Modeling and predicting the behavior of nodes and users in blockchains provide opportunities for business strategy optimization. Indeed, the number of interactions of a node is strictly related to its balance and its prediction may be used for analytics purposes and investment strategies. However, the amount and diversity of information stored on the blockchain demand advanced tools for the modeling and analysis of blockchain data. Such tools should be able to capture the dynamicity and interaction of multiple independent actors, considering a large number of variables and dynamic interaction graph topologies. This is exacerbated by the use of smart contracts, programs stored in blockchain blocks that bring automation to blockchain's operations and thus increasing the variability of the resulting interaction graphs. Existing modeling methodologies are unable to keep track of all these details, as they are not able to capture the temporal variability of the network. In this paper, we propose a novel framework for modeling and predicting the behavior of smart contracts on a blockchain. We propose the concept of temporal smart contracts networks, i.e., graphs representing the temporal evolution of interactions and data flow. Our framework allows the creation of temporal smart contract networks with different granularity levels by considering different interaction patterns between smart contracts, externally owned accounts, and internal transactions. Thanks to these graphs, we are able to model features such as the node in degree and amount of ether received by a smart contract, which are directly related to its behavior. We incorporate our modeling approach in Ethereum Data Inspection Tool (EDIT), a novel tool able to model interactions and predict them based on historical data. We test different machine learning models to predict features extracted by EDIT, hence allowing for the prediction of the overall behavior of the smart contract. We test EDIT on the Ethereum blockchain and model several temporal smart contracts networks, which represent the interactions and the data flow resulting from about 4 000 000 consecutive blocks. The evaluation of different real case studies shows that the proposed framework is able to predict, with a mean absolute error close to 1%, the evolution of several interesting properties (e.g., amount of received ether) related to both accounts and smart contracts.

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Video surveillance systems provide means to detect the presence of potentially malicious drones in the surroundings of critical infrastructures. In particular, these systems collect images and feed them to a deep-learning classifier able to detect the presence of a drone in the input image. However, current classifiers are not efficient in identifying drones that disguise themselves with the image background, e.g., hiding in front of a tree. Furthermore, video-based detection systems heavily rely on the image’s brightness, where darkness imposes significant challenges in detecting drones. Both these phenomena increase the possibilities for attackers to get close to critical infrastructures without being spotted and hence be able to gather sensitive information or cause physical damages, possibly leading to safety threats. In this article, we propose RANGO, a drone detection arithmetic able to detect drones in challenging images where the target is difficult to distinguish from the background. RANGO is based on a deep learning architecture that exploits a Preconditioning Operation (PREP) that highlights the target by the difference between the target gradient and the background gradient. The idea is to highlight features that will be useful for classification. After PREP, RANGO uses multiple convolution kernels to make the final decision on the presence of the drone. We test RANGO on a drone image dataset composed of multiple already-existing datasets to which we add samples of birds and planes. We then compare RANGO with multiple currently existing approaches to show its superiority. When tested on images with disguising drones, RANGO attains an increase of 6.6% mean Average Precision (mAP) compared to YOLOv5 solution. When tested on the conventional dataset, RANGO improves the mAP by approximately 2.2%, thus confirming its effectiveness also in the general scenario.

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Predicting and classifying faults in electricity networks is crucial for uninterrupted provision and keeping maintenance costs at a minimum. Thanks to the advancements in the field provided by the smart grid, several data-driven approaches have been proposed in the literature to tackle fault prediction tasks. Implementing these systems brought several improvements, such as optimal energy consumption and quick restoration. Thus, they have become an essential component of the smart grid. However, the robustness and security of these systems against adversarial attacks have not yet been extensively investigated. These attacks can impair the whole grid and cause additional damage to the infrastructure, deceiving fault detection systems and disrupting restoration. In this paper, we present FaultGuard, the first framework for fault type and zone classification resilient to adversarial attacks. To ensure the security of our system, we employ an Anomaly Detection System (ADS) leveraging a novel Generative Adversarial Network training layer to identify attacks. Furthermore, we propose a low-complexity fault prediction model and an online adversarial training technique to enhance robustness. We comprehensively evaluate the framework’s performance against various adversarial attacks using the IEEE13-AdvAttack dataset, which constitutes the state-of-the-art for resilient fault prediction benchmarking. Our model outclasses the state-of-the-art even without considering adversaries, with an accuracy of up to 0.958. Furthermore, our ADS shows attack detection capabilities with an accuracy of up to 1.000. Finally, we demonstrate how our novel training layers drastically increase performances across the whole framework, with a mean increase of 154% in ADS accuracy and 118% in model accuracy.

