Biblio
The cyber threat landscape is a constantly morphing surface; the need for cyber defenders to develop and create proactive threat intelligence is on the rise, especially on critical infrastructure environments. It is commonly voiced that Supervisory Control and Data Acquisition (SCADA) systems and Industrial Control Systems (ICS) are vulnerable to the same classes of threats as other networked computer systems. However, cyber defense in operational ICS is difficult, often introducing unacceptable risks of disruption to critical physical processes. This is exacerbated by the notion that hardware used in ICS is often expensive, making full-scale mock-up systems for testing and/or cyber defense impractical. New paradigms in cyber security have focused heavily on using deception to not only protect assets, but also gather insight into adversary motives and tools. Much of the work that we see in today's literature is focused on creating deception environments for traditional IT enterprise networks; however, leveraging our prior work in the domain, we explore the opportunities, challenges and feasibility of doing deception in ICS networks.
Critical Infrastructures (CIs) use Supervisory Control And Data Acquisition (SCADA) systems for remote control and monitoring. Sophisticated security measures are needed to address malicious intrusions, which are steadily increasing in number and variety due to the massive spread of connectivity and standardisation of open SCADA protocols. Traditional Intrusion Detection Systems (IDSs) cannot detect attacks that are not already present in their databases. Therefore, in this paper, we assess Machine Learning (ML) for intrusion detection in SCADA systems using a real data set collected from a gas pipeline system and provided by the Mississippi State University (MSU). The contribution of this paper is two-fold: 1) The evaluation of four techniques for missing data estimation and two techniques for data normalization, 2) The performances of Support Vector Machine (SVM), and Random Forest (RF) are assessed in terms of accuracy, precision, recall and F1score for intrusion detection. Two cases are differentiated: binary and categorical classifications. Our experiments reveal that RF detect intrusions effectively, with an F1score of respectively \textbackslashtextgreater 99%.
Security is one of the most important properties of electric power system (EPS). We consider the state estimation (SE) tool as a barrier to the corruption of data on current operating conditions of the EPS. An algorithm for a two-level SE on the basis of SCADA and WAMS measurements is effective in terms of detection of malicious attacks on energy system. The article suggests a methodology to identify cyberattacks on SCADA and WAMS.
Advent of Cyber has converted the entire World into a Global village. But, due to vurneabilites in SCADA architecture [1] national assests are more prone to cyber attacks.. Cyber invasions have a catastrophic effect in the minds of the civilian population, in terms of states security system. A robust cyber security is need of the hour to protect the critical information infastructrue & critical infrastructure of a country. Here, in this paper we scrutinize cyber terrorism, vurneabilites in SCADA network systems [1], [2] and concept of cyber resilience to combat cyber attacks.
Most of the countries evaluate their energy networks in terms of national security and define as critical infrastructure. Monitoring and controlling of these systems are generally provided by Industrial Control Systems (ICSs) and/or Supervisory Control and Data Acquisition (SCADA) systems. Therefore, this study focuses on the cyber-attack vectors on SCADA systems to research the threats and risks targeting them. For this purpose, TCP/IP based protocols used in SCADA systems have been determined and analyzed at first. Then, the most common cyber-attacks are handled systematically considering hardware-side threats, software-side ones and the threats for communication infrastructures. Finally, some suggestions are given.
Reliable operation of power systems is a primary challenge for the system operators. With the advancement in technology and grid automation, power systems are becoming more vulnerable to cyber-attacks. The main goal of adversaries is to take advantage of these vulnerabilities and destabilize the system. This paper describes a game-theoretic approach to attacker / defender modeling in power systems. In our models, the attacker can strategically identify the subset of substations that maximize damage when compromised. However, the defender can identify the critical subset of substations to protect in order to minimize the damage when an attacker launches a cyber-attack. The algorithms for these models are applied to the standard IEEE-14, 39, and 57 bus examples to identify the critical set of substations given an attacker and a defender budget.
Traffic of Industrial Control System (ICS) between the Human Machine Interface (HMI) and the Programmable Logic Controller (PLC) is known to be highly periodic. However, it is sometimes multiplexed, due to asynchronous scheduling. Modeling the network traffic patterns of multiplexed ICS streams using Deterministic Finite Automata (DFA) for anomaly detection typically produces a very large DFA and a high false-alarm rate. In this article, we introduce a new modeling approach that addresses this gap. Our Statechart DFA modeling includes multiple DFAs, one per cyclic pattern, together with a DFA-selector that de-multiplexes the incoming traffic into sub-channels and sends them to their respective DFAs. We demonstrate how to automatically construct the statechart from a captured traffic stream. Our unsupervised learning algorithms first build a Discrete-Time Markov Chain (DTMC) from the stream. Next, we split the symbols into sets, one per multiplexed cycle, based on symbol frequencies and node degrees in the DTMC graph. Then, we create a sub-graph for each cycle and extract Euler cycles for each sub-graph. The final statechart is comprised of one DFA per Euler cycle. The algorithms allow for non-unique symbols, which appear in more than one cycle, and also for symbols that appear more than once in a cycle. We evaluated our solution on traces from a production ICS using the Siemens S7-0x72 protocol. We also stress-tested our algorithms on a collection of synthetically-generated traces that simulated multiplexed ICS traces with varying levels of symbol uniqueness and time overlap. The algorithms were able to split the symbols into sets with 99.6% accuracy. The resulting statechart modeled the traces with a median false-alarm rate of as low as 0.483%. In all but the most extreme scenarios, the Statechart model drastically reduced both the false-alarm rate and the learned model size in comparison with the naive single-DFA model.
