Theoretical and Applied Cybersecurity

Method of Security Improvement for MST3 Cryptosystem Based on Automorphism Group of Ree Function Field

Yevgen Kotukh — 2023-11-06

This article is a part of a research endeavor focused on creating a quantum-resistant cryptosystem for secure encryption and decryption. Our approach employs a challenging word problem while emphasizing cost-effective implementation. Previous research has involved the development of encryption schemes based on high-order groups, offering potential security enhancements. The choice of the non-abelian group is a critical factor in shaping the encryption algorithms, feasibility of implementation, and system parameters. Our central objective is to design a cryptosystem that effectively thwarts quantum cryptanalysis. To achieve this, we employ a logarithmic signature along with a random cover across an entire finite non-abelian group. Our unique contribution lies in optimizing finite group selection, parameters, and circuit solutions for the logarithmic signature to meet specific security and implementation criteria. Within this paper, we introduce an encryption scheme utilizing automorphisms of the Ree functional field and propose a method for enhancing resistance to cryptanalysis through the binding of session keys.

Cryptanalysis of the «Vershyna» digital signature algorithm

Andrii Fesenko — 2023-11-06

The CRYSTALS-Dilithium digital signature algorithm, which was selected as the prototype of the new «Vershyna» digital signature algorithm, is analyzed in this paper. The characteristics of the National Digital Signature Standard Project and the construction of the «Vershyna» algorithm are also presented. During the analysis of the project, the predicted number of iterations that the algorithm must perform to create the correct signature was calculated. In addition, basic theoretical information about the structure of Fiat-Shamir with aborts and its security in quantum and classical models oracle models is also provided. We obtain our own results on the resistance of the «Vershyna» algorithm to the attack without the use of a message in classical and quantum oracle models. The resistance of the «Vershyna» algorithm to a key recovery attack is based on the assumption of the hardness of the MLWE~problem, and the resistance to existential signature forgery is based on the assumption of the hardness of the MSIS~problem. In this work, the expected level of hardness of SIS~and LWE~problems is calculated, to which there are reductions from MSIS~and MLWE~problems.

On Inverse Protocols of Post Quantum Cryptography Based on Pairs of Noncommutative Multivariate Platforms Used in Tandem

Vasyl Ustymenko — 2023-11-06

Non-commutative cryptography studies cryptographic primitives and systems which are based on algebraic structures like groups, semigroups and noncommutative rings. We continue to investigate inverse protocols of Non-commutative cryptography defined in terms of subsemigroups of Affine Cremona Semigroups over finite fields or arithmetic rings Zm and homomorphic images of these semigroups as possible instruments of Post Quantum Cryptography. This approach allows to construct cryptosystem which are not public keys, when protocol finish correspondents have mutually inverse transformations on affine space Kn or variety (K*)n where K is the field or arithmetic ring.

The security of such inverse protocol rests on the complexity of word problem to decompose element of Affine Cremona Semigroup given in its standard form into composition of given generators. We discuss the idea of usage combinations of two cryptosystems with cipherspaces(K*)n and Kn to form a new cryptosystem with the plainspace(K*)n, ciphertextKn and nonbijective highly nonlinear encryption map.

Mathematical Model of the Process of Raising Integers to an Arbitrary Power of a Natural Number in the System of Residual Classes

Alina Yanko — 2023-11-06

It is known that the use of a non-positional number system in residual classes (SRC) in computer systems (CS) can significantly increase the speed of the implementation of integer arithmetic operations. The use of such properties of a non-positional number system in the SRC as independence, equality and low-bitness (low-digit capacity) of the residues that define the non-positional code data structure of the SRC provides high user performance for the implementation in the CS of computational algorithms consisting of a set of arithmetic (modular) operations. The greatest efficiency from the use of the SRC is achieved when the implemented algorithms consist of a set of arithmetic operations such as addition, multiplication and subtraction.

There is a large class of algorithms and tasks (tasks of implementing cryptoalgorithms, optimization tasks, computational tasks of large dimension, etc.), where, in addition to performing integer arithmetic operations of addition, subtraction, multiplication, raising integers modulo and others in a positive numerical range, there is a need to implement the listed above arithmetic and other operations, in the negative numerical range. The need to perform these operations in a negative numerical range significantly reduces the overall efficiency of using the SRC as a number system of the CS. In this aspect, the lack of a mathematical model for the process of raising integers in the SRC in the negative numerical region makes it difficult to develop methods and procedures for raising integers to an arbitrary power of a natural number in the SRC, both in positive and negative numerical ranges.

The purpose of the article is the synthesis of a mathematical model of the process of raising integers to an arbitrary power of a natural number in the SRC, both in positive and negative numerical ranges.

Models of Denial of Service Attacks on Cyber-Physical Systems

Mykola Ovcharuk — 2023-11-06

Mathematical models of denial-of-service attacks are investigated in the paper. Threats of kinetic impact on systems in cyberspace are considered. Targeted computer systems and systems with low and high-security levels were studied. The simulation results demonstrate a successful resolution of the task.

