What is NIST SP 800-30?
NIST Special Publication 800-30 is a guideline from the US National Institute of Standards and Technology (NIST) that describes a methodology for performing information security risk assessments.
The publication is part of the broader NIST Risk Management Framework and is applicable to both IT and OT environments, including industrial networks.
🧠 What does NIST SP 800-30 cover?
NIST SP 800-30 provides a step-by-step approach to identifying, analysing and evaluating information security risks. The aim is to enable well-considered decisions about whether or not to implement security measures.
Main steps in the process:
- Preparing for the risk analysis
- Defining scope, systems, environment and objectives
- Identifying risks
- Determining threats, vulnerabilities, vulnerable assets and existing controls
- Assessing risks
- Analysing the likelihood and impact of threats
- Estimating the risk (e.g. high, medium, low)
- Risk evaluation
- Comparing the risks against predefined risk tolerances
- Setting priorities
- Risk treatment
- Recommending mitigating measures, acceptance or transfer
- Monitoring and reviewing
- Evaluation and continuous improvement based on the PDCA cycle
📊 Risk model in NIST SP 800-30
The model uses the formula:
Risk = Likelihood × Impact
with additional factors such as:
- Threat sources (e.g. human error, malware, sabotage)
- Vulnerabilities (e.g. outdated software, open ports)
- Security measures (e.g. Firewall, Access Control, patch management)
🏭 Example in an OT context
| Asset | Threat | Vulnerability | Risk |
|---|---|---|---|
| PLC | External attacker via remote access | No MFA, old firmware | High |
| SCADA server | Ransomware via USB | No Application Control | Medium to high |
| Historian | DDoS attack | Unsecured API | Medium |
| HMI | Unauthorised modification | No RBAC | High |
🔐 Linkage with other frameworks
| Standard / framework | Relationship to SP 800-30 |
|---|---|
| NIST CSF | Risk analysis falls under the “Identify” function |
| ISO 27005 | Comparable approach with broader ISMS integration |
| IEC 62443-3-2 | Focuses on zones, SLs and OT-specific risks |
| FISMA | NIST 800-30 is mandatory for US government agencies |
✅ Benefits of NIST SP 800-30
- Flexible and applicable in both IT and OT
- Supports prioritisation of risks based on threat and impact
- Fully compatible with the NIST Risk Management Framework
- Suitable for use in critical infrastructure environments
📌 In summary
NIST SP 800-30 provides a structured methodology for the risk assessment of information systems. The approach is suitable for traditional IT environments as well as industrial networks (OT), and forms a basis for risk-driven security measures.