Hybrid Attacks Research Articles

Multiclass Classification-Based Side-Channel Hybrid Attacks on Strong PUFs

Physical unclonable functions (PUFs) are promising solutions for low-cost device authentication; hence, ignoring the security of PUFs is becoming increasingly difficult. Generally, strong PUFs are vulnerable to classical machine learning (ML) attacks; however, classical ML attacks do not perform well on strong PUFs with complex structures. Side-channel analysis (SCA) hybrid attacks provide efficient approaches to modeling XOR APUF. However, owing to the inadequate exploitation of all available data, recent SCA hybrid attacks may fail on novel PUF designs, such as MPUF and iPUF. Thus, herein, we introduce a method that combines challenge-response pairs with side-channel information to construct challenge-synthetic-feature pairs (CSPs) via feature cross, thereby making it possible to model strong PUFs through multiclass classification. We propose multiclass classification-based SCA hybrid attacks to model strong PUFs with complex structures. When provided with CSPs, the proposed hybrid attacks use a feed-forward neural network with a softmax activation function to build combined models of PUFs. The combined models predict class labels for given challenges and then reveal responses through simple mappings from these labels. Experimental results show that the proposed attacks could model 16-XOR APUF, (128,5)-MPUF, (8,8)-iPUF, and (2,16)-iPUF with accuracies exceeding 94%. Compared with state-of-the-art modeling techniques, the proposed attack has advantages in terms of modeling accuracy, time cost, and the size of required training data.

A Local Approach to Distributed $H_{\infty }$-Consensus State Estimation Over Sensor Networks Under Hybrid Attacks: Dynamic Event-Triggered Scheme

This paper deals with the distributed <inline-formula><tex-math notation="LaTeX">$H_{\infty }$</tex-math></inline-formula>-consensus state estimation problem for a class of discrete time-varying systems with integral measurements over sensor networks. The addressed target plant has its output modeled as integral measurement so as to account for the interval time taken for sample collection. The signal transmissions between an individual sensor node and its neighboring nodes are first scheduled by a dynamic event-triggered scheme (ETS) for the purpose of energy saving, and such transmissions are further prone to hybrid cyber-attacks (comprising denial-of-service and deception attacks). A distributed estimator is constructed for each node by using the available information from itself and its neighboring nodes such that the estimation error dynamics achieves the prescribed <inline-formula><tex-math notation="LaTeX">$H_{\infty }$</tex-math></inline-formula>-consensus performance in mean square sense. A local performance analysis method is developed to establish sufficient conditions that ensure the existence of the desired distributed estimators, and the corresponding estimator gains are then obtained by solving certain recursive matrix inequalities. The effectiveness of the proposed distributed estimation algorithm is illustrated through extensive simulation studies, where comparative experiments are conducted on time-triggered scheme, static ETS and dynamic ETS.

Bandwidth Allocation-Based Distributed Event-Triggered LFC for Smart Grids Under Hybrid Attacks

In this study, a bandwidth allocation-based distributed event-triggering load frequency control (LFC) has been developed for smart grids to deal with hybrid cyber-attacks, for example, denial-of-service (DoS) attacks and false data injection (FDI) attacks. Firstly, to prevent hybrid cyber-attacks from causing open-loop unstable operation of the LFC systems, we propose a distributed event-triggering communication (ETC) strategy. To attain the maximum usage of bandwidth, a dynamic bandwidth allocation mechanism is integrated with the ETC approach on the basis of resource availability and error between the current state and equilibrium state. This bandwidth reservation and allocation approach aim at detecting attacks and assigning bandwidth to the different channels of distribution networks. Then, by virtue of the Lyapunov approach, the exponential stability criteria are established. Further, the exclusion of Zeno behavior of the designed systems is proved during the control process. Finally, comprehensive case studies show that the proposed method can improve the utilization rate of the network resource.

