⚖️ Risk analysis - IT Risk Management System (ITRMS)
Seven topics on risk analysis - how risks arise, how to model threats (DFD + STRIDE), how to assess and process risks according to international practice (ISO 31000, ISO/IEC 27005, NIST SP 800-30 and RMF, FAIR). Figures will apply to fiction, designed for training.
Basic concept of risk
Risk anatomy - from danger to risk
Application
Helps to formulate risk as a scenario, not just a "weak spot." Risk exists only when there is a source of threat, vulnerability AND a valuable asset.
Reference
ISO Guide 73:2009 (dictionary), ISO/IEC 27005:2022, NIST SP 800-30 Rev.1.
Safety Note
The residual risk is assessed, not the initial risk: decisions are made on what remains after controls. The risk appetite determines how much remaining risk is acceptable.
Risk Management Life Cycle
ITMS process - ISO/IEC 27005:2022 & ISO 31000:2018
Application
One repeatable process is valid for both ISO 27001 ISMS and NIS2. Identical steps, only changes volume and criteria.
Reference
ISO/IEC 27005:2022, ISO 31000:2018, NIST SP 800-39, NIST SP 800-37 Rev. 2 (RMF).
Safety Note
Risk analysis is not a one-off document. It shall be reviewed periodically and after each major change (new system, incident, new threat), otherwise it becomes misleading as it becomes obsolete.
Step-by-step threat identification
DFD, confidence limits and STRIDE
Data flow diagram (DFD): Rectangle = external entity, circle = process, open rectangle = data storage, arrow = data flows; dashed line = confidence limit where data crosses zones and focuses threats.
Application
Threatening modeling systematically answers four questions (Threat Modeling Manifesto): which we create, that can go wrong, what we do and whether we did well enough. DFD shows where the data is stored and through which channels travel; STRIDE by elements helps not forget any threat class.
Reference
Microsoft STRIDE, Thread Modeling Manifesto 2020, OWASP Thread Modeling, NIST SP 800-154, PASTA, LINDDUN, ISO/IEC 27005:2022, MITRE ATT&CK.
Safety Note
Models early and repeatedly - at every architectural change. Start with the most valuable assets ("crown jets") and the limits of reliability where data cross zones - there is the greatest risk. Each entry of the identified threat into the risk register shall be assessed (possibility × impact) and link to control (4 T).
Qualitative assessment
Risk matrix - Probability × effect (5×5)
Scale (3×3, 5×5) and thresholds must be aligned to the organisation's risk appetite - matrix is a communication tool, not an accurate measurement.
Application
Rapidly classify many risks according to severity and show where to start. Simple, understandable also for management and non-technical parties.
Reference
ISO/IEC 27005:2022, NIST SP 800-30 Rev.1 (appendix G/H/I), ISO/IEC 31010 (technical).
Safety Note
The matrix is subjective: the same "high' risks may not be comparable. For big decisions (investments, cyber insurance), add quantitative analysis.
Quantitative assessment
Risk of money - ALE, ROSI and FAIR
Application
ALE shows the expected annual loss in cash - it justifies budget controls and compares whether control costs less than the risk it eliminates (ROSI).
Reference
NIST SP 800-30 Rev. 1 (SLE/ARO/ALE), FAIR / The Open Group O-RT, O-RA, ISO/IEC 27005:2022.
Safety Note
Quantitative numbers look exactly, but it's only as good as the data behind them. Rare events with a huge impact (right risk) are not assessed by ALE - add to the scenarios.
Risk Treatment Options
Four options (4 T) and residual risk acceptance
Application
For each risk over appetite, one or more of the 4 T options shall be selected and recorded in the risk record with the responsible and the deadline.
Reference
ISO/IEC 27005:2022 (processing options), ISO/IEC 27001:2022 6.1.3 + Annex A (SoA), NIST SP 800-37 Rev. 2 (Authorize).
