Biblio

Cryptographic (crypto) algorithms are the essential ingredients of all secure systems: crypto hash functions and encryption algorithms, for example, can guarantee properties such as integrity and confidentiality. Developers, however, can misuse the application programming interfaces (API) of such algorithms by using constant keys and weak passwords. This paper presents CRYLOGGER, the first open-source tool to detect crypto misuses dynamically. CRYLOGGER logs the parameters that are passed to the crypto APIs during the execution and checks their legitimacy offline by using a list of crypto rules. We compared CRYLOGGER with CryptoGuard, one of the most effective static tools to detect crypto misuses. We show that our tool complements the results of CryptoGuard, making the case for combining static and dynamic approaches. We analyzed 1780 popular Android apps downloaded from the Google Play Store to show that CRYLOGGER can detect crypto misuses on thousands of apps dynamically and automatically. We reverse-engineered 28 Android apps and confirmed the issues flagged by CRYLOGGER. We also disclosed the most critical vulnerabilities to app developers and collected their feedback.

The large amount of third-party packages available in fast-moving software ecosystems, such as Node.js/npm, enables attackers to compromise applications by pushing malicious updates to their package dependencies. Studying the npm repository, we observed that many packages in the npm repository that are used in Node.js applications perform only simple computations and do not need access to filesystem or network APIs. This offers the opportunity to enforce least-privilege design per package, protecting applications and package dependencies from malicious updates. We propose a lightweight permission system that protects Node.js applications by enforcing package permissions at runtime. We discuss the design space of solutions and show that our system makes a large number of packages much harder to be exploited, almost for free.

The evolution of power system as a smart grid (SG) not only has enhanced the monitoring and control capabilities of the power grid, but also raised its security concerns and vulnerabilities. With a boom in Internet of Things (IoT), a lot a sensors are being deployed across the grid. This has resulted in huge amount of data available for processing and analysis. Machine learning (ML) and deep learning (DL) algorithms are being widely used to extract useful information from this data. In this context, this paper presents a comprehensive literature survey of different ML and DL techniques that have been used in the smart grid cyber security area. The survey summarizes different type of cyber threats which today's SGs are prone to, followed by various ML and DL-assisted defense strategies. The effectiveness of the ML based methods in enhancing the cyber security of SGs is also demonstrated with the help of a case study.

This paper presents a hardware-in-the-loop cyber-physical system architecture design to monitor and control smart lights connected to the active distribution grid. The architecture uses Zigbee-based (IEEE 802.15.4) wireless sensor networks and publish-subscribe architecture to exchange monitoring and control signals between smart-light actuators (SLAs) and a smart-light central controller (SLCC). Each SLA integrated into a smart light consists of a Zigbee-based endpoint module to send and receive signals to and from the SLCC. The SLCC consists of a Zigbee-based coordinator module, which further exchanges the monitoring and control signals with the active distribution management system over the TCP/IP communication network. The monitoring signals from the SLAs include light status, brightness level, voltage, current, and power data, whereas, the control signals to the SLAs include light intensity, turn ON, turn OFF, standby, and default settings. We have used our existing hardware-in-the-loop (HIL) cyber-physical system (CPS) security SCADA testbed to process signals received from the SLCC and respond suitable control signals based on the smart light schedule requirements, system operation, and active distribution grid dynamic characteristics. We have integrated the proposed cyber-physical smart light control system (CPSLCS) testbed to our existing HIL CPS SCADA testbed. We use the integrated testbed to demonstrate the efficacy of the proposed algorithm by real-time performance and latency between the SLCC and SLAs. The experiments demonstrated significant results by 100% realtime performance and low latency while exchanging data between the SLCC and SLAs.

