DOCSLIB.ORG

Encrypted Disk Unmount Using Personalized Audio Instruction

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Encrypted Disk Unmount Using Personalized Audio Instruction MASARYK UNIVERSITY FACULTY OF INFORMATICS Encrypted disk unmount using personalized audio instruction BACHELOR'S THESIS Matúš Jarkovič Brno, Fall 2019 Replace this page with a copy of the official signed thesis assignment and a copy of the Statement of an Author. Declaration Hereby I declare that this paper is my original authorial work, which I have worked out on my own. All sources, references, and literature used or excerpted during elaboration of this work are properly cited and listed in complete reference to the due source. Matúš Jarkovič Advisor: RNDr. Dušan Klinec i Acknowledgements Firstly, I would like to express my deepest appreciation to my su• pervisor, RNDr. Dušan Klinec, for all of the suggestions, advice and guidance he provided me throughout the implementation and thesis creation. Secondly, I would like to thank my family that supported me dur• ing the studies. They have provided a very pleasant environment and the thesis would not be possible without them. Lastly, but most importantly I would like to express sincere gratitude to my beloved girlfriend who took care of me at all times. iii Abstract This thesis provides a brief overview of the most popular free open source storage encryption solutions as well as keyword spotting (KWS) systems. It mainly focuses on a basic functionality and highlights main features of these programs. Furthermore, a description of the most used types of storage encryption technologies is included. The goal of the practical part is to extend a disk encryption software VeraCrypt with a KWS system. For this task a tool named Mycroft Precise is used. The main task consists of the integration of these components including a two way communication between them, usage and testing. The purpose of the KWS is to continuously run in the background, process the input speech and notify the main application if user's pre-defined keyword is spotted. If such event occurs, each mounted volume is immediately dismounted. iv Keywords storage encryption technologies, disk encryption, keyword spotting, audio processing, open source, cryptography, VeraCrypt, Mycroft Precise v Contents Introduction 1 1 Storage Encryption 3 1.1 Symmetric Cryptography 4 1.2 Asymmetric Cryptography 5 2 Types of Storage Encryption Technologies 7 2.1 Full/Whole Disk Encryption 7 2.2 Volume/Virtual Disk Encryption 8 2.3 File/Folder Encryption 9 3 The Most Popular Encryption Software 11 3.1 VeraCrypt 11 3.1.1 Volume Encryption 12 3.1.2 System Encryption 12 3.1.3 Plausible Deniability 13 3.1.4 Acceleration and Optimization 14 3.1.5 Encryption and Hashing 15 3.2 Cryptomator 15 3.2.1 Security 16 3.2.2 Encryption and Hashing 17 3.3 7-Zip 17 3.3.1 Encryption 18 3.4 BitLocker 18 3.4.1 Additional Tools 18 3.4.2 Security 19 3.4.3 Encryption 20 3.5 FileVault 20 3.5.1 Security 20 3.5.2 Encryption and Disk Images 21 3.6 Dm-crypt, LUKS and Cryptsetup 21 3.6.1 Security and Encryption 22 3.6.2 Plain Dm-crypt Mode 24 4 Keyword Spotting Software 27 4.1 My croft Precise 29 vii 4.2 PocketSphinx 30 5 Implementation 31 5.1 Keyword Spotting System 31 5.2 Preparation 31 5.3 Integration 33 5.4 Dependencies 34 5.5 Limitations and Future Work 34 5.6 Testing and Recommendations 36 Conclusion 39 Bibliography 41 A Usage Manual 45 B The source code 47 viii List of Figures 1.1 Encryption using Modes of Operation [7] 1.2 Symmetric Cryptography [10] 5 1.3 Asymmetric Cryptography [10] 5 2.1 Boot Sequence for FDE 8 2.2 Full Disk Encryption [13] 8 2.3 Volume Disk Encryption [13] 9 3.1 Hidden Volume [14] 13 3.2 Hidden Operating System [14] 15 3.3 LUKS partition layout [26] 22 3.4 LUKS partition header layout [27] 23 3.5 LUKS key slot layout [27] 24 4.1 HMM topology[35] 29 5.1 Main Window 32 5.2 Dismount Window 35 5.3 Reset Window 35 Introduction The development of information technologies in past few decades has brought a lot of new options which affects everyday life to a high degree, fortunately, mostly in a positive way One of such inventions is the ability to interact with devices using speech. It has been a highly demanded function since it's introduction mainly because of the sim• plicity and comfort it brings for the users. The goal of this thesis is to implement a keyword spotting system into a generally approved disk encryption software VeraCrypt. It is a free open source application which is supported by all main platforms. The program is able to securely store the user data on a media device. Thus, preventing the potential attacker from accessing sensitive infor• mation. The theoretical part provides an overview of the most popular disk encryption solutions and KWS systems freely available. The implemented