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Methods for Realtime Voice Deepfakes Creation
Alakaev, Kambulat ; Pleško, Filip (oponent) ; Malinka, Kamil (vedoucí práce)
This thesis explores the possibility of achieving real-time voice deepfake generation using open-source tools. Through experiments, it was discovered that the generation rate of voice deepfakes is affected by the computing power of the devices running the speech creation tools. A deep learning model was identified to be capable of generating speech in near real time. However, limitations in the tool containing this model prevented continuous input data for real-time generation. To address this, a program was developed to overcome these limitations. The quality of the generated deepfakes was evaluated using both voice deepfake detection models and human online surveys. The results revealed that while the model could deceive detection models, it was not successful in fooling humans. This research highlights the accessibility of open-source voice synthesis tools and the potential for their misuse by individuals for fraudulent purposes.
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Evaluation of Sources of Human Speech for Deepfake Creation
Frič, Michal ; Malinka, Kamil (oponent) ; Firc, Anton (vedoucí práce)
Voice deepfakes, powered by rapid advancements in artificial intelligence and machine learning, represent a dual-edge technology with significant benefits and risks. These synthetic voice outputs are increasingly realistic due to the easy access to vast amounts of digital speech data from various sources. This thesis analyses these sources’ suitability for creating convincing deepfakes. We identified and evaluated numerous speech sources and developed methodologies for assessing their quality, accessibility, diversity, and update frequency. The evaluation extended to analyzing the impact of source characteristics on deepfake quality and the effectiveness of detection by software and human evaluators. Findings indicate that all identified sources can provide sufficiently high-quality recordings to create high-quality deepfakes, often indistinguishable. Additionally, they highlight each source’s particular strengths and weaknesses (measured properties) grade. An anomaly in detection software was discovered, allowing deepfakes to be modified to evade detection. Furthermore, less than 10 seconds of human speech could suffice to create a high-quality deepfake, directly correlating the length and quality of input recordings to the fidelity of the output. The thesis concludes with a discussion of the risks associated with these sources and proposes measures for prevention and mitigation.
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Secure Coding Guidelines for Java
Jalakšová, Michaela ; Malinka, Kamil (oponent) ; Tamaškovič, Marek (vedoucí práce)
Java is a popular programming language that is widely used in a variety of applications. However, Java is not an exception when it comes to being vulnerable to attacks that exploit security vulnerabilities in code. The goal of this thesis is to increase awareness of coding vulnerabilities in Java and to develop an educational tool that will help programmers learn how to write more secure code. The aim of this tool is to provide Java programmers with information about secure coding practices and an environment where they can learn the basics of secure programming. It will also provide a solution to some more common vulnerabilities in Java.
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Communication System for the Volunteer Fire Department
Čajka, Peter ; Firc, Anton (oponent) ; Malinka, Kamil (vedoucí práce)
The process of gathering volunteer firefighters in case of an emergency is often not optimal. In critical situations, every second counts. The goal of this thesis is to create a mobile application that simplifies the process of informing volunteer firefighters about an emergency event. The resulting product will be a mobile application for the Android operating system, capable of rapidly sending SMS messages to all members of the volunteer fire department in case of an emergency and subsequently receiving their responses.
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Security Analysis and Hardening of Multiplatform Application
Hráček, Ondřej ; Reš, Jakub (oponent) ; Malinka, Kamil (vedoucí práce)
My aim was to make my application more secure. The application consists of multiple parts which had to be analysed, updated and tested for further vulnerabilities. I used automated tools to analyze the security concerns of the application. To mitigate all the major security risks, I followed an online guide published by OWASP and hardened the security of two main parts of the application. Finally, I have analysed the security of the application once again using automated tools and penetration testing. As a result, I found out that the major vulnerabilities have been fixed and the most common attacks have been made impossible. The contribution of this thesis is showing how important security concerns and planning are in the whole development cycle of any application and how vulnerable applications can be without secure development practices in mind. However, fixing these mistakes and security hardening is possible and can greatly improve the security of any application.
