Biblio

In proof-of-stake (PoS) blockchains, stakeholders that extend the chain are selected according to the amount of stake they own. In S&P 2019 the "Ouroboros Crypsinous" system of Kerber et al. (and concurrently Ganesh et al. in EUROCRYPT 2019) presented a mechanism that hides the identity of the stakeholder when adding blocks, hence preserving anonymity of stakeholders both during payment and mining in the Ouroboros blockchain. They focus on anonymizing the messages of the blockchain protocol, but suggest that potential identity leaks from the network-layer can be removed as well by employing anonymous broadcast channels.In this work we show that this intuition is flawed. Even ideal anonymous broadcast channels do not suffice to protect the identity of the stakeholder who proposes a block.We make the following contributions. First, we show a formal network-attack against Ouroboros Crypsinous, where the adversary can leverage network delays to distinguish who is the stakeholder that added a block on the blockchain. Second, we abstract the above attack and show that whenever the adversary has control over the network delay – within the synchrony bound – loss of anonymity is inherent for any protocol that provides liveness guarantees. We do so, by first proving that it is impossible to devise a (deterministic) state-machine replication protocol that achieves basic liveness guarantees and better than (1-2f) anonymity at the same time (where f is the fraction of corrupted parties). We then connect this result to the PoS setting by presenting the tagging and reverse tagging attack that allows an adversary, across several executions of the PoS protocol, to learn the stake of a target node, by simply delaying messages for the target. We demonstrate that our assumption on the delaying power of the adversary is realistic by describing how our attack could be mounted over the Zcash blockchain network (even when Tor is used). We conclude by suggesting approaches that can mitigate such attacks.

As an innovative type of decentralized model, blockchain is a growing list of blocks linked by cryptography. Blockchain incorporates anonymity protocol, distributed data storage, consensus algorithm, and smart contract. The anonymity protocols in blockchain are significant in that they could protect users from leaking their personal information. In this paper, we will conduct a detailed review and comparison of anonymity protocols used in three famous cryptocurrencies, namely Bitcoin, Zcash, and Ethereum.

Today we live in a hyper-connected world, where a large amount of applications and services are supported by ad hoc networks. They have a decentralized management, are flexible and versatile but their characteristics are in turn their main weaknesses. This work introduces a preliminary analysis of the evolution, trends and the state of the art in the context of the security in ad hoc networks. To this end, two different methodologies are applied: a bibliometric analysis and a Systematic Literature Review. Results show that security in MANETs and VANETs are still an appealing research field. In addition, we realized that there is no clear separation of solutions by line of defense. This is because they are sometimes misclassified by the authors or simply there is no line of defense that totally fit well with the proposed solution. Because of that, new taxonomies including novel definitions of lines of defense are needed. In this work, we propose the use of tolerant or survivable solutions which are the ones that preserve critical system or network services in presence of fault, malfunctions or attacks.

Malware classification is a problem of great significance in the domain of information security. This is because the classification of malware into respective families helps in determining their intent, activity, and level of threat. In this paper, we propose a novel deep learning approach to malware classification. The proposed method converts malware executables into image-based representations. These images are then classified into different malware families using an autoencoder enhanced deep convolutional neural network (AE-DCNN). In particular, we propose a novel training mechanism wherein a DCNN classifier is trained with the help of an encoder. We conjecture that using an encoder in the proposed way provides the classifier with the extra information that is perhaps lost during the forward propagation, thereby leading to better results. The proposed approach eliminates the use of feature engineering, reverse engineering, disassembly, and other domain-specific techniques earlier used for malware classification. On the standard Malimg dataset, we achieve a 10-fold cross-validation accuracy of 99.38% and F1-score of 99.38%. Further, due to the texture-based analysis of malware files, the proposed technique is resilient to several obfuscation techniques.

With the rapid growth of the Internet of Things (IoT) applications in smart regions/cities, for example, smart healthcare, smart homes/offices, there is an increase in security threats and risks. The IoT devices solve real-world problems by providing real-time connections, data and information. Besides this, the attackers can tamper with sensors, add or remove them physically or remotely. In this study, we address the IoT security sensor tampering issue in an office environment. We collect data from real-life settings and apply machine learning to detect sensor tampering using two methods. First, a real-time view of the traffic patterns is considered to train our isolation forest-based unsupervised machine learning method for anomaly detection. Second, based on traffic patterns, labels are created, and the decision tree supervised method is used, within our novel Anomaly Detection using Machine Learning (AD-ML) system. The accuracy of the two proposed models is presented. We found 84% with silhouette metric accuracy of isolation forest. Moreover, the result based on 10 cross-validations for decision trees on the supervised machine learning model returned the highest classification accuracy of 91.62% with the lowest false positive rate.

