In the context of cybersecurity, most attention is typically focused on external attacks. Yet some of the most damaging incidents often originate from within the organization. All it takes is one compromised account, a disloyal employee, or misassigned access rights to cause a serious data breach, system disruption, or information theft.
Insider threat is not a theoretical concept – it’s a daily reality for financial institutions, IT companies, and organizations of all sizes. And what’s worse, it often goes undetected until it’s too late.
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What Is an Insider Threat?
A network security audit is not about quickly scanning the infrastructure or simply “ticking off” a compliance requirement. It is an in-depth analysis of the technical and organizational state of the network environment, aimed at identifying weaknesses before cybercriminals do. It allows you to assess how secure your network truly is – not in theory, but in practice, based on real-world threat scenarios.
A well-conducted audit reveals vulnerabilities, misconfigurations, unnecessarily open services, excessive privileges, or lack of segmentation. It also provides answers to questions that are often not asked on a daily basis: is it possible for someone to gain access to systems from the outside? Are sensitive data sufficiently protected? In case of an incident, does the organization know how to respond?
This is a process that brings real value – not only for the IT department, but also for management, auditors, compliance teams, and business owners. It provides a starting point for changes that genuinely increase the organization’s resilience.
Why Are Insider Threats So Dangerous?
An insider threat is one of the most difficult security risks to detect – and one of the most costly. Why? Because the insider already has access. There’s no need to bypass perimeter defenses, evade firewalls, or search for vulnerabilities – often, all it takes is using their own account.
Trust can become the greatest weakness. An administrator with broad privileges, an analyst with access to customer data, an IT staff member testing new solutions – each of these roles can unintentionally (or deliberately) expose the organization to serious damage.
What’s more, insider activity is harder to detect with SIEM, DLP, or EDR tools, as the actions usually fall within the boundaries of “normal” behavior. This isn’t a brute-force external attack – it’s a quiet abuse of legitimate access.
And most importantly – insider threats are not exceptions; they are the norm. In every organization, there’s the possibility that someone with access becomes a critical point of failure for security.
Insider Threat in Practice – How an Internal Incident Happens
Insider threats don't always begin with malicious intent. Often, it only takes a lack of awareness, haste, or insufficient oversight for an internal user to become the starting point of a security incident.
Unintentional Insider Threat – The Case of a Remote Employee
An accounting department employee works remotely using a personal laptop, connecting through an unsecured home Wi-Fi network with no password or basic protections. Although they have access to the company’s financial systems, they don’t use the recommended VPN connection because "it’s slower and sometimes drops." The IT department does not enforce the requirement to use a secure connection.
A few days earlier, the employee opened an email containing what appeared to be a legitimate invoice. The attachment looked normal, the document opened, and the computer seemed to function as usual. However, in the background, malware was silently installed and began exfiltrating data from company applications to external servers.
The result? Financial records, customer lists, and passwords stored in the browser began leaking from the corporate environment. The incident was detected only several days later through network traffic analysis. The impact? A data breach, costly forensic analysis, mandatory notification to the regulator and clients, and operational downtime for the finance team.
This insider threat case had nothing to do with malicious intent. It was a simple lack of awareness, combined with a failure to enforce security policies, that led to a serious incident.
Insider Threat Due to Negligence – The Forgotten Service Account
At a mid-sized financial institution, cooperation with an external IT contractor had come to an end. Although technical access to servers and applications should have been revoked immediately, one integration account used for testing remained active. It wasn’t visible in the main IAM system, as it had been created manually, bypassing the standard access provisioning procedure.
This account had access to the testing environment and partial access to production resources, including the CRM system and code repositories. For several weeks, no one noticed that the account was being accessed from unusual IP addresses outside working hours.
The result? A third party – possibly a former contractor employee or someone else entirely – used the account to deploy a malicious script that captured user login data and exfiltrated it outside the organization. The incident was detected only after analyzing anomalies in security logs. By that time, there had been data theft, unauthorized access to application code, and compromise of system integrity.
This is a textbook case of an insider threat caused by negligence – a lack of full control over user accounts and failure to account for "non-standard" scenarios in access management procedures.
Deliberate Insider Threat – Theft of Customer Data
In a customer service department of a large financial company, an employee had access to full personal data, transaction history, and KYC documents. He had been with the company for several years, was familiar with the systems, and knew that data access logs were recorded – but not actively reviewed.
Over time, frustration built up – a missed promotion, a conflict with a supervisor, and an increasing sense of anonymity in remote work. The employee began exporting customer data in small batches, uploading it to an encrypted cloud drive. He collected names, national ID numbers, addresses, and investment information. It was later discovered that the data had been sold illegally to an external marketing company.
The result? Loss of customer trust, a data breach notification to the supervisory authority, regulatory proceedings, and the need to implement costly remediation measures. The employee was terminated for cause and became the subject of a criminal investigation – but the data had already spread.
This is a clear case of a deliberate insider threat – a conscious act by someone who knows the system’s weaknesses and exploits the lack of monitoring and unenforced policies.
What Can You Do to Reduce Insider Threats?
Insider threats cannot be completely eliminated, but the risk can be significantly reduced. The key lies in combining technology, organizational policies, and employee education.
Insider threats cannot be completely eliminated, but they can be effectively managed – provided the organization takes a comprehensive approach. Protection against internal threats does not rely solely on technical tools. The key is the synergy of three elements: technology, organizational policies, and employee education.
What Should You Implement to Reduce the Risk?
🔹 Least Privilege Principle – Every employee should have access only to the resources necessary for their role.
🔹 Periodic Access Reviews – Regularly verify user permissions and remove accounts that are no longer needed.
🔹 User Activity Monitoring – Tools like SIEM, DLP, and UEBA help detect anomalies and potential abuse.
🔹 Organizational Awareness – Respond to risk indicators beyond the technical level (e.g., conflicts, behavior changes).
🔹 Education and Training – Raise employee awareness about their responsibility for protecting information.
🔹 Incident Documentation and Analysis – Every incident can provide valuable lessons – if properly understood.
Insider threats begin where control ends. Don’t wait until it’s too late.
What Can You Do Today to Reduce Insider Threat?
You don’t need to deploy complex enterprise-grade systems to start mitigating insider threats. Starting today, you can review who has access to customer data, servers, and production systems. Check whether inactive accounts – for example, from former employees or external vendors – are still present in your environment.
Assigning a single person responsible for access management and permission control is a simple yet effective step that brings structure to your processes. Even a brief security reminder to staff can significantly increase awareness and vigilance.
It’s also worth enabling basic log and access monitoring – the mere awareness that activities are being tracked can have a powerful deterrent and preventive effect. Insider threats don’t emerge overnight – but their consequences can be immediate. Whether you respond in time is up to you.
