Biblio

Utility networks are part of every nation's critical infrastructure, and their protection is now seen as a high priority objective. In this paper, we propose a threat awareness architecture for critical infrastructures, which we believe will raise security awareness and increase resilience in utility networks. We first describe an investigation of trends and threats that may impose security risks in utility networks. This was performed on the basis of a viewpoint approach that is capable of identifying technical and non-technical issues (e.g., behaviour of humans). The result of our analysis indicated that utility networks are affected strongly by technological trends, but that humans comprise an important threat to them. This provided evidence and confirmed that the protection of utility networks is a multi-variable problem, and thus, requires the examination of information stemming from various viewpoints of a network. In order to accomplish our objective, we propose a systematic threat awareness architecture in the context of a resilience strategy, which ultimately aims at providing and maintaining an acceptable level of security and safety in critical infrastructures. As a proof of concept, we demonstrate partially via a case study the application of the proposed threat awareness architecture, where we examine the potential impact of attacks in the context of social engineering in a European utility company.

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.

The Internet of Things (IoT) devices perform security-critical operations and deal with sensitive information in the IoT-based systems. Therefore, the increased deployment of smart devices will make them targets for cyber attacks. Adversaries can perform malicious actions, leak private information, and track devices' and their owners' location by gaining unauthorized access to IoT devices and networks. However, conventional security protocols are not primarily designed for resource constrained devices and therefore cannot be applied directly to IoT systems. In this paper, we propose Boot-IoT - a privacy-preserving, lightweight, and scalable security scheme for limited resource devices. Boot-IoT prevents a malicious device from joining an IoT network. Boot-IoT enables a device to compute a unique identity for authentication each time the device enters a network. Moreover, during device to device communication, Boot-IoT provides a lightweight mutual authentication scheme that ensures privacy-preserving identity usages. We present a detailed analysis of the security strength of BootIoT. We implemented a prototype of Boot-IoT on IoT devices powered by Contiki OS and provided an extensive comparative analysis of Boot-IoT with contemporary authentication methods. Our results show that Boot-IoT is resource efficient and provides better scalability compared to current solutions.

The globalization of integrated circuit (IC) supply chain and the emergence of threats, such as intellectual property (IP) piracy, reverse engineering, and hardware Trojans, have forced semiconductor companies to revisit the trust in the supply chain. Logic locking is emerging as a popular and effective countermeasure against these threats. Over the years, multiple logic techniques have been developed. Moreover, a number of attacks have been proposed that expose the security vulnerabilities of these techniques. This paper highlights the key developments in the logic locking research and presents a comprehensive literature review of logic locking.

Scan-based test is commonly used to increase testability and fault coverage, however, it is also known to be a liability for chip security. Research has shown that intellectual property (IP) or secret keys can be leaked through scan-based attacks. In this paper, we propose a dynamically-obfuscated scan design for protecting IPs against scan-based attacks. By perturbing all test patterns/responses and protecting the obfuscation key, the proposed architecture is proven to be robust against existing non-invasive scan attacks, and can protect all scan data from attackers in foundry, assembly, and system developers (i.e., OEMs) without compromising the testability. Furthermore, the proposed architecture can be easily plugged into EDA generated scan chains without having a noticeable impact on conventional integrated circuit (IC) design, manufacturing, and test flow. Finally, detailed security and experimental analyses have been performed on several benchmarks. The results demonstrate that the proposed method can protect chips from existing brute force, differential, and other scan-based attacks that target the obfuscation key. The proposed design is of low overhead on area, power consumption, and pattern generation time, and there is no impact on test time.

Cyber-Physical Systems (CPS) represent a fundamental link between information technology (IT) systems and the devices that control industrial production and maintain critical infrastructure services that support our modern world. Increasingly, the interconnections among CPS and IT systems have created exploitable security vulnerabilities due to a number of factors, including a legacy of weak information security applications on CPS and the tendency of CPS operators to prioritize operational availability at the expense of integrity and confidentiality. As a result, CPS are subject to a number of threats from cyber attackers and cyber-physical attackers, including denial of service and even attacks against the integrity of the data in the system. The effects of these attacks extend beyond mere loss of data or the inability to access information system services. Attacks against CPS can cause physical damage in the real world. This paper reviews the challenges of providing information assurance services for CPS that operate critical infrastructure systems and industrial control systems. These methods are thorough measures to close integrity and confidentiality gaps in CPS and processes to highlight the security risks that remain. This paper also outlines approaches to reduce the overhead and complexity for security methods, as well as examine novel approaches, including covert communications channels, to increase CPS security.