6G is the next generation for the communication systems. In recent years, machine learning algorithms have been applied widely in various fields such as health, transportation, and the autonomous car. The predictive algorithms will be used in 6G problems. With the rapid developments of deep learning techniques, it is critical to take the security concern into account when applying the algorithms. While machine learning offers significant advantages for 6G, AI models’ security is normally ignored. Due to the many applications in the real world, security is a vital part of the algorithms. This paper proposes a mitigation method for adversarial attacks against proposed 6G machine learning models for the millimeter-wave (mmWave) beam prediction using adversarial learning. The main idea behind adversarial attacks against machine learning models is to produce faulty results by manipulating trained deep learning models for 6G applications for mmWave beam prediction. We also present the adversarial learning mitigation method’s performance for 6G security in millimeter-wave beam prediction application with fast gradient sign method attack. The mean square errors of the defended model under attack are very close to the undefended model without attack.

As AI technology advances and its use increases, efforts to incorporate machine learning for malware detection are increasing. However, for malware learning, a standardized data set is required. Because malware is unstructured data, it cannot be directly learned. In order to solve this problem, many studies have attempted to convert unstructured data into structured data. In this study, the features and limitations of each were analyzed by investigating and analyzing the method of converting unstructured data proposed in each study into structured data. As a result, most of the data conversion techniques suggest conversion mechanisms, but the scope of each technique has not been determined. The resulting data set is not suitable for use as training data because it has infinite properties.

Usually on the top of Smart Chip covered with active shielding layer to prevent invasive physical exploration tampering attacks on part of the chip's function modules, to obtain the chip's critical storage data and sensitive information. This paper introduces a design based on UMC55 technology, and applied to the safety chip active shielding layer method for layout design, the layout design from the two aspects of the metal shielding line and shielding layer detecting circuit, using the minimum size advantage and layout design process when the depth of hidden shielding line interface and port order connection method and greatly increased the difficulty of physical attack. The layout design can withstand most of the current FIB physical attack technology, and has been applied to the actual smart card design, and it has important practical significance for the security design and attack of the chip.

The use of mobile devices has increased dramatically in recent years. These smart devices allow us to easily perform many functions such as e-mail, internet, Bluetooth, SMS and MMS without restriction of time and place. Thus, these devices have become an indispensable part of our lives today. Due to this high usage, malware developers have turned to this platform and many mobile malware has emerged in recent years. Many security companies and experts have developed methods to protect our mobile devices. In this study, in order to contribute to mobile malware detection and analysis, an application has been implemented that automatically injects payload into normal apk. With this application, it is aimed to create a data set that can be used by security companies and experts.

Along with the advance of science and technology, informationization society construction is gradually perfect. The development of modern information technology has driven the growth of the entire network spatial data, and network security is a matter of national security. There are several countries included in the national security strategy, with the increase of network space connected point, traditional network security space processing way already cannot adapt to the demand. Machine learning can effectively solve the problem of network security. Around the machine learning technology applied in the field of network security research results, this paper introduces the basic concept of network security situational awareness system, the basic model, and system framework. Based on machine learning, this paper elaborates the network security situation awareness technology, including data mining technology, feature extraction technology and situation prediction technology. Recursive feature elimination, decision tree algorithm, support vector machine, and future research direction in the field of network security situational awareness are also discussed.

The power communication network generates a large amount of data. The existing security monitoring method needs to use a large transmission bandwidth in the process of data processing, which leads to the decrease of real-time response. Therefore, an automatic monitoring method of power communication network security based on edge computing is proposed. The paper establishes the power communication monitoring network architecture by combining RFID identification sensor network and wireless communication network. The edge calculation is embedded to the edge side of the power communication network, and the data processing model of power communication is established. Based on linear discriminant analysis, the paper designs a network security situation awareness assessment model, and uses this model to evaluate the real-time data collected by the power communication network. According to the evaluation results, the probability of success of intrusion attack is calculated and the security risk monitoring is carried out for the intrusion attack. The experimental results show that compared with the existing monitoring methods, the edge based security monitoring method can effectively reduce communication delay, improve the real-time response, and then improve the intelligent level of power communication network.