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Vulnerability Assessment of Container Images
Findra, Michal ; Malinka, Kamil (oponent) ; Pavela, Jiří (vedoucí práce)
The work focuses on the problem of automated security analysis of container images in a distributed environment. It describes present vulnerabilities in these environments and tools that deal with the analysis of container images that serve as a template for deploying a specific container. The process involves acquiring an environment description and subsequently processing it into a format meaningful for Vulntron tool developed as part of this thesis. Vulntron automates this process, performs a security analysis of individual components of the container image, and generates a report in a visually and technically processable format. The thesis also includes practical integration in form of Vulntron deployment into various types of development processes within the Red Hat company.
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Performance Comparison of Libraries for Homomorphic Cryptography
Babjak, Pavol ; Perešíni, Martin (oponent) ; Malinka, Kamil (vedoucí práce)
Cryptography is an integral part of computer security. When using common cryptography methods and operations on them, individual data are not protected against unauthorized access or theft by third parties in any way. Homomorphic cryptography solves the given problem exactly, i.e., it can work with data containing unknown content and simultaneously perform operations on them. The goal of this thesis is to find simple use-case suitable for practical application of homomorphic encryption technology, implement it via frameworks using this technology and measure their performance and other important aspects to choose the most favorable framework and encryption scheme for that practical application.
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Use of Diffusion Models in Deepfakes
Trúchly, Dominik ; Malinka, Kamil (oponent) ; Lapšanský, Tomáš (vedoucí práce)
A deepfake is a type of synthetic media created through sophisticated machine learning algorithms, particularly deep neural networks. As an example Generative adversarial neural networks (GANs), that are capable of generating images that are almost impossible for ordinary individuals to differentiate from genuine reality. Consequently, deepfake detection algorithms have been developed to address this growing concern. Leveraging advanced machine learning techniques, these algorithms analyze various features within images and videos to identify inconsistencies or anomalies indicative of manipulation. This thesis investigates the application of diffusion models, commonly utilized in digital image processing to enhance image quality by reducing noise and blurring, in bolstering the realism of deepfakes. By using these models, we test their effect on detecting deepfakes images using deepfake detectors.
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Útoky na Centos/RedHat 7
Krychtálek, Petr ; Malinka, Kamil (oponent) ; Snášel, Daniel (vedoucí práce)
Cílem této práce je analýza pěti vybraných exploitů zaměřujících se na operační systém CentOS 7. V první části jsou představeny teoretické koncepty potřebné pro pochopení funkce exploitů. Mezi tyto koncepty patří operační systém, jádro operačního systému, proces, vlákno a virtuální paměť. Druhá část je už konkrétně zaměřena na operační systém Linux a jeho architekturu. Třetí část se zabývá kybernetickou bezpečností, přičemž jsou uvedeny nejčastější typy útoků, nejčastější typy zranitelností a taky nástroje využívané v oblasti kybernetické bezpečnosti. Čtvrtá část se zaměřuje na bezpečnost operačního systému Linux a jeho nejčastějším zranitelnostem. Poslední část této práce je věnována podrobné analýze exploitů a hledáním exploitů.
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Reversibility of Voice Change Methods
Lička, Zbyněk ; Firc, Anton (oponent) ; Malinka, Kamil (vedoucí práce)
State-of-the-art voice-changing methods allow inexperienced users to create convincing voice recordings of famous individuals with just a few seconds of recorded speech. There are two major approaches to voice generation: voice conversion and text-to-speech. Voice conversion methods require the user to input source speech to be converted to the target voice. A trend with voice conversion methods, especially those requiring only mere seconds of reference speech, has been restricting the amount of information about the original speaker in the converted speech. This work focuses on studying the amount of information extractable about the original speaker from artificial speech and potentially reconstructing the original speech. The results of this work shed light on an unstudied property of voice-changing methods.
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