KWS system, if configured, is continuously lis• tening and processing the audio input from the microphone. When a keyword is detected, VeraCrypt dismounts all of the mounted vol• umes and destroys the key materials used for the data decryption. Therefore, encrypting all of the vulnerable decrypted data. This ex• tension also provides a simple interface for interaction with the KWS system module. The text is divided into five individual chapters. The first chapter provides a brief overview of the available encryption types. The second chaper then covers the technologies which can be used for the storage encryption. Chapter three focuses on the most popular disk encryption solutions while chapter four is a summary of the KWS systems. Finally the last chapter describes the implementation part of the thesis. 1 1 Storage Encryption Storage encryption software is a type of security program that uses cryptography for protecting data stored on media device from unau• thorized access. Software-based encryption is the most commonly used due to its economic feasibility and flexibility. Nevertheless, it has some drawbacks and limitations such as degrading of system perfor• mance, higher power consumption and can be potentially less secure [1]. It hides the true meaning of the data using various encryption algorithms also known as ciphers [2]. These algorithms depend on a key which is used to modify the data. A symmetric key is a sequence of random bits which is used when encrypting plain text or decrypting cipher text. These keys are generated by the encryption program usually by a key derivation function (KDF). It is an essential component of every cryptographic system [3]. An example of a KDF can be the Password-based Key Derivation Function 2 (PBKDF2). It's purpose is to take multiple parameters and derive one or more cryptographically strong keys from this input. User's password in combination with salt, number of iterations and some kind of pseudorandom function (PRF), for example hash-based message authentication code (HMAC) serve as parameters [4]. All these variables are basically applied by the PBKDF2 to the password. The recommended number of iterations are given by standards. These are constantly changing with increasing speeds of central pro• cessing units (CPU) as the iterations increases the processing power needed for brute-force1 (dictionary) attacks. On the other hand, the salt provides better protection against rainbow table2 attacks. Salt is a random data that is added to the password to make the password hash unique. To ensure that the salt is really random and do not de• pend on the internal state of computer, hardware-based noise sources such as microphone input, camera noise or most commonly mouse movements are used. Two major categories of encryption algorithms currently exist, sym• metric and asymmetric [5, 6]. Each of them has unique features that 1. https://en.wikipedia.org/wiki/Bruteforce_attack 2. https://en.wikipedia.org/wiki/Rainbow_table 3 l. STORAGE ENCRYPTION make them adequate for certain tasks. Despite having two completely different types, many times their combination also called hybrid en• cryption is practical. The most common usage is to encrypt the data via symmetric encryption and the symmetric key, used for the data encryption, with asymmetric encryption. 1.1 Symmetric Cryptography Symmetric cryptography [6] or shared secret encryption uses the same key for encrypting and decrypting the data. It is the older technique from the two mentioned. Generally speaking, symmetric key encryp• tion is much more efficient in time and storage requirements than asymmetric. Therefore, it is the one which is used when it comes to encryption of data stored on the media. The symmetric key encryption methods are divided into block ciphers or stream ciphers. Block ciphers, which use constant blocks length, are employed in disk encryption. Encrypting/decrypting a sector is achieved by dividing it into blocks matching the ciphers block size. Applying the cipher to each block separately would not be secure because the same plaintext always produces the same ciphertext. The mode of operation using this method is named electronic codebook (ECB). This mode is very problematic and is not recommended to use. The main problem is that it does not hide data patterns very well which can be seen in the Figure 1.1 [7]. This could lead to potential data leaks. Original image Encrypted using ECB mode Figure 1.1: Encryption using Modes of Operation [7] A possible solution for this problem is using other modes of oper• ation such as cipher-block chaining (CBC), counter (CTR) and many 4 i. STORAGE ENCRYPTION others. The most popular and standardized mode of operation for disk encryption is Xor-encrypt-xor (XEX)-based tweaked-codebook with ciphertext stealing (XTS) [8].
