What Is an Insider Threat?

• Insider Threat Definition

  Insider Threat Definition

  An insider attack poses a significant security risk to a business as it originates from within the organizational network and is often difficult to detect due to the involvement of trusted personnel. Such risks can emerge from the negligent behavior of employees towards IT security; hence, continuous monitoring of all user activity is crucial.
• Types of insider threats

  Types of insider threats

  Outlined below are common types of insider threats:

  Malicious insiders: are also known as turncloaks as they steal a company's intellectual property, such as trade secrets and patents, unobtrusively. It can be an employee or third-party contractor who misuses access rights to exfiltrate valuable information for personal or financial profits. Disgruntled employees who want to sabotage an organization's reputation and make quick progress in their career through illicit ways fall under this category, typically. Turncloaks are generally well aware of an organization's internal security procedures.

  Negligent insiders: are sometimes termed “goofs” by security specialists as they often ignore the recommended IT security policies despite knowing them, such as setting weak system passwords and opening suspicious emails. This provides an opportunity for attackers to infiltrate an organization's network by exploiting the vulnerabilities created by such users. Goofs are the primary victim of social engineering attacks.

  Collusive insiders: are people who work in coordination with the external threat actors, such as APT groups, to cause damage to an organization. Their primary motive is to stealthily transfer an organization's confidential data to outside allies for financial incentives. Spotting such malicious insiders is often arduous as they use sophisticated security strategies or technologies to avoid detection.

  Compromised insiders: typically include employees who use malicious systems. Their credentials are often exposed in a data breach or security incident, allowing attackers to steal classified company data while acting as legitimate users. Threat actors can use this information to escalate their privileges and jeopardize other sensitive systems in the organization.
• Insider threat indicators

  Insider threat indicators

  Insider attack indicators can be classified into two categories mainly: digital and behavioral.

  Digital Indicators

  Excessive data download: when an employee regularly downloads data without any valid reason. Such users attempt to transfer large volumes of data outside the organizational network during off-hours.

  Abnormal access requests: malicious insiders often look for opportunities to access sensitive data or applications non-related to their job function in the pre-attack stage, indicating the possibility of a future internal attack.

  Unauthorized storage media use: employees storing classified company data is another warning signal of an impending insider attack for security teams.

  Network scanning for security vulnerabilities: an employee doing this without permission can be a cue of an upcoming breach. These malicious actors also modify the existing security controls of an organization to create additional vulnerabilities, such as delaying updates and altering system configuration.

  Suspicious email communication: employees communicating with recipients outside the organizational network often signify an ongoing insider attack, particularly if the mail contains sensitive business documents or files.

  Behavioral Indicators

  Disgruntlement: employees who are dissatisfied with their jobs or looking to sabotage an organization's reputation may be involved in an insider attack. They often violate company policies, argue with co-workers, and underperform by missing deadlines and making frequent mistakes.

  Overenthusiasm: such as working late at night at the office without any demand and repeatedly volunteering for additional work. Employees exhibiting such unusual behavior can be internal threats.

  Unexplained financial gains: an employee who has previously expressed monetary woes who suddenly has unexplained financial gains can be a warning sign of a malicious insider, such as abrupt loan settlement and luxurious item purchases. Such a person could be involved in transferring a company's confidential data to its rivals as part of industrial espionage.

  Unusual overseas travel: an employee traveling to a country where none of their friends or relatives live and is also not a tourist destination without a valid reason can be an indicator of corporate or foreign espionage.
• How to detect an insider threat

  How to detect an insider threat

  Besides implementing cybersecurity training and awareness programs, security teams should employ modern threat detection and prevention tools, such as security information and event management (SIEM) and identity and access management (IAM) software, to track malicious insiders. An impactful insider attack prevention system unites multiple security tools to identify abnormal user behavior, reduce false positives, and prevent data loss.

  Outlined below are some of the key benefits and use cases of insider attack detection and prevention solutions.

  User account management

  Knowing Active Directory accounts and groups arrangement is crucial to track malicious insiders' potential attack vectors. With modern IAM tools, security teams can easily monitor and audit Group Policy and Active Directory, using customized reports and dashboard visualizations to track every change and associated personnel. They can also quickly identify and deactivate dormant user accounts to prevent access to critical servers and data by former employees using IAM solutions.

  Least privilege access

  The risk of privilege creep is typically high with malicious insiders as they switch roles or departments, making it challenging for security staff to track them. IT staff can prevent abuse of privileges by insiders with automated, role-based user provisioning using modern IAM tools. It ensures people with the same job profile or seniority get the same level of access for higher security and consistency during access delegation.

  Data staging and exfiltration identification

  Malicious insiders typically look for opportunities to move sensitive information into the staging zone for smooth extrusion. They also coordinate with external attackers to launch a DDoS attack to spike the network traffic to avoid detection. Security teams can detect such compromised user accounts involved in anomalous data staging and transfer using real-time log and event correlation, forensic analysis, and threat intelligence capabilities found in SIEM solutions.

  Unauthorized storage media detection

  Malicious internal actors typically use illegitimate storage devices, such as USB flash drives and hard disks, while stealing sensitive company data. With SIEM tools, security teams can receive real-time alerts to illicit USB device connections and subsequently block their usage. This also helps prevent insiders from running malicious code or applications directly through USB devices to compromise system security.

  File integrity monitoring (FIM)

  Continuous monitoring of file or configuration changes on servers, databases, network devices, and applications is crucial to mitigate the risk of insider attacks. With FIM-enabled SIEM tools, IT staff can quickly detect and discard suspicious activity across critical system files. Additionally, SIEM tools can correlate the file audit events and security logs to identify local file changes due to malware, APTs, and other advanced attacks.