The mishandled passenger baggage in aviation industry is still a big problem. This research is focused on designing a baggage handling system (BHS) at the airport for identifying and tracking of passenger baggage based on RFID technology. The proposed BHS system consists of hardware device to identify the baggage and the cloud-based tracking application. The BHS device is designed based on UHF passive RFID technology and IoT technology. The device can be used as handheld device in check-in counter and arrival area. The device can also be used as a fixed device in screening, sortation, and transition belt conveyer. The BHS device consists of RFID reader module, a microcontroller, LCD, keypad, a WiFi module and a storage device. The user and airport staff can track the luggage position and its status through dashboard application.

Rapid multiplication of electric vehicles requires the implementation of a new infrastructure to sustain their operations. For instance, charging these vehicles batteries necessitates a connection that allows information exchanges between vehicle and infrastructure. These exchanges are managed by a network called V2G (Vehicle to Grid), which is governed by the ISO 15118 standard. This last recommends the use of X.509 hierarchical PKI to protect the network communications against attacks. Although several authors have identified and criticized the shortcomings of this proposal, but no one provides a robust and effective remedial solution to alleviate them. This paper proposes an efficient protocol that addresses these shortcomings while respecting the concepts of the ISO 15118 standard. It fulfills the most important security requirements i.e. confidentiality, anonymity, integrity and non-repudiation. The validity and effectiveness of the proposed protocol were confirmed using the formal modeling tool Tamarin Prover and the RISE- V2G simulator.

In recent years, there have been situations in which the zero-sequence protection of the transformer has been incorrectly operated due to the converter transformer energizing or fault recovery. For converter transformers, maloperation may also occur. However, there is almost no theoretical research on the zero-mode inrush currents of converter transformers. This paper studies the characteristics of the zero-mode inrush currents of the converter transformers, including the relationship between the amplitude and attenuation characteristics of the zero-mode inrush currents of converter transformers, and their relationship with the system resistance, remanence, and closing angle. First, based on the T-type equivalent circuit of the transformer, the equivalent circuit of the zero-mode inrush current of each transformer is obtained. On this basis, the amplitude relationship of the zero-mode inrush currents of different converter transformers is obtained: the zero-mode inrush current of the energizing pole YY transformer becomes larger than the YD transformer, the energized pole YD becomes greater than the YY transformer, and the YY transformer zero-mode inrush current rises from 0. It is also analyzed that the sympathetic interaction will make the attenuation of the converter transformer zero-mode inrush current slower. The system resistance mainly affects the initial attenuation speed, and the later attenuation speed is mainly determined by the converter transformer leakage reactance. Finally, PSCAD modeling and simulation are carried out to verify the accuracy of the theoretical analysis.

Advances in artificial intelligence, machine learning, and robotics have profoundly impacted the field of autonomous navigation and driving. However, sensor spoofing attacks can compromise critical components and the control mechanisms of mobile robots. Therefore, understanding vulnerabilities in autonomous driving and developing countermeasures remains imperative for the safety of unmanned vehicles. Hence, we demonstrate cross-validation techniques for detecting spoofing attacks on the sensor data in autonomous driving in this work. First, we discuss how visual and inertial odometry (VIO) algorithms can provide a root-of-trust during navigation. Then, we develop examples for sensor data spoofing attacks using the open-source driving dataset. Next, we design an attack detection technique using VIO algorithms that cross-validates the navigation parameters using the IMU and the visual data. Following, we consider hardware-dependent attack survival mechanisms that support an autonomous system during an attack. Finally, we also provide an example of spoofing survival technique using on-board hardware oscillators. Our work demonstrates the applicability of classical mobile robotics algorithms and hardware security primitives in defending autonomous vehicles from targeted cyber attacks.

A good website quality is needed to meet user satisfaction. The value of the benefits of the web will be felt by many users if the web has very good quality. The ease of accessing the website is a reflection of the good quality of the website. The positive image of the web owner can be seen from the quality of the website. When doing research on the website of the Ministry of Agriculture, Directorate General of Food Crops, the researcher found several pages that did not meet the website category which were said to be of good quality. Based on these findings, the authors are interested in analyzing user satisfaction with the website to measure the quality of the website of the Ministry of Agriculture, Directorate General of Food Crops using the PIECES method (Performance, Information, Economy, Control/Security, Efficiency, Service). The results of the study indicate that the level of user satisfaction with the website has been indicated as SATISFIED on each indicator, however, in measuring the quality of the website using YSlow (the GTMetrix tools, Pingdom Website Speed Tools), and (Web of Trust) WOT found many deficiencies such as loading the website takes a long time, there are some pages that cannot be found (page not found) and so on. Therefore, the authors provide several recommendations for better website development.