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.

Industrial Control System (ICS) consists of large number of electronic devices connected to field devices to execute the physical processes. Communication network of ICS supports wide range of packet based applications. A growing issue with network security and its impact on ICS have highlighted some fundamental risks to critical infrastructure. To address network security issues for ICS a clear understanding of security specific defensive countermeasures is required. Reconnaissance of ICS network by deep packet inspection (DPI) consists analysis of the contents of the captured packets in order to get accurate measures of process that uses specific countermeasure to create an aggregated posture. In this paper we focus on novel approach by presenting a technique with captured network traffic. This technique is capable to identify the protocols and extract different features for classification of traffic based on network protocol, header information and payload to understand the whole architecture of complex system. Here we have segregated possible types of attacks on ICS.

The threats of reverse-engineering, IP piracy, and hardware Trojan insertion in the semiconductor supply chain are greater today than ever before. Split manufacturing has emerged as a viable approach to protect integrated circuits (ICs) fabricated in untrusted foundries, but has high cost and/or high performance overhead. Furthermore, split manufacturing cannot fully prevent untargeted hardware Trojan insertions. In this paper, we propose to insert additional functional circuitry called obfuscated built-in self-authentication (OBISA) in the chip layout with split manufacturing process, in order to prevent reverse-engineering and further prevent hardware Trojan insertion. Self-tests are performed to authenticate the trustworthiness of the OBISA circuitry. The OBISA circuit is connected to original design in order to increase the strength of obfuscation, thereby allowing a higher layer split and lower overall cost. Additional fan-outs are created in OBISA circuitry to improve obfuscation without losing testability. Our proposed gating mechanism and net selection method can ensure negligible overhead in terms of area, timing, and dynamic power. Experimental results demonstrate the effectiveness of the proposed technique in several benchmark circuits.

We present a brief survey on the state-of-the-art design and verification techniques: IC obfuscation, watermarking, fingerprinting, metering, concurrent checking and verification, for mitigating supply chain security risks such as IC misusing, counterfeiting and overbuilding.

Memristors are an attractive option for use in future memory architectures due to their non-volatility, high density and low power operation. Notwithstanding these advantages, memristors and memristor-based memories are prone to high defect densities due to the non-deterministic nature of nanoscale fabrication. The typical approach to fault detection and diagnosis in memories entails testing one memory cell at a time. This is time consuming and does not scale for the dense, memristor-based memories. In this paper, we integrate solutions for detecting and locating faults in memristors, and ensure post-silicon recovery from memristor failures. We propose a hybrid diagnosis scheme that exploits sneak-paths inherent in crossbar memories, and uses March testing to test and diagnose multiple memory cells simultaneously, thereby reducing test time. We also provide a repair mechanism that prevents faults in the memory from being activated. The proposed schemes enable and leverage sneak paths during fault detection and diagnosis modes, while still maintaining a sneak-path free crossbar during normal operation. The proposed hybrid scheme reduces fault detection and diagnosis time by ~44%, compared to traditional March tests, and repairs the faulty cell with minimal overhead.
 

Integrated circuits (ICs) are now designed and fabricated in a globalized multivendor environment making them vulnerable to malicious design changes, the insertion of hardware Trojans/malware, and intellectual property (IP) theft. Algorithmic reverse engineering of digital circuits can mitigate these concerns by enabling analysts to detect malicious hardware, verify the integrity of ICs, and detect IP violations. In this paper, we present a set of algorithms for the reverse engineering of digital circuits starting from an unstructured netlist and resulting in a high-level netlist with components such as register files, counters, adders, and subtractors. Our techniques require no manual intervention and experiments show that they determine the functionality of >45% and up to 93% of the gates in each of the test circuits that we examine. We also demonstrate that our algorithms are scalable to real designs by experimenting with a very large, highly-optimized system-on-chip (SOC) design with over 375000 combinational elements. Our inference algorithms cover 68% of the gates in this SOC. We also demonstrate that our algorithms are effective in aiding a human analyst to detect hardware Trojans in an unstructured netlist.
 