Load more

Recommended publications
  • Self-Encrypting Deception: Weaknesses in the Encryption of Solid State Drives
    Self-encrypting deception: weaknesses in the encryption of solid state drives Carlo Meijer Bernard van Gastel Institute for Computing and Information Sciences School of Computer Science Radboud University Nijmegen Open University of the Netherlands [email protected] and Institute for Computing and Information Sciences Radboud University Nijmegen Bernard.vanGastel@{ou.nl,ru.nl} Abstract—We have analyzed the hardware full-disk encryption full-disk encryption. Full-disk encryption software, especially of several solid state drives (SSDs) by reverse engineering their those integrated in modern operating systems, may decide to firmware. These drives were produced by three manufacturers rely solely on hardware encryption in case it detects support between 2014 and 2018, and are both internal models using the SATA and NVMe interfaces (in a M.2 or 2.5" traditional form by the storage device. In case the decision is made to rely on factor) and external models using the USB interface. hardware encryption, typically software encryption is disabled. In theory, the security guarantees offered by hardware encryp- As a primary example, BitLocker, the full-disk encryption tion are similar to or better than software implementations. In software built into Microsoft Windows, switches off software reality, we found that many models using hardware encryption encryption and completely relies on hardware encryption by have critical security weaknesses due to specification, design, and implementation issues. For many models, these security default if the drive advertises support. weaknesses allow for complete recovery of the data without Contribution. This paper evaluates both internal and external knowledge of any secret (such as the password).
    [Show full text]
  • Analysis of an Encrypted HDD
    Analysis of an encrypted HDD J. Czarny, R. Rigo May 11, 2015 Abstract The idea of this presentation is to debunk the myth that analyzing the security of hardware is difficult. From the perspective of a software reverse engineer we present the process of studying a hardware-encrypted, PIN secured, external hard drive: the Zalman VE-400. While the end result of the analysis and attack is not a full success as it was not possible to recover an encrypted drive, it shows that the drive is nevertheless vulnerable by design. 1 Introduction 1.1 The target Analysing the security of hardware products seems to scare software reversers and hackers. It used to scare us. But, fortunately, today there is no need to know much about electronics, as most products are just System on Chip (SoC), a single integrated circuit with IO and a CPU or microcontroller. All that is needed is a bit of soldering ability, a multimeter, some useful pieces of hardware and a brain. The subject here is not embedded systems in the now common sense of “small hardware running Linux” but smaller systems using one or two chips. Most interesting for software hackers are encrypted HDD/USB keys: their functionnality is conceptually simple and they provide an interesting target. We will focus on the Zalman VE-400 encrypted drive, a consumer enclosure for 2.5" SATA hard drives which supports hardware encryption. It also supports advanced features like mounting ISO files as virtual optical drives. To do so, the user must choose between the ExFAT and NTFS filesystem support, by reflashing the correct firmware.
