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  1. Cyber-physical systems tightly integrate computational resources with physical processes through sensing and actuating, widely penetrating various safety-critical domains, such as autonomous driving, medical monitoring, and industrial control. Unfortunately, they are susceptible to assorted attacks that can result in injuries or physical damage soon after the system is compromised. Consequently, we require mechanisms that swiftly recover their physical states, redirecting a compromised system to desired states to mitigate hazardous situations that can result from attacks. However, existing recovery studies have overlooked stochastic uncertainties that can be unbounded, making a recovery infeasible or invalidating safety and real-time guarantees. This paper presents a novel recovery approach that achieves the highest probability of steering the physical states of systems with stochastic uncertainties to a target set rapidly or within a given time. Further, we prove that our method is sound, complete, fast, and has low computational complexity if the target set can be expressed as a strip. Finally, we demonstrate the practicality of our solution through the implementation in multiple use cases encompassing both linear and nonlinear dynamics, including robotic vehicles, drones, and vehicles in high-fidelity simulators. 
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    Free, publicly-accessible full text available May 13, 2025
  2. Free, publicly-accessible full text available February 28, 2025
  3. Free, publicly-accessible full text available July 1, 2024
  4. Anomaly detection can ensure the operational integrity of control systems by identifying issues such as faulty sensors and false data injection attacks. At the same time, we need privacy to protect personal data and limit the information attackers can get about the operation of a system. However, anomaly detection and privacy can sometimes be at odds, as monitoring the system’s behavior is impeded by data hiding. Cryptographic tools such as garbled circuits and homomorphic encryption can help, but each of these is best suited for certain different types of computation. Control with anomaly detection requires both types of computations so a naive cryptographic implementation might be inefficient. To address these challenges, we propose and implement protocols for privacy-preserving anomaly detection in a linear control system using garbled circuits, homomorphic encryption, and a combination of the two. In doing so, we show how to distribute private computations between the system and the controller to reduce the amount of computation–in particular at the low-power system. Finally, we systematically compare our proposed protocols in terms of precision, computation, and communication costs. 
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  5. The widespread availability of vulnerable IoT devices has resulted in IoT botnets. A particularly concerning IoT botnet can be built around high-wattage IoT devices such as EV chargers because, in large numbers, they can abruptly change the electricity consumption in the power grid. These attacks are called Manipulation of Demand via IoT (MaDIoT) attacks. Previous research has shown that the existing power grid protection mechanisms prevent any large-scale negative consequences to the grid from MaDIoT attacks. In this paper, we analyze this assumption and show that an intelligent attacker with extra knowledge about the power grid and its state, can launch more sophisticated attacks. Rather than attacking all locations at random times, our adversary uses an instability metric that lets the attacker know the specific time and geographical location to activate the high-wattage bots. We call these new attacks MaDIoT 2.0. 
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  6. The widespread availability of vulnerable IoT devices has resulted in IoT botnets. A particularly concerning IoT botnet can be built around high-wattage IoT devices such as EV chargers because, in large numbers, they can abruptly change the electricity consumption in the power grid. These attacks are called Manipulation of Demand via IoT (MaDIoT) attacks. Previous research has shown that the existing power grid protection mechanisms prevent any large-scale negative consequences to the grid from MaDIoT attacks. In this paper, we analyze this assumption and show that an intelligent attacker with extra knowledge about the power grid and its state, can launch more sophisticated attacks. Rather than attacking all locations at random times, our adversary uses an instability metric that lets the attacker know the specific time and geographical location to activate the high-wattage bots. We call these new attacks MaDIoT 2.0. 
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  7. Natural gas distribution networks are part of a nation’s critical infrastructure, ensuring gas delivery to households and industries (e.g., power plants) with the correct chemical composition and the right conditions of pressure and temperature. Gas distribution is monitored and controlled by a Supervisory Control and Data Acquisition (SCADA) network, which provides centralized monitoring and control over the physical process.In this paper, we conduct the first openly available network measurement study of the SCADA network of an operational large-scale natural gas distribution network. With a total of 154 remote substations communicating through the SCADA system with a Control Room and over 98 days of observation, this is, to the best of our knowledge, the most extensive dataset of this kind analyzed to date.By combining the information obtained from engineering and IEC 104 network traffic, we reconstruct the gas distribution system’s layout, including the type and purpose of the substations and the physical properties of the gas that enters the SCADA system. Our analysis shows that it is possible to extract this information, essential for security monitoring, purely from the raw network traffic and without background knowledge provided by the control system engineers. We also note that configuration changes in SCADA environments, although probably less frequent than in IT environments, are not as rare and exceptional as the research community assumed. 
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  8. If a trader could predict price changes in the stock market better than other traders, she would make a fortune. Similarly in the electricity market, a trader that could predict changes in the electricity load, and thus electricity prices, would be able to make large profits. Predicting price changes in the electricity market better than other market participants is hard, but in this paper, we show that attackers can manipulate the electricity prices in small but predictable ways, giving them a competitive advantage in the market. Our attack is possible when the adversary controls a botnet of high wattage devices such as air conditioning units, which are able to abruptly change the total demand of the power grid. Such attacks are called Manipulation of Demand via IoT (MaDIoT) attacks. In this paper, we present a new variant of MaDIoT and name it Manipulation of Market via IoT (MaMIoT). MaMIoT is the first energy market manipulation cyberattack that leverages high wattage IoT botnets to slightly change the total demand of the power grid with the aim of affecting the electricity prices in the favor of specific market players. Using real-world data obtained from two major energy markets, we show that MaMIoT can significantly increase the profit of particular market players or financially damage a group of players depending on the motivation of the attacker. 
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