• Communications for Statistical Applications and Methods
• /
• 제30권1호
• /
• pp.75-94
• /
• 2023

The growing trend of cyber risk has put forward the importance of cyber risk management. Cyber risk is defined as an accidental or intentional risk related to information and technology assets. Although cyber risk is a subset of operational risk, it is reported to be handled differently from operational risk due to its different features of the loss distribution. In this study, we aim to detect the characteristics of cyber loss and find a suitable model by measuring value at risk (VaR). We use the loss distribution approach (LDA) and the time series model to describe cyber losses of financial and non-financial business sectors, provided in SAS^® OpRisk Global Data. Peaks over threshold (POT) method is also incorporated to improve the risk measurement. For the financial sector, the LDA and GARCH model with POT perform better than those without POT, respectively. The same result is obtained for the non-financial sector, although the differences are not significant. We also build a two-dimensional model reflecting the dependence structure between financial and non-financial sectors through a bivariate copula and check the model adequacy through VaR.

• 정보보호학회논문지
• /
• 제27권5호
• /
• pp.1233-1245
• /
• 2017

지능정보사회를 선도하는 핵심 기술이자 서비스인 사물인터넷의 초연결성으로 인해 사이버리스크가 급증하면서 사이버리스크의 전가(Risk transfer)를 통해 경영환경의 안정성을 높이는 새로운 위험관리 방안으로 사이버보험(Cyber insurance)이 주목받고 있다. 그러나, 사이버보험은 아직 국내에서는 비교적 생소한 개념이다. 이에 본 연구에서는 국내 상황에서 우선적으로 요구되는 보장사항을 도출하여 국내 수요에 적합한 사이버보험의 개념을 제안하고자 하였다. 연구 결과 사이버보험의 수요자들은 사업손실과 배상책임에 가장 많은 필요성을 보이고 있는 것으로 나타났다.

• 한국항해항만학회:학술대회논문집
• /
• 한국항해항만학회 2019년도 추계학술대회
• /
• pp.134-136
• /
• 2019

국제해사기구(IMO)는 2017년 해상 사이버 위험관리 지침(Guidelines on maritime cyber risk management)을 발표했다. IMO의 해상 사이버 위험관리 지침에 따라 각 기국은 2021년 1월 1일 이후 도래하는 첫 번째 연차심사 전까지 안전관리규약(ISM, International Safety Management Code)의 선박안전관리시스템(SMS, Safety Management System)에서 사이버 리스크에 관한 사항을 통합·관리 하여야 한다. 본 논문에서는 해상분야의 사이버 보안 관리대상 및 위험요소를 식별하고 취약성 분석을 수행하기 위하여 IMO가 제시한 산업계 지침 및 국제표준을 근거로 해상분야의 사이버 보안 취약분야를 관리적·기술적·물리적 보안의 세 가지 영역으로 구분하였다. 또한, 리스크 매트릭스(Risk Matrix)를 사용하여 보안영역별 위험요소에 따른 정성적 리스크 평가(RA, Risk Assessment)를 수행하였다.

• International Journal of Computer Science & Network Security
• /
• 제22권6호
• /
• pp.390-399
• /
• 2022

Cyber security and resilience are phrases that describe safeguards of ICTs (information and communication technologies) from cyber-attacks or mitigations of cyber event impacts. The sole purpose of Risk models are detections, analyses, and handling by considering all relevant perceptions of risks. The current research effort has resulted in the development of a new paradigm for safeguarding services offered online which can be utilized by both service providers and users. customers. However, rather of relying on detailed studies, this approach emphasizes task selection and execution that leads to successful risk treatment outcomes. Modelling intelligent CSGs (Cyber Security Games) using MLTs (machine learning techniques) was the focus of this research. By limiting mission risk, CSGs maximize ability of systems to operate unhindered in cyber environments. The suggested framework's main components are the Threat and Risk models. These models are tailored to meet the special characteristics of online services as well as the cyberspace environment. A risk management procedure is included in the framework. Risk scores are computed by combining probabilities of successful attacks with findings of impact models that predict cyber catastrophe consequences. To assess successful attacks, models emulating defense against threats can be used in topologies. CSGs consider widespread interconnectivity of cyber systems which forces defending all multi-step attack paths. In contrast, attackers just need one of the paths to succeed. CSGs are game-theoretic methods for identifying defense measures and reducing risks for systems and probe for maximum cyber risks using game formulations (MiniMax). To detect the impacts, the attacker player creates an attack tree for each state of the game using a modified Extreme Gradient Boosting Decision Tree (that sees numerous compromises ahead). Based on the findings, the proposed model has a high level of security for the web sources used in the experiment.

• Nuclear Engineering and Technology
• /
• 제53권10호
• /
• pp.3319-3326
• /
• 2021

As a form of industrial control systems (ICS), nuclear instrumentation and control (I&C) systems have been digitalized increasingly. This has raised in turn cyber security concerns. Cyber security for ICS is important because cyber-attacks against ICS can cause not only equipment damage and loss of production but also personal and public safety hazards unlike in general IT environments. Numerous risk analyses have been carried out to enhance the safety of ICS and recently, many studies related to the cyber security of ICS are being conducted. Many existing risk analyses and cyber security studies have considered safety and cyber security separately. However, both safety and cyber security perspectives should be considered when analyzing risks for complex and critical ICS facilities such as nuclear power plants (NPPs). In this paper, the STPA-SafeSec methodology is selected to consider both safety and security perspectives when performing a risk analysis for NPPs in order to assess impacts on the safety by cyber-attacks against the digital I&C systems. The STPA-SafeSec methodology was applied to a test-bed system that simulates a condensate water (CD) system in an NPP. The process of the application up to the development of mitigation strategies is described in detail.