Security of a computer system has been traditionally related to the security of the software or the information being processed. The underlying hardware used for information processing has been considered trusted. The emergence of hardware Trojan attacks violates this root of trust. These attacks, in the form of malicious modifications of electronic hardware at different stages of its life cycle, pose major security concerns in the electronics industry. An adversary can mount such an attack with an objective to cause operational failure or to leak secret information from inside a chip-e.g., the key in a cryptographic chip, during field operation. Global economic trend that encourages increased reliance on untrusted entities in the hardware design and fabrication process is rapidly enhancing the vulnerability to such attacks. In this paper, we analyze the threat of hardware Trojan attacks; present attack models, types, and scenarios; discuss different forms of protection approaches, both proactive and reactive; and describe emerging attack modes, defenses, and future research pathways.
 

This paper addresses the potential danger using integrated circuits which contain malicious hardware modifications hidden in the silicon structure. A so called hardware Trojan may be added at several stages of the chip development process. This work concentrates on formal hardware Trojan detection during the design phase and highlights applied verification techniques. Selected methods are discussed and their combination used to increase an introduced “Trojan Assurance Level”.
 

The use of side-channel measurements and fingerprinting, in conjunction with statistical analysis, has proven to be the most effective method for accurately detecting hardware Trojans in fabricated integrated circuits. However, these post-fabrication trust evaluation methods overlook the capabilities of advanced design skills that attackers can use in designing sophisticated Trojans. To this end, we have designed a Trojan using power-gating techniques and demonstrate that it can be masked from advanced side-channel fingerprinting detection while dormant. We then propose a real-time trust evaluation framework that continuously monitors the on-board global power consumption to monitor chip trustworthiness. The measurements obtained corroborate our frameworks effectiveness for detecting Trojans. Finally, the results presented are experimentally verified by performing measurements on fabricated Trojan-free and Trojan-infected variants of a reconfigurable linear feedback shift register (LFSR) array.

Due to design and fabrication outsourcing to foundries, the problem of malicious modifications to integrated circuits known as hardware Trojans has attracted attention in academia as well as industry. To reduce the risks associated with Trojans, researchers have proposed different approaches to detect them. Among these approaches, test-time detection approaches have drawn the greatest attention and most approaches assume the existence of a “golden model”. Prior works suggest using reverse-engineering to identify such Trojan-free ICs for the golden model but they did not state how to do this efficiently. In this paper, we propose an innovative and robust reverseengineering approach to identify the Trojan-free ICs. We adapt a well-studied machine learning method, one-class support vector machine, to solve our problem. Simulation results using state-of-the-art tools on several publicly available circuits show that our approach can detect hardware Trojans with high accuracy rate across different modeling and algorithm parameters.

This paper discusses the detection of hardware Trojans (HTs) by their breaking of symmetries within integrated circuits (ICs), as measured by path delays. Typically, path delay or side channel methods rely on comparisons to a golden, or trusted, sample. However, golden standards are affected by inter-and intra-die variations which limit the confidence in such comparisons. Symmetry is a way to detect modifications to an IC with increased confidence by confirming subcircuit consistencies within as it was originally designed. The difference in delays from a given path to a set of symmetric paths will be the same unless an inserted HT breaks symmetry. Symmetry can naturally exist in ICs or be artificially added. We describe methods to find and measure path delays against symmetric paths, as well as the advantages and disadvantages of this method. We discuss results of examples from benchmark circuits demonstrating the detection of hardware Trojans.
 

Malicious hardware is a realistic threat. It can be possible to insert the malicious functionality on a device as deep as in the hardware design flow, long before manufacturing the silicon product. Towards developing a hardware Trojan horse detection methodology, we analyze capabilities and limitations of existing techniques, framing a testing strategy for uncovering efficiently hardware Trojan horses in mass-produced integrated circuits.
 

An application of two Cyber-Physical System (CPS) security countermeasures - Intelligent Checker (IC) and Cross-correlator - for enhancing CPS safety and achieving required CPS safety integrity level is presented. ICs are smart sensors aimed at detecting attacks in CPS and alerting the human operators. Cross-correlator is an anomaly detection technique for detecting deception attacks. We show how ICs could be implemented at three different CPS safety protection layers to maintain CPS in a safe state. In addition, we combine ICs with the cross-correlator technique to assure high probability of failure detection. Performance simulations show that a combination of these two security countermeasures is effective in detecting and mitigating CPS failures, including catastrophic failures.
 