Adaptive event-triggered state estimation for complex networks with nonlinearities against hybrid attacks

&lt;abstract&gt;&lt;p&gt;This paper investigates the event-triggered state estimation problem for a class of complex networks (CNs) suffered by hybrid cyber-attacks. It is assumed that a wireless network exists between sensors and remote estimators, and that data packets may be modified or blocked by malicious attackers. Adaptive event-triggered scheme (AETS) is introduced to alleviate the network congestion problem. With the help of two sets of Bernoulli distribution variables (BDVs) and an arbitrary function related to the system state, a mathematical model of the hybrid cyber-attacks is developed to portray randomly occurring denial-of-service (DoS) attacks and deception attacks. CNs, AETS, hybrid cyber-attacks, and state estimators are then incorporated into a unified architecture. The system state is cascaded with state errors as an augmented system. Furthermore, based on Lyapunov stability theory and linear matrix inequalities (LMIs), sufficient conditions to ensure the asymptotic stability of the augmented system are derived, and the corresponding state estimator is designed. Finally, the effectiveness of the theoretical method is demonstrated by numerical examples and simulations.&lt;/p&gt;&lt;/abstract&gt;

Distributed Secure State Estimation of Multi-Sensor Systems Subject to Two-Channel Hybrid Attacks

Distributed Secure State Estimation of Multi-Sensor Systems Subject to Two-Channel Hybrid Attacks

ТРУДОВА МІГРАЦІЯ УКРАЇНЦІВ ДО РЕСПУБЛІКИ ПОЛЬЩА 2014–2022 рр.

The purpose is to analyze the evolution of the migration policy of Ukraine and Poland since the beginning of the Russian-Ukrainian war in 2014 and in the conditions of the aggravation of migration flows after the Russian large-scale invasion in February 2022. Among the methods, a systemic method was used to study the Polish economic thought regarding the profitability and prospects of attracting Ukrainian labor resources, a comparative analysis of the results of Ukrainian labor migration was also conducted, taking into account the requirements of Polish laws. The position of Poland regarding changes in the direction of Ukrainian migration flows has been analyzed. It has been proven that for Ukrainian citizens, the Republic of Poland remains a country where it is possible to implement social and economic expectations. Official Warsaw provides tangible assistance to Ukraine in its confrontation with Russia, providing jobs for migrant workers and social protection for their family members. The deterioration of Ukraine’s security and foreign economic situation is pushing for more active development of the Polish labor market. Currently, the Polish border has become a border against the hybrid expansion of the Russian Federation, so it will be necessary for official Kyiv to ensure the stability and flexibility of its own monetary policy and permit system in order to preserve the possibilities of reproduction of production processes It has been concluded that Polish economists hold a picture that the liberalization of the Polish migration policy towards Ukrainians will contribute to the steady growth of the economy. Recommendations have been made that active steps taken by official Warsaw regarding the growing interest in Ukrainian labor resources would lead to the implementation of vital steps taken by the Polish government to protect against aging tendencies of the Polish nation. It has been highlighted that the implementation of Ukrainian migration policy is dependent on Russian, European and Polish strategies. Under the conditions of the Russian-Ukrainian war, the Polish policy of facilitating the obtaining of legal residence rights and employment of Ukrainian citizens is encouraged by the Ukrainian authorities as an opportunity to receive remittances from abroad, therefore official Kyiv seeks to gain the experience of Poland to attract and use European structural, regional and industry programs and funds. Therefore, Ukraine and Poland, in cooperation with European structures, are able to promote a new quality of security against hybrid attacks of the Russian Federation with the aim of preserving and sustainable development of their own economies and the economies of partners.

Eine handlungsfähigere EU für eine sicherere (östliche) Nachbarschaft – die EU-Belarus-Beziehungen

Since the fraudulent presidential elections in Belarus in August 2020, the country has been in the midpoint of a geopolitical stand-off. Unprecedented violence against peaceful protesters, economic and political sanctions against the regime in Minsk and an orchestrated migration crisis at the European Union’s (EU) external borders have shaped EU-Belarus relations in recent months. In the wake of the crises, the EU stepped up its measures against the Lukashenko regime to be more resilient to hybrid attacks by an authoritarian system and to support the Belarusian democracy movement. The contributions fundament is based on the EU’s Global Strategy, which underpins and provides a framework for the EU-Belarus relations. Furthermore, the article discusses whether the objectives of the strategy have been achieved and if the EU as an international actor can generate security in their Eastern Neighbourhood.