• 한국컴퓨터정보학회논문지
• /
• 제24권11호
• /
• pp.99-107
• /
• 2019

사이버 보안을 위한 활동인 '위험관리(Risk management)'와 '보안관제(security monitoring)' 업무는 미래에 발생할 보안 위협에 대비하고 보안 사고를 최소화 하는 활동이라는 점에서 깊은 상관관계를 가지고 있다. 또한 위험관리와 보안관제 분야 모두 관리자에게 시각적으로 그 정보자산에 대한 위협을 보여주는 패턴 모델을 적용하는 것이 효과적이다. 검증받은 패턴모델로는 전통적인 품질관리 분야에서 오랫동안 사용되어온 '관리도'(control chart)모델이 존재하지만 정보시스템의 사이버 위험관리와 보안관제에서의 활용은 부족하다. 이에 본 논문에서는 위험관리와 보안관제 시스템을 통합한 사이버 SRM(Security Risk Monitoring)시스템을 설계하였다. SRM은 '관리도'의 패턴을 이용한 '보안대책' (security control)의 적용 전략을 제시한다. 보안대책은 기존의 표준화된 보안대책 집합인 ISMS, NIST SP 800-53, CC를 통합적으로 적용하였다. 이를 활용하여 2014~2018년 까지 4년간 우리나라사이버위기 경보동향을 분석하였고 이는 향후 보다 유연한 보안대책 수립을 가능하게 한다.

• Nuclear Engineering and Technology
• /
• 제44권8호
• /
• pp.919-928
• /
• 2012

The applications of computers and communication system and network technologies in nuclear power plants have expanded recently. This application of digital technologies to the instrumentation and control systems of nuclear power plants brings with it the cyber security concerns similar to other critical infrastructures. Cyber security risk assessments for digital instrumentation and control systems have become more crucial in the development of new systems and in the operation of existing systems. Although the instrumentation and control systems of nuclear power plants are similar to industrial control systems, the former have specifications that differ from the latter in terms of architecture and function, in order to satisfy nuclear safety requirements, which need different methods for the application of cyber security risk assessment. In this paper, the characteristics of nuclear power plant instrumentation and control systems are described, and the considerations needed when conducting cyber security risk assessments in accordance with the lifecycle process of instrumentation and control systems are discussed. For cyber security risk assessments of instrumentation and control systems, the activities and considerations necessary for assessments during the system design phase or component design and equipment supply phase are presented in the following 6 steps: 1) System Identification and Cyber Security Modeling, 2) Asset and Impact Analysis, 3) Threat Analysis, 4) Vulnerability Analysis, 5) Security Control Design, and 6) Penetration test. The results from an application of the method to a digital reactor protection system are described.

• International journal of advanced smart convergence
• /
• 제11권3호
• /
• pp.7-16
• /
• 2022

The targets of cyber-attacks are not limited to the websites and internal IT systems of shipping agencies. Ships and ports have become important targets for cyber attackers. This paper examines the current state of ship network security, introduces the International Maritime Organization's resolution on ship network security management, and summarizing the cyber-attacks in maritime so the readers can have a general understanding of maritime environment.

• International Journal of Computer Science & Network Security
• /
• 제23권5호
• /
• pp.179-192
• /
• 2023

The widespread use of Cloud Computing, Internet of Things (IoT), and social media in the Information Communication Technology (ICT) field has resulted in continuous and unavoidable cyber-attacks on users and critical infrastructures worldwide. Traditional security measures such as firewalls and encryption systems are not effective in countering these sophisticated cyber-attacks. Therefore, Intrusion Detection and Prevention Systems (IDPS) are necessary to reduce the risk to an absolute minimum. Although IDPSs can detect various types of cyber-attacks with high accuracy, their performance is limited by a high false alarm rate. This study proposes a new technique called Fuzzy Logic - Objective Risk Analysis (FLORA) that can significantly reduce false positive alarm rates and maintain a high level of security against serious cyber-attacks. The FLORA model has a high fuzzy accuracy rate of 90.11% and can predict vulnerabilities with a high level of certainty. It also has a mechanism for monitoring and recording digital forensic evidence which can be used in legal prosecution proceedings in different jurisdictions.

• Nuclear Engineering and Technology
• /
• 제49권3호
• /
• pp.517-524
• /
• 2017

Cyber security is an important issue in the field of nuclear engineering because nuclear facilities use digital equipment and digital systems that can lead to serious hazards in the event of an accident. Regulatory agencies worldwide have announced guidelines for cyber security related to nuclear issues, including U.S. NRC Regulatory Guide 5.71. It is important to evaluate cyber security risk in accordance with these regulatory guides. In this study, we propose a cyber security risk evaluation model for nuclear instrumentation and control systems using a Bayesian network and event trees. As it is difficult to perform penetration tests on the systems, the evaluation model can inform research on cyber threats to cyber security systems for nuclear facilities through the use of prior and posterior information and backpropagation calculations. Furthermore, we suggest a methodology for the application of analytical results from the Bayesian network model to an event tree model, which is a probabilistic safety assessment method. The proposed method will provide insight into safety and cyber security risks.