IT SECURITY

Internal threats

30. 4. 2026

When the Greatest Risk Sits Right in Your Office

While most defense systems focus on the external perimeter, the most devastating and direct risk resides inside your network – and carries a company access card. An Insider Threat is a threat that holds a legitimate authentication token and effectively bypasses all your firewalls.

The impact of these attacks is typically dramatically higher. An insider attacker knows the network topology, the location of critical data, and knows exactly where to strike.

When the Risk Carries a Company Access Card

Insider threats are not homogeneous. For strategic defense, you must identify the type of aggression – is it malicious intent, or simply human error 404?

1. Malicious Insider

An employee, contractor, or former partner who misuses access with the intent to cause harm, seek revenge, or exfiltrate IP for profit.

Negligent Insider (Human Error)

The most common initiation vector for external breaches. This involves unintentional failure: clicking on a malicious link, sending sensitive data to the wrong recipient, or neglecting security policies.

Compromised Insider (Compromised Account)

External attackers gain valid access through phishing or malware. The account appears legitimate but behaves maliciously. Detection is extremely difficult because the activities blend into standard usage patterns.

Statistics That Cannot Be Ignored

60% of all security incidents involve insider actors.

25% of data breaches are caused by ordinary human error.

34% of employees admit to bypassing security policies to “make their work easier”.

80% of the cost of an insider incident is detection and investigation, not the attack itself.

How Insider Threats Arise

Broad and Uncontrolled Access The phrase “give him admin rights so he can do everything” is a direct path to disaster.

Lack of Transparency and Logging Without active log monitoring and User and Entity Behavior Analytics (UEBA), it is nearly impossible to distinguish routine activity from malicious behavior.

Offboarding Gap and IP Exfiltration The period between resignation and system access termination is a critical window for intellectual property theft.

Poor Management of Vendors and Contractors Vendors and contractors often do not adhere to the same strict security policies as internal employees.

Defense Strategies Against Insider Threats

🔐 Principle of Least Privilege

Everyone should have only the access they actually need. Nothing more.

📊 Active Monitoring and Audit Logs

Monitoring anomalies, access to sensitive data, and configuration changes is a fundamental line of defense.

🧠 Training That Changes Behavior — Not Just a “Ticked-Off Course”

An employee who understands why security matters makes fewer mistakes.

🔄 Segmentation and Zero Trust

Trust nothing. Verify everything. Every access request should confirm it is authorized and secure.

📝 Strict Rules for External Access

Vendors must adhere to the same rules as employees, not fewer.

Do Not Wait for Devastation: How to Transform Trust into Managed Risk

Insider threats are inevitable and often hide within normal operations, masked under the guise of valid access rights. A successful defense can no longer rely on naive trust, but on intelligent risk management and continuous behavioral monitoring.

While external defense focuses on protecting the perimeter, a Zero Tolerance philosophy requires that zero tolerance for failure within the perimeter extend to zero tolerance for unaudited and continuously unverified access inside the network. This strategic shift is the only way to detect a threat before massive data exfiltration or total sabotage occurs.

Mitel: A Partner That Strengthens Security from Within

Mitel helps organizations protect the most sensitive points – access, identity, processes, and the daily work of employees. Insider threats cannot be “stopped by an antivirus.” They require a systematic approach: monitoring, identity management, and a security culture that minimizes the space for failure. Contact us and transform internal trust into managed, secure risk.

Author of the article:

Mitel