Optimized Intrusion Detection System to Mitigate Hybrid Attacks

Optimized Intrusion Detection System to Mitigate Hybrid Attacks

Robust filtering algorithm against hybrid-attacks and randomly occurring nonlinearities: Application to a quadrotor UAV

This paper addresses the filtering problem for a class of discrete-time cyber-physical system (CPS) in simultaneous presence of physical attack, denial of service attacks (DoS), false data injection (FDI) attacks and randomly occurring nonlinearities (RONs). The malicious attacks can be simultaneously launched at the physical and cyber space to assault/disturb the system's state or block the measurement transmission channels. Firstly, the physical attack is considered as an injected unknown information, which can modify the system's state; then, a unified framework is proposed under which the phenomena of DoS attacks and FDI attacks are depicted by two independent Bernoulli distributed random variables, respectively. Furthermore, the available random probability information of the hybrid attacks and RONs are taken into account in the developed state estimation algorithm. Subsequently, by employing the stochastic analysis and matrix techniques, the exponential boundedness of the state estimation error is discussed from the theoretical aspects. As a typical CPS, a quadrotor unmanned aerial vehicle(UAV) system is provided to demonstrate the effectiveness and practicability of the proposed state estimation method.

Robust H ∞ state estimation for a class of complex networks with dynamic event-triggered scheme against hybrid attacks

We investigate the dynamic event-triggered state estimation for uncertain complex networks with hybrid delays suffering from both deception attacks and denial-of-service attacks. Firstly, the effects of time-varying delays and finite-distributed delays are considered during data transmission between nodes. Secondly, a dynamic event-triggered scheme (ETS) is introduced to reduce the frequency of data transmission between sensors and estimators. Thirdly, by considering the discussed plant, dynamic ETS, state estimator, and hybrid attacks into a unified framework, this framework is transferred into a novel dynamical model. Furthermore, with the help of Lyapunov stability theory and linear matrix inequality techniques, sufficient condition to ensure that the system is exponentially stable and satisfies H ∞ performance constraints is obtained, and the design algorithm for estimator gains is given. Finally, two numerical examples verify the effectiveness of the proposed method.

Countering hybrid threats: does strategic culture matter?

ABSTRACT The COVID-19 pandemic demonstrates once again that hybrid threats are increasingly challenging European countries. Although there is international cooperation on the conceptual level, individual countries are responsible for the actual implementation of counter hybrid measures. This article compares the approaches of Finland, Germany and the Netherlands to counter hybrid threats, while taking into consideration their strategic culture. It shows that the countries differ in their approach to counter hybrid threats in terms of their organisation of security and the scope of measures taken to deter adversaries. These differences are mainly rooted in historical, institutional and political processes. The countries are rather similar in detecting hybrid threats and responding to hybrid attacks, which can be explained by the nature of hybrid threats. Consequently, strategic culture is a context that shapes but not ultimately determines how Finland, Germany and the Netherlands counter hybrid threats. The results of this article suggest that our current understanding of strategic culture is insufficient to describe and explain an actor’s security policy in the contemporary security environment. It is recommended that the concept of strategic culture should be revised and has to be examined more broadly by including national security issues and a broad spectrum of instruments of power.

An event‐triggered approach to security control for networked systems using hybrid attack model

AbstractThis article presents an event‐triggered approach to security control for networked systems by using hybrid attack model. Stochastic deception attacks, replay attacks, and denial of service attacks are assumed to occur in the communication network. The main contribution of the article is that an event‐triggered control strategy is presented to stabilize the networked systems based on the hybrid attacks and the network resource limitations. A novel event‐based model for networked control systems under hybrid attacks is established. Based on the proposed model, sufficient conditions are acquired to guarantee the closed‐loop system stability and the controller design method is developed. Finally, two simulation examples are given to validate the feasibility of the proposed method.

A watermarking scheme for source authentication, ownership identification, tamper detection and restoration for color medical images

This paper proposes a blind watermarking scheme that has ability of confidentiality, source authentication, ownership identification, integrity, tampering detection and restoration of the medical images. It embeds the hospital logo, electronic patient record and perceptual hash value of region of interest in the mid-frequency coefficients of discrete cosine transform of the region of non-interest of medical image. The region of interest of the image is restored against attacks including the desynchronization attacks and impulse noise attack, and the severity of tampering due to any attack is measured by comparing the difference between the original perceptual hash value of the region of interest and the extracted perceptual hash value of region of interest of watermarked image. Restoration is done that tampers the region of interest of the images. Number of medical image watermarking schemes that show resilient to many different types of singular and hybrid attacks is very few. The proposed method has inbuilt restoration schemes against different attacks such as rotation, scaling, translation, shearing, horizontal reflection, vertical reflection and impulse noise attacks. Comparison with the latest and state-of-art medical image watermarking schemes shows that the performance of the proposed method is superior to other methods.