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Automatic Dependent Surveillance-Broadcast (ADS-B) is an integral part of the Next Generation Air Transport System, providing an efficient and safe transport infrastructure by monitoring and managing congested airspace through advanced surveillance. It is designed to replace traditional radar-based communication with a reliable system that requires aircraft to periodically transmit their real-time positions to the air traffic control center and nearby planes. However, despite being a relatively new standard, it lacks security measures. The absence of encryption and authentication leaves it vulnerable to various attacks, including spoofing (message injection or modification), deletion, jamming, and eavesdropping. While eavesdropping may not have immediate consequences, message spoofing can lead to severe traffic disruptions and potential aircraft collisions. Although authentication may mitigate the issue, it is incompatible with existing infrastructure and requires modifications to the current ADS-B protocol. In this paper, we propose Hexa-ML, a novel one-class classifier-based approach to detect location spoofing attacks without requiring ADS-B protocol modifications. We focus on an attacker sending ADS-B signals with a location report that does not match its current location, and we aim to identify such attempts. Our method leverages the idea that a specific location should be associated with a physical signal with specific characteristics. To this aim, we divide the space with a hexagonal tessellation and train a one-class classifier for each hexagon with physical layer features of messages received within the hexagon. These features include power, as well as statistical characteristics of magnitude and power spectrum. The idea is that, if during detection the message does not generate from within a hexagon, its associated one-class classifier should reject it. To validate our approach, we deployed a testbed to collect real ADS-B signals from real airplanes during their cruise. Our experimental results consistently demonstrate that the Isolation Forest (IF) algorithm, implemented in both libraries, performs better than One-class SVM (OCSVM) (macro average F1-score 89%) and achieves an average F1-score of 93% within geospatial hexagonal cells.

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Smart waste management systems (SWMSs) represent a fundamental technology to efficiently manage the waste management and disposal process. Indeed, they provide means to efficiently manage the collection process, optimize resources, and foster the adoption of recycling policies. These systems are increasingly more connected and equipped with communication and sensing capabilities. Currently, the research on SWMSs security only focuses on the communication part. However, SWMSs may be subject to different cyber-physical threats due to the interconnection of information and operational technologies. In this article, we investigate the security and privacy issues of SWMSs from a cyber-physical system perspective. To provide a clear understanding of the possible threats, we first provide an overview of the current state of the art on SWMSs implementations. We then review the attacks and security measures proposed in the literature, showing that they solely focus on communication technologies. Then, we provide a thorough overview of all possible cyber-physical threats toward SWMSs. Our analysis shows that SWMSs are still vulnerable to a large number of threats impacting both the system's and the users' security, privacy, and safety.

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Dynamic Wireless Power Transfer (DWPT) is a novel technology that allows charging an electric vehicle while driving thanks to a dedicated road infrastructure. DWPT's capabilities in automatically establishing charging sessions and billing without users' intervention make it prone to cybersecurity attacks. Hence, security is essential in preventing fraud, impersonation, and user tracking. To this aim, researchers proposed different solutions for authenticating users. However, recent advancements in quantum computing jeopardize classical public key cryptography, making currently existing solutions in DWPT authentication nonviable. To avoid the resource burden imposed by technology upgrades, it is essential to develop post-quantum-resistant solutions. In this paper, we propose DynamiQS, the first post-quantum secure authentication protocol for dynamic wireless charging. DynamiQS is privacy-preserving and secure against attacks on the DWPT. We leverage an Identity-Based Encryption with Lattices in the Ring Learning With Error framework. Furthermore, we show the possibility of using DynamiQS in a real environment, leveraging the results of cryptographic computation on real constrained devices and simulations. DynamiQS reaches a total time cost of around 281 ms, which is practicable in dynamic charging settings (car and charging infrastructure).@en

In this paper, we investigate the security implications of virtualized and software-based Open Radio Access Network (RAN) systems, specifically focusing on the architecture proposed by the O-RAN ALLIANCE and O-Cloud deployments based on the O-RAN Software Community (OSC) stack and infrastructure. Our key findings are based on a thorough security assessment and static scanning of the OSC Near Real-Time RAN Intelligent Controller (RIC) cluster. We highlight the presence of potential vulnerabilities and misconfigurations in the Kubernetes infrastructure supporting the RIC, also due to the usage of outdated versions of software packages, and provide an estimation of their criticality using various deployment auditing frameworks (e.g., MITRE ATT&CK and the NSA CISA). In addition, we propose methodologies to minimize these issues and harden the Open RAN virtualization infrastructure. These encompass the integration of security evaluation methods into the deployment process, implementing deployment hardening measures, and employing policy-based control for RAN components. We emphasize the need to address the problems found in order to improve the overall security of virtualized Open RAN systems.