    [Show full text]
  • Nouveau Mode Opératoire Pour La Cryptographie *
    Nouveau Mode Opératoire pour la Cryptographie * Naima Hadj-Said*, Adda Ali-Pacha, Mohamed Sadek Ali-Pacha – Aek Haouas *Laboratoire SIMPA (Signal-Image-Parole) Université des Sciences et de la Technologie d’Oran USTO , BP 1505 El M’Naouer Oran 31036 Algerie [email protected] Résumé : Un mode opératoire consiste en la description détaillée des actions nécessaires à l'obtention d'un résultat. Il décrit généralement le déroulement détaillé des opérations effectuées sur un poste fixe, mais il peut également décrire l'enchaînement des opérations de poste à poste. Un mode opératoire décrivant les enchaînements opératoires de poste à poste permet de définir : -l'ensemble des postes de travail concernés par la réalisation d'un produit, d'une pièce élémentaire, - les temps de passage prévus (alloués) à chaque poste, -l'ordre logique d'intervention de chaque poste (machine, ou poste manuel), -les conditions d'enchaînement, de déclenchement, des opérations successives, -les moyens de transfert de poste à poste. En cryptographie, un mode d'opération est la manière de traiter les blocs de texte clairs et chiffrés au sein d'un algorithme de chiffrement par bloc ou bien c’est la présentation d’une méthode de chaînage des blocs dans un chiffrement par blocs. Plusieurs modes existent possédant leur propre atout, certains sont plus vulnérables que d'autres et certains modes combinent les concepts d'authentification et sécurité. Dans ce travail on essaie de faire la synthèse des modes opératoires des systèmes cryptographique et de proposer une bonne alternative pour faire le bon choix du vecteur d'initialisation de ces modes, avec la suggestion d’un nouveau mode opératoire qu’on a appelé : mode Autonome Secure blocK (ASK).
    [Show full text]
  • Enclave Security and Address-Based Side Channels
    Graz University of Technology Faculty of Computer Science Institute of Applied Information Processing and Communications IAIK Enclave Security and Address-based Side Channels Assessors: A PhD Thesis Presented to the Prof. Stefan Mangard Faculty of Computer Science in Prof. Thomas Eisenbarth Fulfillment of the Requirements for the PhD Degree by June 2020 Samuel Weiser Samuel Weiser Enclave Security and Address-based Side Channels DOCTORAL THESIS to achieve the university degree of Doctor of Technical Sciences; Dr. techn. submitted to Graz University of Technology Assessors Prof. Stefan Mangard Institute of Applied Information Processing and Communications Graz University of Technology Prof. Thomas Eisenbarth Institute for IT Security Universit¨atzu L¨ubeck Graz, June 2020 SSS AFFIDAVIT I declare that I have authored this thesis independently, that I have not used other than the declared sources/resources, and that I have explicitly indicated all material which has been quoted either literally or by content from the sources used. The text document uploaded to TUGRAZonline is identical to the present doctoral thesis. Date, Signature SSS Prologue Everyone has the right to life, liberty and security of person. Universal Declaration of Human Rights, Article 3 Our life turned digital, and so did we. Not long ago, the globalized commu- nication that we enjoy today on an everyday basis was the privilege of a few. Nowadays, artificial intelligence in the cloud, smartified handhelds, low-power Internet-of-Things gadgets, and self-maneuvering objects in the physical world are promising us unthinkable freedom in shaping our personal lives as well as society as a whole. Sadly, our collective excitement about the \new", the \better", the \more", the \instant", has overruled our sense of security and privacy.
    [Show full text]
  • Format Preserving Encryption
    – Figure 1: Cover picture Format Preserving Encryption Bachelor Thesis Degree programme: Bachelor of Science in Computer Science Author: Matthias Liechti, Rizja Schmid Thesis advisor: Prof. Dr. Reto Koenig Expert: Stefan Berner Date: 12.06.2015 Berner Fachhochschule | Haute école spécialisée bernoise | Bern University of Applied Sciences Management Summary This thesis aims to give a theoretical as well as practical overview of an emerging issue in the field of IT security named Format Preserving Encryption (FPE). Although FPE is not new, it is relatively unknown. It is used in the full-disk encryption and some other areas. Nevertheless, it is to this day even unknown to many cryptographers. Another issue that is on everyone's lips is the Internet of Things (IoT). IoT offers a whole new scope for FPE and could give it possibly a further boost. Format Preserving Encryption is - as the name says - an encryption in which the format of the encrypted data is maintained. When a plaintext is encrypted with FPE, the ciphertext then has the same format again. As illustrated for example on the cover page: If we encrypt the owner and the number of a credit card with AES we get an unrecognizable string. If we use FPE instead, we might get for example Paul Miller and the number 4000 0838 7507 2846. The advantage is that for man and/or machine nothing changes. The encryption is therefore not noticed without analysis of the data. The advantage can also become a disadvantage. An attacker has with the format of the ciphertext already information about the plaintext.