Security analysis on optical image hiding with silhouette removal based on the interference

In this paper, the security of the cryptosystem with three phase-only masks (POMs) based on the interference has been evaluated. The security strength of the classical interference-based cryptosystem with two POMs has been enhanced by employing a random phase distribution to generate three POMs. This random phase distribution is utilized not only to replace the partial part of two POMs which could be used to retrieve information of the plaintexts directly, but also to modulate and generate an additional POMs; thus, the silhouette problem could be eradicated and key space would be enlarged. It is shown that the security strength of the interference-based cryptosystem has been improved; however, the random phase distribution is irrelative to the plaintexts and two POMs are dependent. Based on this finding, hybrid attacks including a known-plaintext attack (KPA) and phase-retrieval technique-based processes with different constraints have been proposed to crack the interference-based cryptosystem with three POMs and to release its silhouette problem. Numerical simulations have been carried out to validate the feasibility and effectiveness of the proposed attacks.

ПСИХОЛОГІЧНІ УМОВИ ФОРМУВАННЯ ПАТРІОТИЗМУ У СТРУКТУРІ ОСОБИСТОСТІ В КОНТЕКСТІ СУЧАСНИХ ГІБРИДНИХ ВІЙН

Introduction. The relevance of the study is due to the presence of a powerful information component of modern hybrid conflicts. The use of manipulative techniques in the information space requires the individual to be in a state of heightened attention and is becoming increasingly important to create new effective techniques to combat harmful influences. In these conditions, the patriotism of citizens is of strategic importance for the future of the country and is its socio-psychological resource, one of the important components of which is the potential ability to resist information aggression, psychological readiness to defend their homeland.That is why the presence of qualitatively new security threats, determined by the influence of information factors on the human psyche, requires the development of effective protection against negative information and psychological influence, determining the level of patriotism, based on special conditions today, is extremely relevant at this stage.Purpose. The purpose of this publication is to identify the psychological conditions for the formation of patriotism in the personality structure in the context of modern hybrid wars and to formulate recommendations for improving the system of patriotism formation.Methods. The study is based on the analysis of recent scientific papers that consider the features of modern hybrid wars and different approaches to the phenomenon of “patriotism”, its description as a system of value orientations. Based on the analysis, the main psychological conditions for the formation of patriotism in the structure of personality are determined.Brief conclusions of the author's survey (questionnaire on the author's questionnaire) to determine the current state of patriotism among students and teachers in 2014 are presented. A comparison of the results of sociological research on the manifestations of patriotism among the citizens of Ukraine, conducted by different organizations in the period from 2016 to 2019.Originality. The problem of studying the patriotism of citizens in a hybrid war becomes relevant because it is directly related to improving the quality of security of the country and the psychological security of citizens, minimizing the negative consequences of hybrid attacks. Citizens' patriotism as a socio-psychological resource provides a potential ability to resist information aggression, creates a psychological readiness of citizens to defend their homeland and act in the name of preserving and developing its well-being. The proposed recommendations for improving the system of patriotism of citizens can be taken into account during the implementation of the requirements of the Decree of the President of Ukraine of May 18, 2019 № 286 “On the Strategy of national-patriotic education”.Conclusion. It is important to continue the detailed study of the information and psychological component of the hybrid war with the broad involvement of scientists, experts and researchers to develop a comprehensive normative document on the formation of patriotism of citizens. Promising directions of further scientific work can be considered the development and generalization of methodological recommendations for the most effective technologies, forms and methods of forming the patriotism of the citizens of Ukraine.

Resilient Distributed Coordination Control of Multiarea Power Systems Under Hybrid Attacks

Resilient distributed coordination control is studied on multiarea power systems with low inertia under hybrid attacks, including denial-of-service (DoS) attack and deception attack. The communication among various areas under the DoS attack is deteriorated to switching residual topologies whose time characteristic is modeled by model-dependent average dwell time (MDADT). Deception attack with malicious strategy targeting at negative feedback control is modeled by a sign function. To obtain resilience performance of the power system under low inertia and hybrid attacks, resilient distributed scheme combining load-frequency control (LFC) with virtual inertia control (VIC) is proposed. Then, resilient frequency control problem of the studied power system is converted to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$H_{\infty }$ </tex-math></inline-formula> control of the switched nonlinear system. By employing the Lyapunov stability theory and switched system method, the resilient conditions are given by the lower bound of the average dwell time of each residual topology and the upper bound of deception attacks. Furthermore, a linear matrix inequality (LMI) technique is used to design the distributed resilient control gains of the LFC-VIC scheme. Finally, a simulation of four-area power systems is carried out to verify the validness of our theory.