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Modern cars' complexity and increased reliance on electronic components have made them a prime target for attackers. In particular, the in-vehicle communication system is one of the major attack surfaces, with the Controller Area Network (CAN) being the most used protocol. CAN connects electronic components with each other, allowing them to communicate and carry out control functions, as well as managing the vehicle state. However, these components, called Electronic Control Units (ECUs), can also be exploited for malicious purposes. Indeed, since the CAN bus was not designed with security features, attackers can exploit its vulnerabilities to compromise ECUs and corrupt the communication, allowing for remote vehicle control, disabling breaks, and engine shutdowns, causing significant safety threats. In response to the absence of standardized authentication protocols within the automotive domain, researchers propose diverse solutions, each with unique strengths and vulnerabilities. However, the continuous influx of new protocols and potential oversights in meeting security requirements and essential operational features further complicate the implementability of these protocols. This paper comprehensively reviews and compares the 15 most prominent authentication protocols for the CAN bus. Our analysis emphasizes their strengths and weaknesses, evaluating their alignment with critical security requirements for automotive authentication. Additionally, we evaluate protocols based on essential operational criteria that contribute to ease of implementation in predefined infrastructures, enhancing overall reliability and reducing the probability of successful attacks. Our study reveals a prevalent focus on defending against external attackers in existing protocols, exposing vulnerabilities to internal threats. Notably, authentication protocols employing hash chains, Mixed Message Authentication Codes, and asymmetric encryption techniques emerge as the most effective approaches. Through our comparative study, we classify the considered protocols based on their security attributes and suitability for implementation, providing valuable insights for future developments in the field.

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Firstly introduced in 2013, Ethereum revolutionized the concept of blockchain. Compared to the previous generation of blockchains with the main representative the Bitcoin, the Ethereum blockchain extends the applications of this technology to domains such as its transfer of information and inclusion of off-chain data inside the blockchain. Furthermore, with the introduction of smart contracts, Ethereum allows for the automatic execution of operations inside the blockchain. These represent the key steps Ethereum firstly posed to enhance the blockchain technology and lead it to its widespread application. In this chapter we present an overview of the fundamental aspects that characterize the Ethereum blockchain. We discuss both its implementation from a blockchain point of view and the fundamental algorithmic aspects that characterize its functioning. Furthermore, we discuss the known vulnerabilities and security issues related to all the presented building blocks of Ethereum. Our aim is to provide a clear state-of-the-art overview of both the implementation aspects and security of the Ethereum blockchain.

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Hyperloop is among the most prominent future transportation systems. It involves novel technologies to allow traveling at a maximum speed of 1220km/h while guaranteeing sustainability. Due to the system's performance requirements and the critical infrastructure it represents, its safety and security must be carefully considered. In transportation systems, cyberattacks could lead to safety issues with catastrophic consequences for the population and the surrounding environment. To this day, no research inves-tigated the cybersecurity issues of the Hyperloop technology. In this paper, we provide the first analysis of the cybersecurity challenges of the interconnections between the different components of the Hyperloop ecosystem. We base our analysis on the currently available Hyperloop implementations, distilling those features that will likely be present in its final design. Moreover, we investigate possible infrastructure management approaches and their security concerns. Finally, we discuss countermeasures and future directions for the security of the Hyperloop design.@en