Smart substation and Vehicular Ad-Hoc Network (VANET) are two important applications of aggregate signature scheme. Due to the large number of data collection equipment in substation, it needs security authentication and integrity protection to transmit data. Similarly, in VANET, due to limited resources, it has the needs of privacy protection and improving computing efficiency. Aggregate signature scheme can satisfy the above these needs and realize one-time verification of signature for multi-terminal data collection which can improve the performance. Aggregate signature scheme is an important technology to solve network security problem. Recently, many aggregate signature schemes are proposed which can be applied in smart grid or VANET. In this paper, we present two security analyses on two aggregate signature schemes proposed recently. By analysis, it shows that the two aggregate signature schemes do not satisfy the security property of unforgeability. A malicious user can forge a signature on any message. We also present some improved methods to solve these security problems with better performance. From security analysis to improvement of aggregate signature scheme, it is very suitable to be an instance to exhibit the students on designing of security aggregate signature scheme for network security education or course.

The desired features for the smart grid include dynamic billing capabilities along with consumer privacy protection. Existing aggregation-based privacy frameworks have limitations such as centralized designs prone to single points of failure and/or a high computational overload on the smart meters due to in-network aggregation or complex algorithmic operations. Additionally, these existing schemes do not consider how dynamic billing can be implemented while consumer privacy is preserved. In this paper, a cyber-resilient framework that enables dynamic billing while focusing on consumer privacy preservation is proposed. The distributed design provides a framework for spatio-temporal aggregation and keeps the process lightweight for the smart meters. The comparative analysis of our proposed work with existing work shows a significant improvement in terms of the spatial aggregation overhead, overhead on smart meters and scalability. The paper also discusses the resilience of our framework against privacy attacks.

The following topics are dealt with: diseases; medical signal processing; learning (artificial intelligence); security of data; blood; patient treatment; patient monitoring; bioelectric phenomena; biomedical electrodes; biological tissues.

Classification between machine-translated text and original text are often tokenized on vocabulary of the corpi. With N-grams larger than uni-gram, one can create a model that estimates a decision boundary based on word frequency probability distribution; however, this approach is exponentially expensive because of high dimensionality and sparsity. Instead, we let samples of the corpi be represented by part-of-speech tagging which is significantly less vocabulary. With less trigram permutations, we can create a model with its tri-gram frequency probability distribution. In this paper, we explore less conventional ways of approaching techniques for handling documents, dictionaries, and the likes.

Scientific publications are an essential resource for detecting emerging trends and innovations in a very early stage, by far earlier than patents may allow. Thereby Visual Analytics systems enable a deep analysis by applying commonly unsupervised machine learning methods and investigating a mass amount of data. A main question from the Visual Analytics viewpoint in this context is, do abstracts of scientific publications provide a similar analysis capability compared to their corresponding full-texts? This would allow to extract a mass amount of text documents in a much faster manner. We compare in this paper the topic extraction methods LSI and LDA by using full text articles and their corresponding abstracts to obtain which method and which data are better suited for a Visual Analytics system for Technology and Corporate Foresight. Based on a easy replicable natural language processing approach, we further investigate the impact of lemmatization for LDA and LSI. The comparison will be performed qualitative and quantitative to gather both, the human perception in visual systems and coherence values. Based on an application scenario a visual trend analytics system illustrates the outcomes.

Fueled by the emergence of IoT-enabled medical sensors and big data analytics, nations all over the world are widely adopting digitalization of healthcare systems. This is certainly a positive trend for improving the entire spectrum of quality of care, but this convenience is also posing a huge challenge on the security of healthcare data. For ensuring privacy and protection of healthcare data, access control is regarded as one of the first-line-of-defense mechanisms. As none of the traditional enterprise access control models can completely cater to the need of the healthcare domain which includes a myriad of contexts, in this paper, we present a context-policy-based access control scheme. Our scheme relies on the eTRON cybersecurity architecture for tamper-resistance and cryptographic functions, and leverages a context-specific blend of classical discretionary and role-based access models for incorporation into legacy systems. Moreover, our scheme adheres to key recommendations of prominent statutory and technical guidelines including HIPAA and HL7. The protocols involved in the proposed access control system have been delineated, and a proof-of-concept implementation has been carried out - along with a comparison with other systems, which clearly suggests that our approach is more responsive to different contexts for protecting healthcare data.