Vulnerability classification using Q-analysis

Viktoriia Igorivna Polutsyhanova — 2023-11-06

Today, vulnerability analysis is of great importance in assessing system security. This approach is especially important in cyber systems. The complex relationship between vulnerabilities is dictated by the threats that potentially arise from their presence. The work provides a methodology and an example of building, analyzing and classifying vulnerabilities depending on the threats that they generate. This approach will allow a better understanding of the connections between vulnerabilities, as well as the degree of impact of each of them.

Detection of Unauthorized Actions in Networks Using Wavelet Analysis

Pavlo Hrynchenko — 2023-11-06

Signal processing techniques are used to analyze and detect network anomalies because of their ability to detect new and unknown intrusions. The paper proposes a method of modeling network signals for the detection of network anomalies, which combines wavelet approximation and the theory of system identification. To characterize the behavior of network traffic, fifteen functions are provided, which are used as input signals within the system. At the same time, it is assumed that security violations within the network can be detected by checking abnormal patterns of system functioning according to audit data.

Despite the fact that machine learning methods have achieved significant results in detecting network anomalies, they still face the difficulty of using the implemented algorithms, in the presence of differences in the behavior of the training data and test data, which in turn leads to inefficient performance of the algorithms. This effect is exacerbated by the limitation of algorithms to detect previously unknown types of attacks due to the large number of false positives.

The paper develops a new method of modeling network signals for detecting anomalies in networks using wavelet analysis. In particular, the general architecture of the approach consists of three components: feature analysis, modeling of normal network traffic based on wavelet approximation and prediction using ARX model, intrusion or non-intrusion decision making

The result is evaluated using the DARPA intrusion detection dataset, which performs a comprehensive analysis of the intrusions in the dataset. Evaluation results show that this approach provides a high level of detection of both instances and types of attacks.

Complexity of The Systems of Linear Restrictions over a Finite Field

Oleh Kurinnyi — 2023-11-06

This paper continues the results obtained in [1]. In the previous paper, we formulated the problem of the unknown vector recovering from linear dependencies with this vector, which act as constraints on it. The next step, after finding out some algebraic and combinatorial properties, is to give basic estimates of complexity for the main problem as well as for related problems. Such related problems can be obtained by fixing some parameters of the main problem or applying constraints on the number of restrictions in the system. Such an analysis makes possible to arrange the problem of recovering an unknown vector based on partial information into the general computational complexity framework in order to approach existing theoretical results to its solution. The obtained theoretical results can be used in algebraic cryptanalysis of stream ciphers and cryptosystems based on linear codes.

The risk management of critical information infrastructure: threats-vulnerabilities-consequences

Vladyslav Kuz — 2023-11-06

Today, interaction between people and objects, including industrial ones, has become an integral part of our everyday life. Access to communications, finance, and all forms of information management and permission to use them can be obtained from almost anywhere using compact devices.

For example, operators can remotely control individual sectors and control operations in several areas at the same time, surgeons can operate on patients thousands of miles away, and car manufacturers can detect when one of their vehicles has been in an accident within a few seconds after the accident.

As a result of the spread of the Internet and wireless data networks, the interconnection of so much data, technology and network equipment and devices has quickly become the basis of modern society. At present, we have become a knowledge-based society that often relies on technology to execute or support almost all tasks and functions of human life. Undoubtedly, this has greatly expanded the range of tasks to be solved, but at the same time, the society became much more vulnerable to threats in information and communication systems.

The vulnerability is explained by the fact that at some point most of the production of different directions and industries is supported by the introduction, storage and search of data/information in a interconnected network of hard disks and data servers, locally or remotely located. And at each of these stages there is an opportunity to steal data, bypass protection, manipulate or replace information. But the risks associated with unintentional accidents caused by human errors, system failures, incompatibility or other unexpected problems, as well as “natural disasters,” must also be taken into account.

Therefore, the security of computer or cyber systems is a matter of national security. Actually, cyber-threats are so great that more and more security experts are pointing out that protection of cyber systems and data is more of a problem than terrorism. Given the scale of the threat (in terms of cyberattacks) and the actual damage it can be argued, certain systems and structures are at risk [1, 2]. It is proved that hackers can break into government and business websites, steal personal data, change the traffic light scheme, accelerate and slow down travel, and much more.

As an example, the implementation of a specially created malware program - Stuxnet. The effects of its use were the self-destruction in 2010 of dozens of centrifuges, which supported Iranʼs nuclear program [3, 4]. Some experts think that Stuxnet was created not by independent attackers and possibly with the support of the government. Thus, as a conclusion, it can be confirmed that hackers operate from anywhere in the world, and the links and boundaries between cyberspace and physical systems are sufficiently leveled. Thus, as a conclusion, it can be confirmed that intruders operate from anywhere in the world, and the links and borders between cyberspace and physical systems are sufficiently leveled.