    [Show full text]
  • (12) United States Patent (10) Patent No.: US 9,514,285 B2 Durham Et Al
    USO09514285B2 (12) United States Patent (10) Patent No.: US 9,514,285 B2 Durham et al. (45) Date of Patent: Dec. 6, 2016 (54) CREATING STACK POSITION DEPENDENT (56) References Cited CRYPTOGRAPHC RETURN ADDRESS TO MTGATE RETURN ORIENTED U.S. PATENT DOCUMENTS PROGRAMMING ATTACKS 7.853,803 B2 * 12/2010 Milliken ................. GO6F 21/52 713, 176 (71) Applicant: Intel Corporation, Santa Clara, CA 2014/0173293 A1* 6/2014 Kaplan ................... G06F 21.54 (US) T13, 190 (72) Inventors: David M. Durham, Beaverton, OR OTHER PUBLICATIONS (US); Baiju V. Patel, Portland, OR “Disk encryption theory,” available at http://en.wikipedia.org/wiki/ (US) XEX-TCB-CTS, accessed Dec. 29, 2014, 6 pages. “The Heartbleed bug, available at http://heartbleed.com/, accessed (73) Assignee: Intel Corporation, Santa Clara, CA Dec. 29, 2014, 7 pages. (US) “OpenSSL.” available at http://en.wikipedia.org/wiki/OpenSSL, accessed Dec. 29, 2014, 13 pages. (*) Notice: Subject to any disclaimer, the term of this “Return-oriented programming,' available at http://en.wikipedia. patent is extended or adjusted under 35 org/wiki/Return-oriented programming, accessed Dec. 29, 2014, 4 pageS. U.S.C. 154(b) by 0 days. “Buffer overflow,” available at http://en.wikipedia.org/wiki/Buf (21) Appl. No.: 14/498,521 fer overflow, accessed Dec. 29, 2014, 12 pages. (22) Filed: Sep. 26, 2014 * cited by examiner Primary Examiner — Jacob Lipman (65) Prior Publication Data (74) Attorney, Agent, or Firm — Barnes & Thornburg US 2016/0094.552 A1 Mar. 31, 2016 LLP (51) Int. C. (57) ABSTRACT G6F 2/54 (2013.01) A computing device includes technologies for securing G06F2L/00 (2013.01) return addresses that are used by a processor to control the (52) U.S.
    [Show full text]
  • Secure Content Distribution from Insecure Cloud Computing Systems
    Secure Content Distribution from Insecure Cloud Computing Systems A Thesis submitted to the designated by the Assembly of the Department of Computer Science and Engineering Examination Committee by Evangelos Dimoulis in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN DATA AND COMPUTER SYSTEMS ENGINEERING WITH SPECIALIZATION IN ADVANCED COMPUTER SYSTEMS University of Ioannina School of Engineering Ioannina August 2021 Examining Committee: • Stergios Anastasiadis, Associate Professor, Department of Computer Science and Engineering, University of Ioannina (Advisor) • Evaggelia Pitoura, Professor, Department of Computer Science and Engineer- ing, University of Ioannina • Evangelos Papapetrou, Assistant Professor, Department of Computer Science and Engineering, University of Ioannina ACKNOWLEDGEMENTS First and foremost, I would like to express my sincere gratitude to my research advisor Prof. Stergios Anastasiadis for his invaluable assistance and guidance throughout this thesis. With his deep knowledge on the field of computer systems, he taught methe process of conducting research, how to understand, design and implement systems software. He was always available for long and creative brainstorming sessions, and it was a great privilege to work under his guidance. I would also like to thank my friends who helped relax and clear my mind after many demanding working hours required to complete this research. Especially, Anargyros Katsoulieris with whom we worked together at the Computer Systems Lab, for the many hours of brainstorming sessions in the field of computer systems security, and his funny jokes that helped making time at the office even better. Above all, however, I am grateful to my family for their support, love, care and for encouraging me to pursue and accomplish my goals.