The secure transmission of instructions among vehicles in a platoon is one of the most essential needs for a vehicle platoon. Despite the existence of cryptographic methods to securely share instructions, instruction sharing is still subject to forgery, tampering, and denial-of-service attacks. Therefore, it is urgent to find a solution to perform data source identification to filter out irrelevant information (not instructions) while ensuring the authenticity of encrypted instructions is urgent to address. In addition, immediate revocation of credentials is also a crucial requirement for a vehicle platoon when an authorized vehicle member misbehaves. In this paper, we propose the first Secure Source Identification Scheme for Revocable Instruction Sharing (SI-RIS) to securely simultaneously achieve bilateral fine-grained access control, data source identification, immediate vehicle user revocation, and efficient encryption in vehicle platoons. Specifically, our SI-RIS solution supports fine-grained access control for both the sender and receiver over the encrypted instructions. As a result, only authorized correspondents are able to access the commands. Furthermore, upon identification of malicious members in the platoon, our SI-RIS provides an efficient direct vehicle user revocation mechanism capable of immediate revocation credentials without affecting other vehicles. We prove the security of our SI-RIS via rigorous mathematical security proof. Moreover, performance evaluation and comparisons illustrate the feasibility and practicability of SI-RIS for vehicle platoon.

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Electric Vehicles (EVs) represent a green alternative to traditional fuel-powered vehicles. To enforce their widespread use, both the technical development and the security of users shall be guaranteed. Users' privacy represents a possible threat that impairs the adoption of EVs. In particular, recent works showed the feasibility of identifying EVs based on the current exchanged during the charging phase. In fact, while the resource negotiation phase runs over secure communication protocols, the signal exchanged during the actual charging contains features peculiar to each EV. In what is commonly known as profiling, a suitable feature extractor can associate such features to each EV.In this article, we propose EVScout2.0, an extended and improved version of our previously proposed framework to profile EVs based on their charging behavior. By exploiting the current and pilot signals exchanged during the charging phase, our scheme can extract features peculiar for each EV, hence allowing their profiling. We implemented and tested EVScout2.0 over a set of real-world measurements considering over 7,500 charging sessions from a total of 137 EVs. In particular, numerical results show the superiority of EVScout2.0 with respect to the previous version. EVScout2.0 can profile EVs, attaining a maximum of 0.88 for both recall and precision scores in the case of a balanced dataset. To the best of the authors' knowledge, these results set a new benchmark for upcoming privacy research for large datasets of EVs.

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Autonomous driving is a research direction that has gained enormous traction in the last few years thanks to advancements in Artificial Intelligence (AI). Depending on the level of independence from the human driver, several studies show that Autonomous Vehicles (AVs) can reduce the number of on-road crashes and decrease overall fuel emissions by improving efficiency. However, security research on this topic is mixed and presents some gaps. On one hand, these studies often neglect the intrinsic vulnerabilities of AI algorithms, which are known to compromise the security of these systems. On the other, the most prevalent attacks towards AI rely on unrealistic assumptions, such as access to the model parameters or the training dataset. As such, it is unclear if autonomous driving can still claim several advantages over human driving in real-world applications. This paper evaluates the inherent risks in autonomous driving by examining the current landscape of AV sand establishing a pragmatic threat model. Through our analysis, we develop specific claims highlighting the delicate balance between the advantages of AVs and potential security challenges in real-world scenarios. Our evaluation serves as a foundation for providing essential takeaway messages, guiding both researchers and practitioners at various stages of the automation pipeline. In doing so, we contribute valuable insights to advance the discourse on the security and viability of autonomous driving in real-world applications.@en

The Controller Area Network (CAN) protocol is the most widely used standard for in-vehicle networks. However, the CAN protocol lacks essential security features (e.g., encryption) which makes it vulnerable to exploits by an adversary. In this paper, we develop CANLP, a Natural Language Processing (NLP)-based intrusion detection system to find whether a transmitted message originated from a legitimate ECU or an adversary. CANLP uses the Term Frequency-Inverse Document Frequency (TF-IDF) to discern complex features associated with CAN data and trains ML models with these features to identify fuzzing, spoofing, and masquerade attacks. When an attack is detected, CANLP identifies the specific ECU on which the attack was mounted on. Through extensive experiments on four public vehicle network datasets, we show that CANLP performs attack classification with high F1-score of 0.9974. We also demonstrate using a testbed that CANLP can be deployed for attack detection on resource-constrained hardware a latency of < 0.05 ms.