Probing attacks are serious threats on integrated circuits. Security products often include a protective layer called shield that acts like a digital fence. In this article, we demonstrate a new shield structure that is cryptographically secure. This shield is based on the newly proposed SIMON lightweight block cipher and independent mesh lines to ensure the security against probing attacks of the hardware located behind the shield. Such structure can be proven secure against state-of-the-art invasive attacks. For the first time in the open literature, we describe a chip designed with a digital shield, and give an extensive report of its cost, in terms of power, metal layer(s) to sacrifice and of logic (including the logic to connect it to the CPU). Also, we explain how “Through Silicon Vias” (TSV) technology can be used for the protection against both frontside and backside probing.

Radio Frequency IDentification (RFID) is a technique for speedy and proficient identification system, it has been around for more than 50 years and was initially developed for improving warfare machinery. RFID technology bridges two technologies in the area of Information and Communication Technologies (ICT), namely Product Code (PC) technology and Wireless technology. This broad-based rapidly expanding technology impacts business, environment and society. The operating principle of an RFID system is as follows. The reader starts a communication process by radiating an electromagnetic wave. This wave will be intercepted by the antenna of the RFID tag, placed on the item to be identified. An induced current will be created at the tag and will activate the integrated circuit, enabling it to send back a wave to the reader. The reader redirects information to the host where it will be processed. RFID is used for wide range of applications in almost every field (Health, education, industry, security, management ...). In this review paper, we will focus on agricultural and environmental applications.

Hardware Trojan Threats (HTTs) are stealthy components embedded inside integrated circuits (ICs) with an intention to attack and cripple the IC similar to viruses infecting the human body. Previous efforts have focused essentially on systems being compromised using HTTs and the effectiveness of physical parameters including power consumption, timing variation and utilization for detecting HTTs. We propose a novel metric for hardware Trojan detection coined as HTT detectability metric (HDM) that uses a weighted combination of normalized physical parameters. HTTs are identified by comparing the HDM with an optimal detection threshold; if the monitored HDM exceeds the estimated optimal detection threshold, the IC will be tagged as malicious. As opposed to existing efforts, this work investigates a system model from a designer perspective in increasing the security of the device and an adversary model from an attacker perspective exposing and exploiting the vulnerabilities in the device. Using existing Trojan implementations and Trojan taxonomy as a baseline, seven HTTs were designed and implemented on a FPGA testbed; these Trojans perform a variety of threats ranging from sensitive information leak, denial of service to beat the Root of Trust (RoT). Security analysis on the implemented Trojans showed that existing detection techniques based on physical characteristics such as power consumption, timing variation or utilization alone does not necessarily capture the existence of HTTs and only a maximum of 57% of designed HTTs were detected. On the other hand, 86% of the implemented Trojans were detected with HDM. We further carry out analytical studies to determine the optimal detection threshold that minimizes the summation of false alarm and missed detection probabilities.

Physical attacks against cryptographic devices typically take advantage of information leakage (e.g., side-channels attacks) or erroneous computations (e.g., fault injection attacks). Preventing or detecting these attacks has become a challenging task in modern cryptographic research. In this context intrinsic physical properties of integrated circuits, such as Physical(ly) Unclonable Functions (PUFs), can be used to complement classical cryptographic constructions, and to enhance the security of cryptographic devices. PUFs have recently been proposed for various applications, including anti-counterfeiting schemes, key generation algorithms, and in the design of block ciphers. However, currently only rudimentary security models for PUFs exist, limiting the confidence in the security claims of PUF-based security primitives. A useful model should at the same time (i) define the security properties of PUFs abstractly and naturally, allowing to design and formally analyze PUF-based security solutions, and (ii) provide practical quantification tools allowing engineers to evaluate PUF instantiations. In this paper, we present a formal foundation for security primitives based on PUFs. Our approach requires as little as possible from the physics and focuses more on the main properties at the heart of most published works on PUFs: robustness (generation of stable answers), unclonability (not provided by algorithmic solutions), and unpredictability. We first formally define these properties and then show that they can be achieved by previously introduced PUF instantiations. We stress that such a consolidating work allows for a meaningful security analysis of security primitives taking advantage of physical properties, becoming increasingly important in the development of the next generation secure information systems.