Security vetting of Android applications is one of the crucial aspects of the Android ecosystem. Regarding the state of the art tools for this goal, most of them doesn't consider analyzing native codes and only analyze the Java code. However, Android concedes its developers to implement a part or all of their applications using C or C++ code. Thus, applying conservative manners for analyzing Android applications while ignoring native codes would lead to less precision in results. Few works have tried to analyze Android native codes, but only JN-SAF has applied taint analysis using static techniques such as symbolic execution. However, symbolic execution has some problems when is used in large programs. One of these problems is the exponential growth of program paths that would raise the path explosion issue. In this work, we have tried to alleviate this issue by introducing our new tool named CTAN. CTAN applies new symbolic execution methods to angr in a particular way that it can make JN-SAF more efficient and faster. We have introduced compositional taint analysis in CTAN by combining satisfiability modulo theories with symbolic execution. Our experiments show that CTAN is 26 percent faster than its previous work JN-SAF and it also leads to more precision by detecting more data-leakage in large Android native codes.

Phasor measurement unit (PMU) networks are increasingly deployed to offer timely and high-precision measurement of today's highly interconnected electric power systems. To enhance the cyber-resilience of PMU networks against malicious attacks and system errors, we develop an optimization-based network management scheme based on the software-defined networking (SDN) communication infrastructure to recovery PMU network connectivity and restore power system observability. The scheme enables fast network recovery by optimizing the path generation and installation process, and moreover, compressing the SDN rules to be installed on the switches. We develop a prototype system and perform system evaluation in terms of power system observability, recovery speed, and rule compression using the IEEE 30-bus system and IEEE 118-bus system.

The Internet of Things (IoT) has enabled the rapid pace of the use of communication technology and infiltration of technical systems in a digital world. In terms of power systems generation and operation, a reliable solution for substation automation and smart grid communication is the IEC 61850 standard. It has a robust modelling structure for monitoring, protection, and control and management systems in substations and across the grid. Modern communication technologies are destined for internet use for remote monitoring, settings, and data recovery. However, the communication network is exposed to cyber threats and evident risks in security defense of automated power systems. To tackle these vulnerabilities, the IEC 62351 standard aims to improve security in handling the communication and data transfers in power system automation. This paper discusses the different security measures in communication, information and cyber security solutions in power systems. To further illustrate the novel communication and security schemes of digital substations, a case study using the Victoria University Zone Substation (VUZS) simulator for cybersecurity assessment has been instigated.

Reliable group communication is an important cornerstone for various applications in the domain of Industrial Internet of Things (IIoT). Yet, despite various proposals, state-of- the-art (open) protocol stacks for IPv6-enabled Low Power and Lossy Networks (LLNs) have little to offer, regarding standardized or agreed-upon protocols for correct multicast routing, not to mention reliable multicast. We present an informal computational model, which allows us to analyze the respective candidates for multicast routing. Further, we focus on the IEEE 802.15.4/6LoWPAN stack and discuss prominent multicast routing protocols and how they fit into this model.

Fast Growth of (ICT) Information and Communication Technology results to Innovation of Cloud Computing and is considered as a key driver for technological innovations, as an IT innovations, cloud computing had added a new dimension to that importance by increasing usage to technology that motivates economic development at the national and global levels. Continues need of higher storage space (applications, files, videos, music and others) are some of the reasons for adoption and implementation, Users and Enterprises are gradually changing the way and manner in which Data and Information are been stored. Storing/Retrieving Data and Information traditionally using Standalone Computers are no longer sustainable due to high cost of Peripheral Devices, This further recommends organizational innovative adoption with regards to approaches on how to effectively reduced cost in businesses. Cloud Computing provides a lot of prospects to users/organizations; it also exposes security concerns which leads to low adoption, implementation and usage. Therefore, the study will examine standard ways of improving cloud computing adoption, implementation and usage by proposing and developing a security model using a design methodology that will ensure a secured Cloud Computing and also identify areas where future regularization could be operational.

Cross-term interference exists in the WVD of multi-component signals in time-frequency analysis, and the STFT is limited by Heisenberg uncertainty criterion. For multicomponent signals under noisy background, this paper proposes an improved STFT-Wigner algorithm, which establishes a threshold based on the exponential multiplication result compared to the original algorithm, so as to weaken the cross term and reduce the impact of noise on the signal, and improve the time-frequency aggregation of the signal. Simulation results show that the improved algorithm has higher time-frequency aggregation than other methods. Similarly, for cross-term suppression, our method is superior to many other TF analysis methods in low signal-to-noise ratio (SNR) environment.