    [Show full text]
  • Android 7 File Based Encryption and the Attacks Against It
    Android 7 File Based Encryption and the Attacks Against It Ronan Loftus Marwin Baumann [email protected] [email protected] Research Project 1 Supervised by: Rick Van Galen Ruben De Vries January 2017 Abstract Android users have been provided with some level of disk encryption since Android 3.0 \Honeycomb". This is marketed as `Full Disk' encryption (FDE). FDE allows users to encrypt their /data partition. The major problem with FDE is that after rebooting, multiple critical functions of the device are unusable without user interaction. File Based encryption (FBE) was introduced to overcome this issue as part of the release of Android 7.0 \Nougat" in August 2016. FBE allows different files to be encrypted with different keys that can be unlocked independently. This fixes the shortcoming of FDE and also allows for more fine grained control of what's encrypted. The security of FDE has been researched quite extensively. Due to its recent release FBE has not been studied. In this paper we elucidate the workings of FBE. We then catalogue some of the known attacks against Android FDE. For each attack we introduce how they function along with the Android specific mechanisms they use. Then we either reason about or practically apply these attacks to the most recent Android version. Over half of the attacks we test are still applicable for Android 7. Finally we provide some recommendations for how these attacks can be rendered obsolete. 1 Contents 1 Introduction 3 1.1 Research question . .3 2 Related Work 4 2.1 Contribution . .4 3 Methodology 5 4 Android Disk Encryption 6 4.1 `Full Disk' .
    [Show full text]
  • Security Analysis and Decryption of Filevault 2
    Chapter 23 SECURITY ANALYSIS AND DECRYPTION OF FILEVAULT 2 Omar Choudary, Felix Grobert and Joachim Metz Abstract This paper describes the first security evaluation of FileVault 2, a vol- ume encryption mechanism that was introduced in Mac OS X 10.7 (Lion). The evaluation results include the identification of the algo- rithms and data structures needed to successfully read an encrypted volume. Based on the analysis, an open-source tool named libfvde was developed to decrypt and mount volumes encrypted with FileVault 2. The tool can be used to perform forensic investigations on FileVault 2 encrypted volumes. Additionally, the evaluation discovered that part of the user data was left unencrypted; this was subsequently fixed in the CVE-2011-3212 operating system update. Keywords: Volume encryption, full disk encryption, FileVault 2 1. Introduction The FileVault 2 volume encryption software was first included in Mac OS X version 10.7 (Lion). While the earlier version of FileVault (intro- duced in Mac OS X 10.3) only encrypts the home folder, FileVault 2 can encrypt the entire volume containing the operating system – referred to as “full disk encryption.” This has two major implications. The first is that there is a new functional layer between the encrypted volume and the original filesystem (typically a version of HFS Plus). This new functional layer is actually a full volume manager, which Apple calls CoreStorage. Although the full volume manager could be used for more than volume encryption (e.g., mirroring, snapshots and online storage migration), we do not know of any other applications. Therefore, in the rest of this paper we use the term CoreStorage to refer to the com- bination of the encrypted volume and the functional layer that links the volume to the HFS Plus filesystem.
    [Show full text]
  • Open-Source-Lösungen Zur Wahrung Der Datensicherheit Und
    Fachhochschule Hannover Fakult¨at IV - Wirtschaft und Informatik Studiengang Angewandte Informatik MASTERARBEIT Open-Source-L¨osungen zur Wahrung der Datensicherheit und glaubhaften Abstreitbarkeit in typischen Notebook-Szenarien Jussi Salzwedel September 2009 Beteiligte Erstprufer¨ Prof. Dr. rer. nat. Josef von Helden Fachhochschule Hannover Ricklinger Stadtweg 120 30459 Hannover E-Mail: [email protected] Telefon: 05 11 / 92 96 - 15 00 Zweitprufer¨ Prof. Dr. rer. nat. Carsten Kleiner Fachhochschule Hannover Ricklinger Stadtweg 120 30459 Hannover E-Mail: [email protected] Telefon: 05 11 / 92 96 - 18 35 Autor Jussi Salzwedel E-Mail: [email protected] 2 Erkl¨arung Hiermit erkl¨are ich, dass ich die eingereichte Masterarbeit selbst¨andig und ohne fremde Hilfe verfasst, andere als die von mir angegebenen Quellen und Hilfsmittel nicht benutzt und die den benutzten Werken w¨ortlich oder inhaltlich entnommenen Stellen als solche kenntlich gemacht habe. Ort, Datum Unterschrift 3 Inhaltsverzeichnis 1 Einfuhrung¨ 14 1.1 Einleitung................................... 14 1.2 Motivation................................... 15 1.3 Typografische Konventionen......................... 18 1.4 Abgrenzung.................................. 18 2 Anwendungsf¨alle 20 2.1 A1: Notebook kommt abhanden....................... 20 2.2 A2: Notebook kommt abhanden und wird nach Verlust gefunden..... 21 2.3 A3: Benutzen des Notebooks, ohne sensitive Daten preiszugeben..... 22 3 Sicherheitsanforderungen 23 3.1 S0: Open-Source............................... 24 3.2 S1: Gew¨ahrleistung der Vertraulichkeit................... 24 3.3 S2: Uberpr¨ ufbarkeit¨ der Integrit¨at...................... 24 3.4 S3: Glaubhafte Abstreitbarkeit........................ 25 4 Theoretische Grundlagen 26 4.1 Verschlusselungsverfahren¨ .......................... 26 4.1.1 Advanced Encryption Standard................... 27 4.1.2 Blowfish................................ 28 4.1.3 Camellia................................ 28 4.1.4 CAST5...............................