Due to its minimal price and expandable wireless open system interconnection options for the coming years, wireless mesh networking is appealing, developing, and novel medium of speech, which is why it is becoming a somewhat widely used communication field. In all network types, one of the essential factors for prevalent and trustworthy communication is cybersecurity. The IEEE 802.11 working gathering has created various correspondence guidelines. Yet, they are by and by focusing on the 802.11s standard because of its dynamic setup and geography learning abilities. Information, voice, and directions are steered between hubs employing remote lattice organising. WMNs incidentally give nearby 802.11g admittance to customers and connection neighbours utilising 802.11a "backhaul," but this isn’t generally the situation because of changing requirements, for example, top information rate and inclusion range. The small cross-sectional organisation emerged as a fundamental innovation to enable broadband system management in large regions. It benefits specialised organisations by reducing the cost of sending networks and end customers by providing ubiquitous Internet access anywhere, anytime. Given the idea of wireless mesh networking and the lack of integrated organisational technology, small grid networks are powerless against malicious attacks. In the meantime, the limit of multi-radio multi-channel correspondence, the need for heterogeneous organisation coordination, and the interest for multi-bounce remote equality often render conventional security strategies ineffectual or challenging to carry out. Thus, wireless mesh networking presents new issues that require more viable and relevant arrangements. WMNs have piqued the curiosity of both scholastics and industry because of their promising future. Numerous testbeds are built for research purposes, and business items for veritable WMNs are accessible. Anyway, a few concerns should be cleared up before they can very well become widespread. For example, the accessible MAC and routing conventions are not customisable; the throughput drops impressively with an increasing number of hubs or bounces in WMNs. Because of the weakness of WMNs against various malicious attacks, the security and protection of correspondence is a serious concern. For example, enemies can sniff long-distance correspondence to obtain sensitive data. Attackers can carry out DoS attacks and control the substance of the information sent through compromised hubs, thereby endangering the company’s secret, accessibility authenticity, and integrity. WMNs, like compact Impromptu Organisations (MANETs), share a typical medium, no traffic aggregate point, and incredible topography. Due to these restrictions, normal safety frameworks in wired associations can’t be quickly applied to WMNs. Also, the techniques utilised in MANETs are not viable with WMNs. This is because of the manner in which WMNs expand MANETs in different ways. Framework centres are generally outfitted with an assortment of radios. Then, at that point, many channels are doled out to every centre to work with concurrent data move and diversity.

Research on post-quantum cryptography (PQC) to improve the security against quantum computers has been actively conducted. In 2020, NIST announced the final PQC candidates whose design rationales rely on NP-hard or NP-complete problems. It is believed that cryptography based on NP-hard problem might be secure against attacks using quantum computers. N. Koblitz introduced the concept of public-key cryptography using a 3-regular graph with a perfect dominating set in the 1990s. The proposed cryptosystem is based on NP-complete problem to find a perfect dominating set in the given graph. Later, S. Yoon proposed a variant scheme using a perfect minus dominating function. However, their works have not received much attention since these schemes produce huge ciphertexts and are hard to implement efficiently. Also, the security parameters such as key size and plaintext-ciphertext size have not been proposed yet. We conduct security and performance analysis of their schemes and discuss the practical range of security parameters. As an application, the scheme with one-wayness property can be used as an encoding method in the white-box cryptography (WBC).

Generative Adversarial Network (GAN) models have been widely used in various fields. More recently, styleGAN and styleGAN2 have been developed to synthesize faces that are indistinguishable to the human eyes, which could pose a threat to public security. But latest work has shown that it is possible to identify fakes using powerful CNN networks as classifiers. However, the reliability of these techniques is unknown. Therefore, in this paper we focus on the generation of content-preserving images from fake faces to spoof classifiers. Two GAN-based frameworks are proposed to achieve the goal in the white-box and black-box. For the white-box, a network without up/down sampling is proposed to generate face images to confuse the classifier. In the black-box scenario (where the classifier is unknown), real data is introduced as a guidance for GAN structure to make it adversarial, and a Real Extractor as an auxiliary network to constrain the feature distance between the generated images and the real data to enhance the adversarial capability. Experimental results show that the proposed method effectively reduces the detection accuracy of forensic models with good transferability.