The present-day world has become all dependent on cyberspace for every aspect of daily living. The use of cyberspace is rising with each passing day. The world is spending more time on the Internet than ever before. As a result, the risks of cyber threats and cybercrimes are increasing. The term `cyber threat' is referred to as the illegal activity performed using the Internet. Cybercriminals are changing their techniques with time to pass through the wall of protection. Conventional techniques are not capable of detecting zero-day attacks and sophisticated attacks. Thus far, heaps of machine learning techniques have been developed to detect the cybercrimes and battle against cyber threats. The objective of this research work is to present the evaluation of some of the widely used machine learning techniques used to detect some of the most threatening cyber threats to the cyberspace. Three primary machine learning techniques are mainly investigated, including deep belief network, decision tree and support vector machine. We have presented a brief exploration to gauge the performance of these machine learning techniques in the spam detection, intrusion detection and malware detection based on frequently used and benchmark datasets.

Trust is essential in designing autonomous and semiautonomous Robots and Autonomous Systems (RAS), because of the ``No trust, no use'' concept. RAS should provide high quality services, with four key properties that make them trustworthy: they must be (i) robust with regards to any system health related issues, (ii) safe for any matters in their surrounding environments, (iii) secure against any threats from cyber spaces, and (iv) trusted for human-machine interaction. This article thoroughly analyses the challenges in implementing the trustworthy RAS in respects of the four properties, and addresses the power of AI in improving the trustworthiness of RAS. While we focus on the benefits that AI brings to human, we should realize the potential risks that could be caused by AI. This article introduces for the first time the set of key aspects of human-centered AI for RAS, which can serve as a cornerstone for implementing trustworthy RAS by design in the future.

The environment of wireless sensor networks (WSNs) makes the communication not only have the broadcast nature of wireless transmission, but also be limited to the low power and communication capability of sensor equipment. Both of them make it hard to ensure the confidentiality of communication. In this paper, we propose a cluster-based cooperative jamming scheme based on physical layer security for WSNs. The mathematical principle of the scheme is based on the design principle of code division multiple access. By using the orthogonality of orthogonal vectors, the legitimate receiver can effectively eliminate the noise, which is generated by the cooperative jamming nodes to disturb the eavesdropper. This scheme enables the legitimate receiver to ensure a strong communication confidentiality even if there is no location or channel advantage comparing with eavesdroppers. Through extensive simulations, the security performance of the proposed scheme is investigated in terms of secrecy rate.

The Internet of Things (IoT) has been one of the biggest revelations of the last decade. These cyber-physical systems seamlessly integrate and improve the activities in our daily lives. Hence, creating a wide application for it in several domains, such as smart buildings and cities. However, the integration of IoT also comes with privacy challenges. The privacy challenges result from the ability of these devices to pervasively collect personal data about individuals through sensors in ways that could be unknown to them. A number of research efforts have evaluated privacy policy awareness and enforcement as key components for addressing these privacy challenges. This paper provides a framework for understanding contextualized privacy policy within the IoT domain. This will enable IoT privacy researchers to better understand IoT privacy policies and their modeling.

Power systems automation and communication standards are crucial for the transition of the conventional power system towards a smart grid. The IEC 61850 standard is widely used for substation automation and protection. It enables real-time communication and data exchange between critical substation automation devices. IEC 61850 serves as the foundation for open communication and data exchange for digital substations of the smart grid. However, IEC 61850 has cyber security vulnerabilities that can be exploited with a man-in-the-middle attack. Such coordinated cyber attacks against the protection system in digital substations can disconnect generation and transmission lines, causing cascading failures. In this paper, we demonstrate a cyber attack involving the Generic Object-Oriented Substation Event (GOOSE) protocol of IEC 61850. This is achieved by exploiting the cyber security vulnerabilities in the protocol and injecting spoofed GOOSE data frames into the substation communication network at the bay level. The cyber attack leads to tripping of multiple protective relays in the power grid, eventually resulting in a blackout. The attack model and impact on system dynamics are verified experimentally through hardware-in-the-loop simulations using commercial relays and Real-Time Digital Simulator (RTDS).

