What is a Cybersecurity Risk Assessment?
A Cybersecurity Risk Assessment is the systematic identification, analysis and evaluation of cyber threats, vulnerabilities and risks within IT and OT environments. In an industrial context it helps determine which digital risks could endanger the production process or safety, and which measures are required.
A risk assessment is indispensable for establishing an effective cybersecurity strategy, in line with standards such as IEC 62443, ISO 27001 or NIST CSF.
🧠 How does a Cybersecurity Risk Assessment work?
- Defining the scope
- Which systems, networks and processes fall within the assessment?
- Including PLC, SCADA, HMI, Historian, Remote Access, Engineering Station
- Identifying threats
- Internal and external threats: Insider Threat, Phishing, ransomware, human error
- Drawing on Threat Intelligence and MITRE ATT&CK for ICS
- Identifying vulnerabilities
- For example: no Firewall, legacy hardware, unpatched software, weak passwords
- Determining impact
- What happens if a vulnerability is exploited? Consider:
- Production stoppage
- Environmental risk
- Safety incident
- Reputational damage
- Estimating likelihood
- Probability of exploitation (based on existing security measures, threat level, exposure)
- Calculating the risk score
- Impact × Likelihood = Risk score
- Plotted on a risk matrix or heatmap
- Recommending measures
- Technical: anomaly detection, Zero Trust, Access Control, encryption
- Organisational: Security Awareness, Incident Response Plan, patch management
- Prioritising via approaches such as Defense in Depth or IEC 62443 Security Level
🏭 Use in an OT context
| OT-specific factors | Explanation |
|---|---|
| Legacy systems | Not designed with cybersecurity in mind |
| Real-time requirements | Not all security measures can be applied without impact |
| Physical safety & production | Cyber risks can have operational or life-threatening consequences |
| Protocol diversity | Modbus, OPC UA and S7 each require specific evaluation |
OT risk assessments require close collaboration between security, operations and engineering.
🔐 Risk Assessment frameworks
- IEC 62443-3-2: Risk assessment for industrial automation
- ISO 27005: Risk management for information security
- NIST SP 800-30: Guide for conducting risk assessments
- BIO: Dutch baseline for government bodies
- COBIT: Governance framework with risk models
📌 In summary
A Cybersecurity Risk Assessment is essential for evaluating the resilience of OT environments and managing risks proactively. It helps prioritise investments, improve processes and meet regulatory requirements.