Society is increasingly faced with the fact that a group or even a person armed with a complex computer virus or knowledge about the vulnerability of software or hardware can cause a lot of physical damage to people’s lives or physical destruction, impose significant social or economic damage, and so on. For example, there are facts published by the Financial times on May 8, 2012 (http://on.ft.com/1wviXHW) that an unknown group for many years is trying to penetrate into the systems of managing the networks of gas pipelines of the USA. At the end of 2014, the National Oceanic and Atmospheric Administration of the United States announced that hackers from China successfully broke and destroyed American satellite networks, causing loss of services related to the prediction of various natural cataclysms, air flight corridors, navigation and other industries within a few days (http://wapo.st/1u7N9dJ).

As a rule, the critical infrastructure includes power and transport main networks, oil and gas pipelines, sea ports, high-speed and governmental communication channels, systems of life support (water and heat supply) of mega-cities, waste management, emergency services and emergency response services, high-tech enterprises and enterprises of military-industrial complex, as well as central authorities.

The government critical information infrastructure is only one of many important systems and networks that create our modern society. Therefore, the state and society are fully dependent on the functioning of different objects and subjects of critical information infrastructure, and the loss of integrity of any of them can lead to various kinds of failures (termination of production and transfer of electricity, temporary and long-term interruptions, improper access to medical care, and much more). Each state is a separate critical information infrastructure, but cooperation between states takes place within the framework of global critical information infrastructure. At the same time, large investments in each sector of critical information infrastructure have led to an increase in economic development rates and improvement in the quality of life.

The Best Scenario of Cyber Attack Selecting on the Information and Communication System Based on the Logical and Probabilistic Method

Lesia Alekseichuk — 2023-11-06

Abstract

The task of analyzing and selecting the best scenario of a cyberattack on information and communication system is considered as a component of the task of analyzing systems security. A method and corresponding algorithm for finding the best scenario of an attack on information and communication system using a logical and probabilistic model is proposed. The model describes the development of adverse events that arise in the information and communication system from the implementation of possible attacks on the security system from cyberspace. Analysis of cyber attack scenarios allows predicting the development of possible adverse cyber security events from the implementation of multiple threats to the system. The developed method and corresponding algorithm for analyzing attack scenarios can be used to analyze the security of information and communication systems, as well as in automation systems for designing information security systems or designing attacks on such systems.

The Development of the Solution Search Method Based on the Improved Bee Colony Algorithm

Andrii Shyshatskyi — 2023-11-06

Active digitization of people's daily life leads to the use of the decision making support systems (DMSS). DMSS is actively used in data processing, forecasting the course of various processes, providing informational support for the decision making process by decision makers. However, a number of problems arise while evaluating monitoring objects, namely: a large number of destabilizing factors affecting the efficiency of the processes of information collection, processing and transmission; high dynamism of changes in the state and composition of heterogeneous monitoring objects during the conduct of hostilities (operations); high dynamism of conducting hostilities (operations); the uncertainty of the initial situation and the noise of the initial data. In this article, a method of finding solutions based on an improved bee colony algorithm was developed.

The efficiency of information processing is achieved by learning the architecture of artificial neural networks; taking into account the type of uncertainty of the information to be evaluated; the use of an improved algorithm of the bee colony, the use of an unordered linguistic scale of measurements with adjustment coefficients for the degree of awareness and the degree of noise of the initial data. An approbation of the use of the proposed method was carried out on the example of assessing the state of the operational grouping of troops (forces). The method is proposed to be used in the development of software for automated systems of control of troops and weapons, namely, in the modernization of existing and development of new automated systems of control of troops and weapons. The evaluation of the effectiveness of the proposed method showed an increase in the efficiency of the evaluation at the level of 21–28% in terms of the efficiency of information processing.

Cybersecurity in AI-Driven Casual Network Formation

Dmytro Lande — 2023-11-06

The paper describes a methodology for forming thematic causal networks using artificial intelligence and automating the processes of their visualization. The presented methodology is considered on the example of ChatGPT, as an artificial intelligence for analyzing the space of texts and building concepts of causal relationships, and their further visualization is demonstrated on the example of Gephi and CSV2Graph programs. The effectiveness of the disaggregated method in relation to traditional methods for solving such problems is shown by integrating the means of intelligent text analytics and graphical network analysis on the example of the problem of data leakage in information systems and a selection of news clippings on the selected topic.

Malware detection system based on static and dynamic analysis and using machine learning

Alan Nafiiev — 2023-11-06

Cyber wars and cyber attacks are an urgent problem in the global digital environment. Based on existing popular detection methods, malware authors are creating ever more advanced and sophisticated malware. Therefore, this study aims to create a malware analysis system that uses both dynamic and static analysis. Our system is based on a machine learning method - support vector machine. The set of data used was collected from various Internet sources. It consists of 257 executable files in .exe format, 178 of which are malicious and 79 are benign. We use 5 different types of data representation: binary information, trace instructions, control flow graph, information obtained from the dynamic operation of the file, and file metadata. Then, using multiple kernel learning, we combine all data views and create one summative machine learning model.