An insider threat occurs when an employee misuses company data, such as copying client information or proprietary data to a personal device, causing financial loss and reputational damage.
Introduction
Insider threats in cybersecurity are often overlooked. This blog highlights the risks of employees exfiltrating data before leaving and how Microsoft 365’s cloud usage telemetry can help identify and mitigate these dangers.
Understanding Insider Threats
Insider threats come from within the organisation and include:
- Malicious insiders: Intentionally steal or misuse data.
- Negligent insiders: Carelessness leads to breaches.
- Compromised insiders: Credentials stolen by attackers.
Why Insider Threats Are Often Ignored
Despite their potential impact, insider threats are frequently overlooked for several reasons:
- Trust: Organisations often inherently trust their employees, sometimes to a fault, leading to a lack of rigorous monitoring.
- Focus on External Threats: Cybersecurity efforts and resources are predominantly directed toward defending against external attackers, leaving internal vulnerabilities unaddressed.
- Complexity of Detection: Identifying insider threats can be challenging due to the subtlety of the activities and the difficulty in distinguishing between legitimate and malicious actions.
The Exfiltration Threat During Employee Exit
During an employee’s exit, insider threat risks increase, particularly data exfiltration:
- Downloading sensitive files to personal devices.
- Emailing data to personal accounts.
- Accessing unusual files could raise red flags.
Case in Point: The Months Leading to Resignment
Before announcing their resignation, employees with malicious intentions may show signs of data theft:
- Accessing files unrelated to their duties.
- Printing a large number of sensitive documents.
- Transferring large amounts of data.
Leveraging Cloud Usage Telemetry
With the advent of advanced telemetry capabilities within the most common company IT environments, such as Microsoft 365, organisations now have the tools to detect and respond to insider threats more effectively. Telemetry refers to the automated collection and transmission of data from remote sources, providing insights into user activities and behaviours.
Detecting Anomalies with Telemetry
Telemetry data can help identify unusual patterns and potential insider threats through:
- Behavioural Analytics: Analysing user behaviour to detect deviations from the norm, such as accessing files outside of typical work hours or downloading unusually large amounts of data.
- File Activity Monitoring: Tracking changes to files, including renaming, moving, and printing activities.
- Access Patterns: Monitoring which files are accessed and by whom, flagging any unusual access that may indicate data exfiltration.
Implementing Proactive Security Measures
To mitigate the risk of insider threats, organisations should implement several proactive security measures:
- Regular Audits: Conducting regular audits of user activities and file access logs to identify any suspicious behaviour.
- Access Controls: Implementing strict access controls to ensure that employees only have access to the information necessary for their roles.
- Exit Procedures: Establishing comprehensive exit procedures that include revoking access to sensitive information even whilst the employee is serving a notice period, and conducting thorough reviews of recent activities.
Conclusion
Insider threats represent a significant and often underestimated risk to organisational cybersecurity. The period leading up to an employee’s resignation is particularly critical, as the potential for data exfiltration increases. However, with the capabilities offered by cloud usage telemetry, such as Microsoft Graph in Microsoft 365, organisations can better detect and respond to these threats. By implementing proactive security measures and fostering a culture of cybersecurity awareness, businesses can safeguard their sensitive information and mitigate the impact of insider threats.