    [Show full text]
  • Extracting Ransomware's Keys by Utilizing Memory
    EXTRACTING RANSOMWARE’S KEYS BY UTILIZING MEMORY FORENSICS By Pranshu Bajpai A DISSERTATION Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Computer Science – Doctor of Philosophy 2020 ABSTRACT EXTRACTING RANSOMWARE’S KEYS BY UTILIZING MEMORY FORENSICS By Pranshu Bajpai Ransomware continues to evolve and has established itself as the cyber weapon-of-choice for the financially motivated cybercriminals. The current state of ransomware threats necessi- tates the deployment of defense-in-depth strategies. Particularly, more response and recovery solutions are required to thwart ransomware in the late stages of the attack. To that end, we introduce pickpocket which exploits a side-channel vulnerability in ransomware: in- memory key exposure during encryption. Perpetrators do not control the host performing the encryption and thus this “white box” system affords access to the decryption keys by facilitating an in-memory attack on ransomware. Since it is these keys that are ransomed, the user’s ability to extract the keys cripples the attack. Such key extraction is the only recourse in the frequent scenario where both intrusion prevention and backups have failed. The novelty of pickpocket is the extraction of cryptographic material from system memory during the process of malicious encryption. The primary insight of this work is that con- ventional implementations of cryptographic algorithms deployed by ransomware are highly vulnerable when a hostile entity controls the execution environment. Our work differs from existing solutions in that we provide response and recovery when all existing solutions have failed, that is, we provide the last line of defense.
    [Show full text]
  • Encrypted Disk Unmount Using Personalized Audio Instruction
    Masaryk University Faculty of Informatics Encrypted disk unmount using personalized audio instruction Bachelor’s Thesis Matúš Jarkovič Brno, Fall 2019 Replace this page with a copy of the official signed thesis assignment anda copy of the Statement of an Author. Declaration Hereby I declare that this paper is my original authorial work, which I have worked out on my own. All sources, references, and literature used or excerpted during elaboration of this work are properly cited and listed in complete reference to the due source. Matúš Jarkovič Advisor: RNDr. Dušan Klinec i Acknowledgements Firstly, I would like to express my deepest appreciation to my su- pervisor, RNDr. Dušan Klinec, for all of the suggestions, advice and guidance he provided me throughout the implementation and thesis creation. Secondly, I would like to thank my family that supported me dur- ing the studies. They have provided a very pleasant environment and the thesis would not be possible without them. Lastly, but most importantly I would like to express sincere gratitude to my beloved girlfriend who took care of me at all times. iii Abstract This thesis provides a brief overview of the most popular free open source storage encryption solutions as well as keyword spotting (KWS) systems. It mainly focuses on a basic functionality and highlights main features of these programs. Furthermore, a description of the most used types of storage encryption technologies is included. The goal of the practical part is to extend a disk encryption software VeraCrypt with a KWS system. For this task a tool named Mycroft Precise is used.
    [Show full text]