WSMN: An optimized multipurpose blind watermarking in Shearlet domain using MLP and NSGA-II

Digital watermarking is a remarkable issue in the field of information security to avoid the misuse of images in multimedia networks. Although access to unauthorized persons can be prevented through cryptography, it cannot be simultaneously used for copyright protection or content authentication with the preservation of image integrity. Hence, this paper presents an optimized multipurpose blind watermarking in the Shearlet domain with the help of smart algorithms, including MLP and NSGA-II. In this method, four copies of the robust copyright logo are embedded in the approximate coefficients of Shearlet by using an effective quantization technique. Furthermore, an embedded random sequence as a semi-fragile authentication mark is effectively extracted from details by the neural network. Due to performing an effective optimization algorithm for selecting optimum embedding thresholds and also distinguishing the texture of blocks, the imperceptibility and robustness have been preserved. The experimental results reveal the superiority of scheme with regard to the quality of watermarked images and robustness against hybrid attacks over other state-of-the-art schemes. The average PSNR and SSIM of the dual watermarked images are 38 dB and 0.95, respectively; Besides, it can effectively extract the copyright logo and locates forgery regions under severe attacks with satisfactory accuracy.

Optimal filter design for cyber‐physical systems under stealthy hybrid attacks

AbstractThis article studies the optimal filtering problem for cyber‐physical systems under stealthy hybrid cyber‐attacks. Due to the stealthiness of cyber‐attacks, the optimal filter (OF) consists of an exponentially increasing number of terms, which makes it computationally infeasible in practice. To address this computational issue, an optimal linear filter (OLF) is developed with its estimation performance fairly close to the optimal one. Furthermore, for a system under the stealthy hybrid cyber‐attacks, it is proved that when the system is stable, the exponentially increasing number of terms remain bounded, making the OF stable; and that the OLF is stable if and only if the system is stable. Finally, numerical examples are employed to illustrate the effectiveness of the proposed two filters.

Vulnerability Assessment of Power Grids Against Cost-Constrained Hybrid Attacks

The frequent occurrences of cascading failures in power grids have been receiving continuous attention in recent years. An urgent task for us is to assess the vulnerability of power grids against various kinds of attacks, which trigger cascading failures. In this brief, we formulate a cost-constrained hybrid attack in power grids, where both nodes and links are targeted with a limited total attack cost. Based on the consequence and cost of removing a component (node or link), we propose an attack centrality metric for components, which can be either local or global depending on the depth of cascading failures. We further propose a greedy hybrid attack and another optimal hybrid attack by applying the attack centrality. Simulation results on IEEE bus test data demonstrate that the optimal attack is more efficient than the greedy one. Furthermore, we find, counterintuitively, that the local centrality based attack algorithms perform better than the global centrality based ones when attack cost is a concern. Our work can help in the robustness optimization of power systems by revealing the worst-case attack vulnerability and most vulnerable components.

Visual attention model based dual watermarking for simultaneous image copyright protection and authentication

In this paper, a visual attention model based dual watermarking scheme has been proposed for simultaneous image copyright protection and authentication. The suggested method simultaneously embeds two watermarks inside the host image. First of all, the robust watermark is embedded in the most visually salient region by Hessenberg factorization technique, which has proven to give better results in terms of imperceptibility and robustness. Subsequently, the second watermark acts as a fragile watermark for the purpose of tamper detection and localization. The fragile watermark is infused inside the image via fragile 8 Bit Plane Slicing, as we require for the watermark to be highly responsive to majority of geometric, and non-geometric impairments. The proposed scheme achieves an average Peak Signal to Noise Ratio and Structural SIMilarity Index of 46.88 dB and 0.9897 respectively. Experimental results depict that the projected scheme is extremely robust against most kinds of geometric, signal-processing, and hybrid attacks with an average Normalized Cross Correlation of 0.9401. Moreover, due to the incorporation of the fragile watermark, it can detect and localize tampering of an image with extreme accuracy.