Power system automation and communication standards are spearheading the power system transition towards a smart grid. IEC 61850 is one such standard, which is widely used for substation automation and protection. It enables real-time communication and data exchange between critical substation automation and protection devices within digital substations. However, IEC 61850 is not cyber secure. In this paper, we demonstrate the dangerous implications of not securing IEC 61850 standard. Cyber attacks may exploit the vulnerabilities of the Sampled Values (SV) and Generic Object-Oriented Substation Event (GOOSE) protocols of IEC 61850. The cyber attacks may be realised by injecting spoofed SV and GOOSE data frames into the substation communication network at the bay level. We demonstrate that such cyber attacks may lead to obstruction or tripping of multiple protective relays. Coordinated cyber attacks against the protection system in digital substations may cause generation and line disconnections, triggering cascading failures in the power grid. This may eventually result in a partial or complete blackout. The attack model, impact on system dynamics and cascading failures are veri ed experimentally through a proposed cyber-physical experimental framework that closely resembles real-world conditions within a digital substation, including Intelligent Electronic Devices (IEDs) and protection schemes. It is implemented through Hardware-in-the-Loop (HIL) simulations of commercial relays with a Real-Time Digital Simulator (RTDS).

Most of today's infrastructure systems can be efficiently operated thanks to the intelligent power supply of the smart grids. However, smart grids are highly vulnerable to malicious attacks, that is, because of the interplay between the components in the smart grids, the failure of some critical components may result in the cascading failure and breakdown of the whole system. Therefore, the question of how to identify the most critical components to protect the smart grid system is the first challenge to operators. To enable the system's robustness, there has been a lot of effort aimed at the system analysis, designing new architectures, and proposing new algorithms. However, these works mainly introduce different ranking methods for link (transmission line) or node (station) identification and directly select most the highest degree nodes or common links as the critical ones. These methods fail to address the problem of interdependencies between components nor consider the role of users that is one of critical factors impacting on the smart grid vulnerability assessment. This motivates us to study a more general and practical problem in terms of smart grid vulnerability assessment, namely the Maximum-Impact through Critical-Line with Limited Budget (MICLLB) problem. The objective of this research is to provide an efficient method to identify critical components in the system by considering a realistic attack scenario.

In this paper, we observed Continuous Attacks are one kind of common side channel attack scenarios, where an adversary frequently probes the same target cache lines in a short time. Continuous Attacks cause target cache lines to go through multiple load-evict processes, exhibiting Ping-Pong Patterns. Identifying and obscuring Ping-Pong Patterns effectively interferes with the attacker's probe and mitigates Continuous Attacks. Based on the observations, this paper proposes Ping-Pong Regulator to identify multiple Ping-Pong Patterns and block them with different strategies (Preload or Lock). The Preload proactively loads target lines into the cache, causing the attacker to mistakenly infer that the victim has accessed these lines; the Lock fixes the attacked lines' directory entries on the last level cache directory until they are evicted out of caches, making an attacker's observation of the locked lines is always the L2 cache miss. The experimental evaluation demonstrates that the Ping-Pong Regulator efficiently identifies and secures attacked lines, induces negligible performance impacts and storage overhead, and does not require any software support.

Fault attacks consist in changing the program behavior by injecting faults at run-time, either at hardware or at software level. Their goal is to change the correct progress of the algorithm and hence, either to allow gaining some privilege access or to allow retrieving some secret information based on an analysis of the deviation of the corrupted behavior with respect to the original one. Countermeasures have been proposed to protect embedded systems by adding spatial, temporal or information redundancy at hardware or software level. First we define Countermeasures Check Point (CCP) and CCPs-based countermeasures as an important subclass of countermeasures. Then we propose a methodology to generate an optimal protection scheme for CCPs-based countermeasure. Finally we evaluate our work on a benchmark of code examples with respect to several Control Flow Integrity (CFI) oriented existing protection schemes.