Risk Management - INCOSE UK Chapter
Transcription
Risk Management - INCOSE UK Chapter
Managing Cyber Security Risks in Industrial Control Systems with Game Theory and Viable System Modelling Konstantinos Theodoros Spyridopoulos Maraslis Theo Tryfonas © 2014 INCOSE UK Ltd. George Oikonomou Shancang Li What is it about? • Importance Industrial Control Systems (ICSs) can be considered as Critical Infrastructure (CI) and play a major role in Industry as they are used to control fundamental industrial processes such as power production, power distribution, transportation etc. Due to their national significance their protection is of vital importance. • Scope The creation of a method that provides cost-efficient Risk Management for an ICS. • Novelty The method takes into account the proprietary and interconnected nature of an ICS while combines Viable System Modelling (VSM) and Game Theory (GT). Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 2 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation A zero-sum Game is constructed where an attacker tries to harm an ICS as much as possible while a defender tries to defend the ICS in the best possible way. Both are rational players who seek for the strategy that will lead them to the highest individual reward. Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 3 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed Although we can easily identify the assets, valuating them requires: • Capturing the relationships between the Asset of an ICS • Capturing the relationships between the components of different ICSs • Consideration of the effect of a component’s failure to the rest of the components (within the same and different ICSs) 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 4 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 5 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation 2 Info about System’s Current Status 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 8. Strategies Assessment and Outcome (GT) 3 4 Communicates 5's Decisions Proposes Approaches for System’s Evolution 5 Manages/Controls its Units Audits its Operations 3* 7. Risk Evaluation Strategies Proposed Transfers Results of Coordination Transfers Results of Audit Risk Analysis Manages its Operations and Coordinates its Activities 4 Makes and Delivers Decisions about Changes Need to be Made 4 Identifies Changes in the Environment 1 Data Exchange Environ ment Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 6 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Value of Asset = (Market price) x (Number of connections) x (Effect on other ICSs) x (Role of the Asset) where, Effect on other ICSs = (Role of the Asset) / (Number of devices with the same role) Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 7 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed Identification and Assessment of Threads and Vulnerabilities is now possible since all interconnections are known. We only need to know the probability that a thread/attack is successful 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 8 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) Attacker’s Strategies Espionage Yes or No Confidentiality Security Attribute Integrity Availability Inveteracy of <1Year >1Year Vulnerability Very difficult Difficulty of Difficult Detection Easy Very Difficult Difficulty of Recovery Difficult (Cost of Healing) Easy Defender’s Strategies R&D Yes or No Never Patch Frequency 1 Year >1 Year IDS Yes or No Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 9 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 10 VSM in Details Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Under the rules: • Attack against Confidentiality cannot be very difficult to recover • Zero day attack cannot be easy to detect • >1Years attacks can only be easy to detect Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 11 Game Theory Risk Management Asset Identification and Evaluation Attacker’s Reward = Gain + Cost of Defense + Cost of Healing – Cost of Attack 1. Asset Identification 2. Asset Valuation where, Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed Gain = Value of Asset × Security Attribute × Probability of Successful Attack Cost of Defense = R&D + Patch Frequency + IDS Cost of Healing = Difficulty of Recovery Cost of Attack = Espionage + Inveteracy of Vulnerability × Difficulty of Detection 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 12 Game Theory Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) Attacker’s Strategies Espionage Confidentiality Security Attribute Integrity Availability Inveteracy of <1Year Vulnerability >1Year Very difficult Difficulty of Difficult Detection Easy Very Difficult Difficulty of Recovery Difficult (Cost of Healing) Easy Defender’s Strategies R&D Never Patch Frequency 1 Year >1 Year IDS Value of Asset Under Attack 30,000 0.33 1 1 1,000 10 4 1 0.5 101,000 1,000 10 10,000 0 1,000 100 10 90,000 Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 13 Results Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis Two Nash Equilibria in the form: A: (Attack, Espionage, Core Attribute, Inveteracy of Vulnerability, Difficulty of Detection, Difficulty of Recovery) D: (R&D, Patch Frequency, IDS) 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) A: (Yes, No, Integrity, < 1 Year, Very Difficult, Very Difficult) D: (Yes, > 1 Year, No) A: (Yes, No, Availability, 1 Year, Very Difficult, Very Difficult) D: (Yes, > 1 Year, No) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 14 Results Risk Management Asset Identification and Evaluation 1. Asset Identification 2. Asset Valuation Risk Analysis 3. Thread Identification 4. Thread Assessment 5. Vulnerability and Strategy Identification 6. Vulnerability Assessment Both Nash Equilibria lead to a reward for the attacker equal to 182,000 which means 182,000 loss for the defender since it is a zerosum game. 7. Risk Evaluation Strategies Proposed 8. Strategies Assessment and Outcome (GT) Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 15 Summary A novel cyber security risk management approach in ICSs which combines VSM with GT and takes into account the proprietary and interconnected nature of an ICS. Managing Cyber Security Risks in I ndustrial Control Systems with Game Theory and Viable System Modelling 16 References [1] K. Stouffer, J. Falco, and K. Scarfone, "Guide to industrial control systems (ICS) security," NIST Special Publication, pp. 800-82, 2011. [2] G. Digioia, C. Foglietta, S. Panzieri, and A. Falleni, "Mixed holistic reductionistic approach for impact assessment of cyber attacks," in Intelligence and Security Informatics Conference (EISIC), 2012 European, 2012, pp. 123-130. [3] M. Esmalifalak, G. Shi, Z. Han, and L. Song, "Bad data injection attack and defense in electricity market using game theory study," 2013. [4] M. Tambe and B. An, "Game Theory for Security: A Real-World Challenge Problem for Multiagent Systems and Beyond," Association for the Advancement of Artificial Intelligence, 2011. 17 Questions? 18 19