Safety Note
"Train" does not mean getting rid of: insurance covers part of the loss, but reputation and responsibility remain. Acceptance valid only knowingly and documented.
Standard and Compliance Card
Risk management standards and linking of NIS2/ISO/binding regulatory acts
Application
Helps to choose a method for certification (ISO 27005), authorisation system (NIST RMF) or money decisions (FAIR) starting from scratch.
Reference
ISO 31000, ISO/IEC 27005, ISO/IEC 31010, NIST SP 800-30/37/39, NIST CSF 2.0, FAIR, NIS2, Binding Regulations, GDPR.
Safety Note
Article 21 (2a) of the NIS2 requires a direct risk analysis. In Latvia, binding national and international laws and regulations and EU Implementing Regulation 2024/2690 - linking the risk register to them.
Abbreviations
All abbreviations used in the guide (original and meaning).
- ITRMS
- IT Risk Management System - IT risk management system.
- ISO/IEC
- International Organization for Standardization / International Electrotechnical Commission - International Standards Organizations.
- NIST SP
- NIST Special Publication - publication series of the U.S. National Standards Institute.
- RMF
- Risk Management Framework - NIST Risk Management Framework (SP 800-37).
- CSF
- Cybersecurity Framework - NIST cybersecurity framework (2.0).
- ISMS
- Information Security Management System - Information Security Management System (ISO/IEC 27001).
- SoA
- Statement of Application - Application declaration (ISO/IEC 27001 6.1.3).
- PDCA
- Plan-Do-Check-Act - plans to carry out the testing (continuous cycle of improvement).
- AV
- Asset Value - asset value.
- EF
- Exposure Factor - impact factor (the lost part of the asset).
- SLE
- Single Loss Expectancy - Loss of one event (AV × EF).
- ARO
- Annualized Rate of Occurrence - the annual frequency of the event.
- ALE
- Annualized Loss Expectancy - Annual Loss (SLE × ARO).
- ROSI
- Return on Security Investment - Return on security investments.
- FAIR
- Factor Analysis of Information Risk - quantitative risk model.
- LEF
- Loss Event Frequency (FAIR).
- LM
- Loss Magnitude - amount of loss (FAIR).
- O-RT / O-RA
- Open Group Risk Toxonomy / Risk Analysis - FAIR Standards.
- 4 T
- Treat, Transfer, Tolerate, Terminate - minimize, transfer, accept, avoid.
- NIS2
- Network and Information Security Directive 2.
- DORA
- Digital Operational Resilience Act - EU Digital Resilience Regulation (financial sector).
- TIBER-EU
- Three Intelligence-based Ethical Red Teaming - threat intelligence based tests.
- GDPR
- General Data Protection Regulation - General Data Protection Regulation.
- DPIA
- Data Protection Impact Assessment (GDPR 35).
- saistošie normatīvie akti
- Cabinet Regulations No. 397 (Implementation of CIS2 in Latvia).
- COSO ERM
- Committee of Sponsoring Organizations · Enterprise Risk Management.
- COBIT
- Control Objectives for Information and Related Technologies (ISACA).
- OCTAVE
- Operationally Critical Threat, Asset and Vulnerability Evaluation (CERT/SEI).
- FMEA
- File Mode and Effects Analysis - analysis of types and consequences of errors.
- IKT
- information and Communication Technologies (ICT).
- STRIDE
- Spooofing, Tampereing, Repudiation, Information breakdown, Denial of service, Elevation of privilege - Microsoft threat classification.
- DFD
- Data Flow Diagram - data flow diagram (entetties, processes, storages, flows, reliability limits).
- PASTA
- Process for Attack Simulation and Three Analysis - 7 stage risk-oriented threat modelling methodology.
- LINDDUN
- framework for modelling privacy threats (linked to GDPR/DPIA).
- ATT&CK
- Adversarial Tactics, Techniques & Common Knowledge - MITRE attacker tactics and technique base.