Distinguishing and Understanding Insider Threats

Introduction

Insider threats are among one of the most prominent and detrimental challenges that cybersecurity and digital forensic professionals face today. Cybersecurity and Infrastructure Security Agency (CISA) defines an insider threat as the potential for an insider (individual who has authorized access or knowledge of an organization’s resources) to abuse their access to harm said organization [2]. Unlike external threat actors, insiders are more difficult to detect, since they involve individuals who have legitimate authorized access to critical systems and data. Consequently, insider activities often go unnoticed until the damage has already been done. Digital forensics plays a crucial role in identifying, analyzing, and mitigating insider threats. This post explores an examination of insider threats, techniques for detection and mitigation, as well as the anomalies to be on the lookout for.

Understanding Insider Threats

From 2019 to 2024, the number of organizations that report experiencing an insider attack has risen from 66% to 76% [7]. Additionally, the surge in popularity of remote work poses many challenges to cybersecurity and forensic experts. Accelerated by the covid-19 pandemic, there has been a significant global shift into remote working conditions [5]. As a result, insider threats present a greater challenge in today’s landscape. Remote work presents new opportunities for insider threats due to lack of physical oversight, unsecured home networks, and access control issues [5]. There is definitely a parallel between growing insider incidents and the cost for organizations. According to the 2023 Cost of Insider Risks Global Report by Ponemon Institute, the cost for insider attacks in North America has risen by 95%, jumping from $11 million to $19 million [6]. The impact of an insider attack can reach exceptionally large amounts because an insider incident can lead to damaging attacks like data breaches, ransom, fraud, and espionage.

Insider threats can be classified as intentional, negligent, or accidental, with each having their own motives [2]. Rationales like financial gain, revenge, sabotage, and personal gain all play a role for intentional/malicious insider attacks [8]. These types of insider threats look to benefit themselves by carrying out an attack within the organization, likely slipping through various security measures as they have proper access. The most common insider attack is unintentional or negligent insider threats. Their catalyst often consists of insufficient training, which leads to employees failing to protect their information and data [6, 8]. Finally, accidental or compromised insiders are classified as individuals who have already been compromised by an outside threat, despite their best efforts [6]. Regardless of the insider type, insiders pose a risk to information security assurance. Their complexities and varied motives highlight the importance of tailored security measures.

Detection & Mitigation

The reason why insider threats are so alarming is because attackers have legitimate credentials that traverse through an organization, easily going unnoticed. One of the tactics to identify insider threats is user and entity behavior analytics (UEBA), a security software that embodies advanced analytics by detecting unusual behavior and anomalies within user activity [1]. By applying machine learning, artificial intelligence, and automation, UEBA can analyze data from a number of sources (logs, network traffic, endpoint services, etc.) to create an idea of normal user behaviors [3]. Following this, UEBA conducts real time monitoring and flags cybersecurity teams once it detects anomalies that suggest an insider threat. For an advanced approach, a pairing of UEBA with other security systems such as endpoint detection and response (EDR), intrusion detection systems (IDS), and security information and event management (SIEM) ensures a multi-layered approach that enhances an organization’s ability to detect, analyze, and respond to threats effectively [3].

Zero Trust is another tactic that can enhance both detection and diminution of insider risk. IBM defines zero trust as a security strategy that enforces policies for each individual connection between users, devices, applications, and data [4]. In its simplest form, zero trust operates on the principle of ‘never trust, always verify.’ Some of the techniques under zero trust include user authentication processes, continuous authentication & authorization, constant auditing & logging, and establishing role-based access control policies [1]. Appropriately, applying zero trust ensures constant verification, limiting access, and maintaining high visibility into user actions. Thus, enabling a quick response to insider threats and limits the damage.

As negligence insiders are the most common insider type, the best preventative measure is to provide proper awareness training. Building security awareness prevents insider incidents by educating employees on security policies, proper data handling, and the risks of negligent behavior. Workers may be uneducated on common cyber threats and may not recognize suspicious activity. When the threat is a behavioral issue that is not digital, having employees in an in-person setting is one of the ways to detect an insider [1]. By recognizing insider threat indicators and understanding their consequences, employees are less likely to engage carelessly in malicious actions and more likely to promptly report. Implementation of proper security training and education fosters a security conscious culture that reduces all insider threats, especially unintentional.

Anomalies to Consider

Monitoring plays a critical part in distinguishing an insider threat. The biggest factor to detect an insider is to take note of any unusual behaviors or anomalies that have the potential to signal malicious or risky insider activities. Below are some key indicators to consider [1]:

1. Employee’s Physical Behavior: Employee is displaying a shift in their attitude at work. It could be a decline in work performance, resignation behavior, and/or increase in complaints.
2. Unusual Account Activity: User is looking to access files outside of their department, being active outside of normal work hours, frequent access attempts, sudden permission changes, etc.
3. Questionable File Activity: User account is uncharacteristically deleting, modifying, downloading, and transferring files.
4. Suspicious Communication: User is connecting with contacts outside of the organization via email, chat, etc.
5. Unordinary Network Activity: There are random or unexplained spikes in network traffic.

Conclusion

Insider threats continue to be one of the most adverse threats within an organization. Therefore, it is of utmost importance for forensic experts and cybersecurity professionals to identify and remediate insider threats as soon as possible. Having a deep understanding of insider threats as well as detection and mitigation techniques to combat them, gives an organization the ability to detect potential insiders, preventing an incident. By knowing what behaviors and anomalies to monitor, forensic investigators will be able to decipher an insider threat and perform a proper investigation.

References

[1] Chin, K. (2024, October 31). How To Detect and Prevent Insider Threats. UpGuard. https://www.upguard.com/blog/how-to-detect-and-prevent-insider-threats

[2] Defining insider threats: CISA. Cybersecurity and Infrastructure Security Agency CISA. (n.d.). https://www.cisa.gov/topics/physical-security/insider-threat-mitigation/defining-insider-threats

[3] Detecting insider threats: Leverage user behavior analytics. Security Intelligence. (2024, November 4). https://securityintelligence.com/posts/detecting-insider-threats-leverage-user-behavior-analytic

Lindemulder, G., & Kosinski, M. (2024, June 20). What is zero trust?. IBM. https://www.ibm.com/topics/zero-trust

[5] Oliver, T. (2024, August 16). Insider Threats in the Age of Remote Work: Unique Challenges and Solutions for Remote Environments. Kaseware. https://www.kaseware.com/post/insider-threats-in-the-age-of-remote-work-unique-challenges-and-solutions-for-remote-environments

[6] Olusanya, D. (2024, April 20). Insider Threat Detection: Identifying Anomalies and Abnormal Behavior. LinkedIn. https://www.linkedin.com/pulse/insider-threat-detection-identifying-anomalies-dami-olusanya-gn56c

[7] Schulze, H. (2024, August 28). New Report Reveals Insider Threat Trends, Challenges, and Solutions. Cybersecurity Insiders. https://www.cybersecurity-insiders.com/2024-insider-threat-report-trends-challenges-and-solutions/

[8] Tripwire Guest Authors. (2023, March 28). Motivations for Insider Threats: What to Watch Out For. Tripwire. https://www.tripwire.com/state-of-security/motivations-insider-threats-what-watch-out