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Critical infrastructures (CIs), such as military bases and airports, are putting a lot of attention into defending against attacks delivered via drones by deploying drone detection systems. However, the CI area might be very large, with no-fly zones extending to regions where it might not be possible to deploy a power line for resourceful cameras. To this aim, the CI might deploy an Internet of Things (IoT)-based surveillance camera system to capture drone images. However, these IoT cameras are resource-constrained devices that cannot support the currently available detectors. In this article, we propose Light-YOLOv5, a lightweight image-based drone detector for resource-constrained cameras. We make targeted improvements to YOLOv5, including the replacement of the backbone network, the introduction of the transformer module, and the design of a parallel mixed efficient attention module (PEAM). We show that our modifications allow for reduced network size while achieving better classification than other state-of-the-art solutions. To prove these claims, we expanded an already available data set of blurred drone images by adding clear images of aircraft and birds. Since airplanes and birds are easily confused as drones by image classifiers, our addition proves the effectiveness of our solution. Experiments show that Light-YOLOv5 can achieve a very good tradeoff between performance (74.8% mAP) and efficiency (170 FPS). Compared to YOLOv5, Light-YOLOv5 improves mAP by 4.1%, reduces the number of network parameters by 15.7%, can perform detection at 170 frames per second (FPS), and achieves an average accuracy rate of 93.8%.

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The smart grid represents a pivotal innovation in modernizing the electricity sector, offering an intelligent, digitalized energy network capable of optimizing energy delivery from source to consumer. It hence represents the backbone of the energy sector of a nation. Due to its central role, the availability of the smart grid is paramount and is hence necessary to have in-depth control of its operations and safety. To this aim, researchers developed multiple solutions to assess the smart grid’s stability and guarantee that it operates in a safe state. Artificial intelligence and Machine learning algorithms have proven to be effective measures to accurately predict the smart grid’s stability. Despite the presence of known adversarial attacks and potential solutions, currently, there exists no standardized measure to protect smart grids against this threat, leaving them open to new adversarial attacks. In this paper, we propose GAN-GRID a novel adversarial attack targeting the stability prediction system of a smart grid tailored to real-world constraints. Our findings reveal that an adversary armed solely with the stability model’s output, devoid of data or model knowledge, can craft data classified as stable with an Attack Success Rate (ASR) of 0.99. Also by manipulating authentic data and sensor values, the attacker can amplify grid issues, potentially undetected due to a compromised stability prediction system. These results underscore the imperative of fortifying smart grid security mechanisms against adversarial manipulation to uphold system stability and reliability.

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We consider the problem of publicly verifiable privacy-preserving data aggregation in the presence of a malicious aggregator colluding with malicious users. State-of-the-art solutions either split the aggregator into two parties under the assumption that they do not collude, or require many rounds of interactivity and have non-constant verification time. In this work, we propose mPVAS, the first publicly verifiable privacy-preserving data aggregation protocol that allows arbitrary collusion, without relying on trusted third parties during execution, where verification runs in constant time. We also show three extensions to mPVAS: mPVAS+, for improved communication complexity, mPVAS-IV, for the identification of malicious users, and mPVAS-UD, for graceful handling of reduced user availability without the need to redo the setup. We show that our schemes achieve the desired confidentiality, integrity, and authenticity. Finally, through both theoretical and experimental evaluations, we show that our schemes are feasible for real-world applications.

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Today, we rely on contactless smart cards to perform several critical operations (e.g., payments and accessing buildings). Attacking smart cards can have severe consequences, such as losing money or leaking sensitive information. Although the security protections embedded in smart cards have evolved over the years, those with weak security properties are still commonly used. Among the different solutions, blocking cards are affordable devices to protect smart cards. These devices are placed close to the smart cards, generating a noisy jamming signal or shielding them. Whereas vendors claim the reliability of their blocking cards, no previous study has ever focused on evaluating their effectiveness. In this paper, we shed light on the security threats on smart cards in the presence of blocking cards, showing the possibility of being bypassed by an attacker. We analyze blocking cards by inspecting their emitted signal and assessing a vulnerability in their internal design.We propose a novel attack that bypasses the jamming signal emitted by a blocking card and reads the content of the smart card. We evaluate the effectiveness of 11 blocking cards when protecting a MIFARE Ultralight smart card and a MIFARE Classic card. Of these 11 cards, we managed to bypass 8 of them and successfully dump the content of a smart card despite the presence of the blocking card. Our findings highlight that the noise type implemented by the blocking cards highly affects the protection level achieved by them. Based on this observation, we propose a countermeasure that may lead to the design of effective blocking cards. To further improve security, we released the tool we developed to inspect the spectrum emitted by blocking cards and set up our attack.

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