With the integration of computing, communication, and physical processes, the modern power grid is becoming a large and complex cyber physical power system (CPPS). This trend is intended to modernize and improve the efficiency of the power grid, yet it makes the CPPS vulnerable to potential cascading failures caused by cyber-attacks, e.g., the attacks that are originated by the cyber network of CPPS. To prevent these risks, it is essential to analyze how cyber-attacks can be conducted against the CPPS and how they can affect the power systems. In light of that General Packet Radio Service (GPRS) has been widely used in CPPS, this paper provides a case study by examining possible cyber-attacks against the cyber-physical power systems with GPRS-based SCADA system. We analyze the vulnerabilities of GPRS-based SCADA systems and focus on DoS attacks and message spoofing attacks. Furthermore, we show the consequence of these attacks against power systems by a simulation using the IEEE 9-node system, and the results show the validity of cascading failures propagated through the systems under our proposed attacks.
Online Dynamic Security Assessment (DSA) is a dynamical system widely used for assessing and analyzing an electrical power system. The outcomes of DSA are used in many aspects of the operation of power system, from monitoring the system to determining remedial action schemes (e.g. the amount of generators to be shed at the event of a fault). Measurement from supervisory control and data acquisition (SCADA) and state estimation (SE) results are the inputs for online-DSA, however, the SE error, caused by sudden change in power flow or low convergence rate, could be unnoticed and skew the outcome. Therefore, generator shedding scheme cannot achieve optimum but must have some margin because we don't know how SE error caused by these problems will impact power system stability control. As a method for solving the problem, we developed SE error detection system (EDS), which is enabled by detecting the SE error that will impact power system transient stability. The method is comparing a threshold value and an index calculated by the difference between SE results and PMU observation data, using the distance from the fault point and the power flow value. Using the index, the reliability of the SE results can be verified. As a result, online-DSA can use the SE results while avoiding the bad SE results, assuring the outcome of the DSA assessment and analysis, such as the amount of generator shedding in order to prevent the power system's instability.
In Industrial Control Systems (ICS/SCADA), machine to machine data traffic is highly periodic. Past work showed that in many cases, it is possible to model the traffic between each individual Programmable Logic Controller (PLC) and the SCADA server by a cyclic Deterministic Finite Automaton (DFA), and to use the model to detect anomalies in the traffic. However, a recent analysis of network traffic in a water facility in the U.S, showed that cyclic-DFA models have limitations. In our research, we examine the same data corpus; our study shows that the communication on all of the channels in the network is done in bursts of packets, and that the bursts have semantic meaning---the order within a burst depends on the messages. Using these observations, we suggest a new burst-DFA model that fits the data much better than previous work. Our model treats the traffic on each channel as a series of bursts, and matches each burst to the DFA, taking the burst's beginning and end into account. Our burst-DFA model successfully explains between 95% and 99% of the packets in the data-corpus, and goes a long way toward the construction of a practical anomaly detection system.
The modern world is becoming increasingly dependent on computing and communication technology to function, but unfortunately its application and impact on areas such as critical infrastructure and industrial control system (ICS) networks remains to be thoroughly studied. Significant research has been conducted to address the myriad security concerns in these areas, but they are virtually all based on artificial testbeds or simulations designed on assumptions about their behavior either from knowledge of traditional IT networking or from basic principles of ICS operation. In this work, we provide the most detailed characterization of an example ICS to date in order to determine if these common assumptions hold true. A live power distribution substation is observed over the course of two and a half years to measure its behavior and evolution over time. Then, a horizontal study is conducted that compared this behavior with three other substations from the same company. Although most predictions were found to be correct, some unexpected behavior was observed that highlights the fundamental differences between ICS and IT networks including round trip times dominated by processing speed as opposed to network delay, several well known TCP features being largely irrelevant, and surprisingly large jitter from devices running real-time operating systems. The impact of these observations is discussed in terms of generality to other embedded networks, network security applications, and the suitability of the TCP protocol for this environment.
During its nascent stages, Programmable Logic Controllers (PLC) were made robust to sustain tough industrial environments, but little care was taken to raise defenses against potential cyberthreats. The recent interconnectivity of legacy PLCs and SCADA systems with corporate networks and the internet has significantly increased the threats to critical infrastructure. To counter these threats, researchers have put their efforts in finding defense mechanisms that can protect the SCADA network and the PLCs. Encryption is a critical component of security and therefore has been used by many organizations to protect data on the network. However, since PLC vendors don't make available information about their hardware or software, it becomes challenging to embed encryption into their devices, especially if they rely on legacy protocols. This paper describes an alternative design using an open source PLC that was modified to encrypt all data it sends over the network, independently of the protocol used. Experimental results indicated that the encryption layer increased the security of the link without causing a significant overhead.