Vulnerability detection and exploitation serves as a milestone for secure development and identifying major threats in software applications. Automated exploit generation helps in easier identification of bugs, the attack vectors and the various possibilities of generation of the exploit payload. Thus, we introduce AngErza which uses dynamic and symbolic execution to identify hot-spots in the code, formulate constraints and generate a payload based on those constraints. Our tool is entirely based on angr which is an open-sourced offensive binary analysis framework. The work around AngErza focuses on exploit and vulnerability detection in CTF-style C binaries compiled on 64-bit Intel architecture for the early-phase of this project.

BYOD or Bring Your Own Device is a set of policies that allow employees of an organization to use their own devices for official work purposes. BYOD is an immensely popular concept in the present day due to the many advantages it provides. However, the implementation of BYOD policies entail diverse problems and as a result, the confidentiality of documents can be breached. Furthermore, employees without security awareness and training are highly vulnerable to endpoint attacks, network attacks, and zero-day attacks that lead to a breach of confidentiality, integrity, and availability (CIA). In this context, this paper proposes a comprehensive solution; ‘BYODENCE’, for the detection and prevention of unauthorized access to organizational documents. BYODENCE is an efficient BYOD solution which can produce competitive results in terms of accuracy and speed.

A service-based system (SBS) dynamically composes third-party services to deliver comprehensive functionality. As adaptive systems, SBSs can substitute equivalent services within the composition if service operations or workflow requirements change. Substituted services must maintain the original SBS quality of service (QoS) constraints. In this paper, we add security as a QoS constraint. Using a model problem of a SBS system created for self-adaptive system technology evaluation, we demonstrate the applicability of security assurance cases and service security profile exchange to build in security awareness for more informed SBS adaptation.

Robustness, both to accident and to malevolent perturbations, is a crucial determinant of the successful deployment of deep convolutional neural network based SAR ATR systems in various security-sensitive applications. This paper performs a detailed adversarial robustness evaluation of deep convolutional neural network based SAR ATR models across two public available SAR target recognition datasets. For each model, seven different adversarial perturbations, ranging from gradient based optimization to self-supervised feature distortion, are generated for each testing image. Besides adversarial average recognition accuracy, feature attribution techniques have also been adopted to analyze the feature diffusion effect of adversarial attacks, which promotes the understanding of vulnerability of deep learning models.

Mathematical morphology has been explored in deep learning architectures, as a substitute to convolution, for problems like pattern recognition and object detection. One major advantage of using morphology in deep learning is the utility of morphological erosion and dilation. Specifically, these operations naturally embody interpretability due to their underlying connections to the analysis of geometric structures. While the use of these operations results in explainable learned filters, morphological deep learning lacks attribution modeling, i.e., a paradigm to specify what areas of the original observed image are important. Furthermore, convolution-based deep learning has achieved attribution modeling through a variety of neural eXplainable Artificial Intelligence (XAI) paradigms (e.g., saliency maps, integrated gradients, guided backpropagation, and gradient class activation mapping). Thus, a problem for morphology-based deep learning is that these XAI methods do not have a morphological interpretation due to the differences in the underlying mathematics. Herein, we extend the neural XAI paradigm of saliency maps to morphological deep learning, and by doing, so provide an example of morphological attribution modeling. Furthermore, our qualitative results highlight some advantages of using morphological attribution modeling.

To break the data barrier of the information island and explore the value of data in the past few years, it has become a trend of uploading data to the cloud by data owners for data sharing. At the same time, they also hope that the uploaded data can still be controlled, which makes access control of cloud data become an intractable problem. As a famous cryptographic technology, ciphertext policy-based attribute encryption (CP-ABE) not only assures data confidentiality but implements fine-grained access control. However, the actual application of CP-ABE has its inherent challenge in attribute revocation. To address this challenge, we proposed an access control solution supporting attribute revocation in cloud computing. Unlike previous attribute revocation schemes, to solve the problem of excessive attribute revocation overhead, we use symmetric encryption technology to encrypt the plaintext data firstly, and then, encrypting the symmetric key by utilizing public-key encryption technology according to the access structure, so that only the key ciphertext is necessary to update when the attributes are revoked, which reduces the spending of ciphertext update to a great degree. The comparative analysis demonstrates that our solution is reasonably efficient and more secure to support attribute revocation and access control after data sharing.