: Employing cyber kill chain detection can help organisations uncover lateral malware movement or insider threat activities, identifying irregular behaviours and command-and-control (C&C) communication.

By implementing these techniques and tools, organisations can improve their ability to detect and respond to malicious insider threats, ultimately reducing the risk of data loss and system compromise.

Insiders are some of the most challenging threats to pinpoint and prevent, requiring a multifaceted approach. To effectively stop insider threats, organisations should implement a comprehensive security strategy that includes a combination of the following best practices and tools:

• Establish a security policy: Assemble a proactive security policy that includes procedures for detecting and blocking misuse by insiders. Consider including the consequences of potential insider threat activity and outline guidelines for investigating misuse.
• Implement a threat detection governance programme: Establish an ongoing, proactive threat detection programme in collaboration with your leadership team. Ensure executives and key stakeholders are well informed on the scope of malicious code reviews, with privileged users treated as potential threats.
• Secure your infrastructure: Restrict physical and logical access to critical infrastructure and sensitive information using strict access controls. Apply least privileged access policies to limit employee access and apply more robust identity verification systems to reduce the risk of insider threats.
• Map your exposure: Your organisation’s CISO should analyse your internal teams and map each employee’s likelihood of becoming a threat. This analysis shines a spotlight on potential risks and areas for improvement.
• Use threat modelling: Apply threat modelling at a large scale to better understand your threat landscape, including threat vectors related to malicious code or vulnerabilities. Identify the type of roles that might compromise a system and how they might access your assets.
• Set up strong authentication measures: Use multifactor authentication (MFA) and safe password practices to make it harder for attackers to steal credentials. Passwords should be complex and unique, and MFA helps prevent infiltrators from accessing your system even if they have user IDs and passwords.
• Prevent data exfiltration: Place access controls and monitor access to data to prevent lateral movements and protect your organisation’s intellectual property.
• Eliminate idle accounts: Purge your directory of orphan and dormant accounts immediately and continuously monitor for unused accounts and privileges. Ensure that non-active users, such as former employees, can no longer access the system or the organisation’s data.
• Investigate anomalous behaviour: Investigate any unusual activity in your organisation’s LAN to identify misbehaving employees. Combined with behaviour monitoring and analysis tools, you can efficiently identify and prevent insider threats.
• Conduct sentiment analysis: Perform sentiment analysis to determine the feelings and intentions of individuals. Regular analysis can help you identify employees under stress, experiencing financial troubles, or performing poorly, which may indicate potential malicious insiders.
• Implement insider threat detection tools: Use tools like Security Information and Event Management (SIEM) solutions, Endpoint Detection and Response (EDR), log management tools, User Behaviour Analytics (UEBA), IT Management (ITM), and security automation to detect and prevent insider threats.
• Leverage security automation: Implement security automation to understand baseline network behaviour and to react efficiently to different situations.
• Utilise employee awareness training: Use security awareness training to teach employees how to spot likely insider threat actors and make them aware of behavioural risk indicators.
• Conduct regular audits and reviews: Conduct regular audits and reviews of your security policies, procedures, and technologies to ensure they are up-to-date and effective in preventing insider threats.

By implementing these solutions, organisations can improve their security posture to stop insider threats and protect their critical information and systems.

As an industry-leading cybersecurity company, Proofpoint takes a people-centric approach to insider threat management and data loss prevention, enabling organisations to gain visibility, efficiency, and rapid response capabilities for mitigating the growing risks from insiders. Proofpoint offers several solutions to combat these insider threats:

Proofpoint Insider Threat Management (ITM) provides real-time, contextualised insights into user activity and behaviour to detect and prevent insider threats. Key capabilities include:

• Visibility and prevention: ITM provides visibility into the “who, what, when, and where” of user actions, with timeline views and screen captures to aid investigations. It can also block users from exfiltrating data across channels like USB, web uploads, cloud sync, and print.
• Efficiency: ITM offers a centralised view to help security teams correlate alerts and manage investigations across endpoints, the web, cloud, and email. It includes workflows for better collaboration and exportable reports for HR, legal, and other stakeholders.
• Rapid time to value: ITM is a scalable, cloud-native solution that can be deployed quickly with a lightweight endpoint agent, providing flexible monitoring of both everyday and high-risk users.

Proofpoint Enterprise Data Loss Prevention (DLP) integrates with ITM to provide comprehensive protection against data loss from negligent, compromised, and malicious users. It can identify sensitive data, detect exfiltration attempts, and automate regulatory compliance.

Proofpoint Security Awareness Training helps transform employees into effective data defenders by proactively identifying potentially risky users and changing their behaviour to ensure compliance.

To learn more about how to mitigate insider threats, contact Proofpoint.

[1] Verizon. “Data Breach Investigations Report”
[2] SANS. “Insider Threats and the Need for Fast and Directed Response”
[3] CSO Magazine. “U.S. State of Cybercrime Report”