The exploitation of Industrial Control Systems (ICSs) has been described as both easy and impossible, where is the truth? PostStuxnet works have included a plethora of ICS focused cyber security research activities, with topics covering device maturity, network protocols, and overall cyber security culture. We often hear the notion of ICSs being highly vulnerable due to a lack of inbuilt security mechanisms, considered a low hanging fruit to a variety of low skilled threat actors. While there is substantial evidence to support such a notion, when considering targeted attacks on ICS, it is hard to believe an attacker with limited resources, such as a script kiddie or hacktivist, using publicly accessible tools and exploits alone, would have adequate knowledge and resources to achieve targeted operational process manipulation, while simultaneously evade detection. Through use of a testbed environment, this paper provides two practical examples based on a Man-In-The-Middle scenario, demonstrating the types of information an attacker would need obtain, collate, and comprehend, in order to begin targeted process manipulation and detection avoidance. This allows for a clearer view of associated challenges, and illustrate why targeted ICS exploitation might not be possible for every malicious actor.
Guidelines, directives, and policy statements are usually presented in ``linear'' text form - word after word, page after page. However necessary, this practice impedes full understanding, obscures feedback dynamics, hides mutual dependencies and cascading effects and the like, - even when augmented with tables and diagrams. The net result is often a checklist response as an end in itself. All this creates barriers to intended realization of guidelines and undermines potential effectiveness. We present a solution strategy using text as ``data'', transforming text into a structured model, and generate a network views of the text(s), that we then can use for vulnerability mapping, risk assessments and control point analysis. We apply this approach using two NIST reports on cybersecurity of smart grid, more than 600 pages of text. Here we provide a synopsis of approach, methods, and tools. (Elsewhere we consider (a) system-wide level, (b) aviation e-landscape, (c) electric vehicles, and (d) SCADA for smart grid).
This paper focuses on exploitable cyber vulnerabilities in industrial control systems (ICS) and on a new approach of resiliency against them. Even with numerous metrics and methods for intrusion detection and mitigation strategy, a complete detection and deterrence of cyber-attacks for ICS is impossible. Countering the impact and consequence of possible malfunctions caused by such attacks in the safety-critical ICS's, this paper proposes new controller architecture to fail-operate even under compromised situations. The proposed new ICS is realized with diversification of hardware/software and unidirectional communication in alerting suspicious infiltration to upper-level management. Equipped with control bus monitoring, this operation-basis approach of infiltration detection would become a truly cyber-resilient ICS. The proposed system is tested in a lab hardware experimentation setup and on a cybersecurity test bed, DeterLab, for validation.
This paper will suggest a robust method for a network layer Moving Target Defense (MTD) using symmetric packet scheduling rules. The MTD is implemented and tested on a Supervisory Control and Data Acquisition (SCADA) network testbed. This method is shown to be efficient while providing security benefits to the issues faced by the static nature of SCADA networks. The proposed method is an automated tool that may provide defense in depth when be used in conjunction with other MTDs and traditional security devices.
Smart grid is an evolving new power system framework with ICT driven power equipment massively layered structure. The new generation sensors, smart meters and electronic devices are integral components of smart grid. However, the upcoming deployment of smart devices at different layers followed by their integration with communication networks may introduce cyber threats. The interdependencies of various subsystems functioning in the smart grid, if affected by cyber-attack, may be vulnerable and greatly reduce efficiency and reliability due to any one of the device not responding in real time frame. The cyber security vulnerabilities become even more evident due to the existing superannuated cyber infrastructure. This paper presents a critical review on expected cyber security threats in complex environment and addresses the grave concern of a secure cyber infrastructure and related developments. An extensive review on the cyber security objectives and requirements along with the risk evaluation process has been undertaken. The paper analyses confidentiality and privacy issues of entire components of smart power system. A critical evaluation on upcoming challenges with innovative research concerns is highlighted to achieve a roadmap of an immune smart grid infrastructure. This will further facilitate R&d; associated developments.
Intrusion detection has been an active field of research for more than 35 years. Numerous systems had been built based on the two fundamental detection principles, knowledge-based and behavior-based detection. Anyway, having a look at day-to-day news about data breaches and successful attacks, detection effectiveness is still limited. Even more, heavy-weight intrusion detection systems cannot be installed in every endangered environment. For example, Industrial Control Systems are typically utilized for decades, charging off huge investments of companies. Thus, some of these systems have been in operation for years, but were designed afore without security in mind. Even worse, as systems often have connections to other networks and even the Internet nowadays, an adequate protection is mandatory, but integrating intrusion detection can be extremely difficult - or even impossible to date. We propose a new lightweight current-based IDS which is using a difficult to manipulate measurement base and verifiable ground truth. Focus of our system is providing intrusion detection for ICS and SCADA on a low-priced base, easy to integrate. Dr. WATTson, a prototype implemented based on our concept provides high detection and low false alarm rates.