Future wars will be cyber wars and the attacks will be a sturdy amalgamation of cryptography along with malware to distort information systems and its security. The explosive Internet growth facilitates cyber-attacks. Web threats include risks, that of loss of confidential data and erosion of consumer confidence in e-commerce. The emergence of cyber hack jacking threat in the new form in cyberspace is known as ransomware or crypto virus. The locker bot waits for specific triggering events, to become active. It blocks the task manager, command prompt and other cardinal executable files, a thread checks for their existence every few milliseconds, killing them if present. Imposing serious threats to the digital generation, ransomware pawns the Internet users by hijacking their system and encrypting entire system utility files and folders, and then demanding ransom in exchange for the decryption key it provides for release of the encrypted resources to its original form. We present in this research, the anatomical study of a ransomware family that recently picked up quite a rage and is called CTB locker, and go on to the hard money it makes per user, and its source C&C server, which lies with the Internet's greatest incognito mode-The Dark Net. Cryptolocker Ransomware or the CTB Locker makes a Bitcoin wallet per victim and payment mode is in the form of digital bitcoins which utilizes the anonymity network or Tor gateway. CTB Locker is the deadliest malware the world ever encountered.
Botnet phenomenon in smartphones is evolving with the proliferation in mobile phone technologies after leaving imperative impact on personal computers. It refers to the network of computers, laptops, mobile devices or tablets which is remotely controlled by the cybercriminals to initiate various distributed coordinated attacks including spam emails, ad-click fraud, Bitcoin mining, Distributed Denial of Service (DDoS), disseminating other malwares and much more. Likewise traditional PC based botnet, Mobile botnets have the same operational impact except the target audience is particular to smartphone users. Therefore, it is import to uncover this security issue prior to its widespread adaptation. We propose SMARTbot, a novel dynamic analysis framework augmented with machine learning techniques to automatically detect botnet binaries from malicious corpus. SMARTbot is a component based off-device behavioral analysis framework which can generate mobile botnet learning model by inducing Artificial Neural Networks' back-propagation method. Moreover, this framework can detect mobile botnet binaries with remarkable accuracy even in case of obfuscated program code. The results conclude that, a classifier model based on simple logistic regression outperform other machine learning classifier for botnet apps' detection, i.e 99.49% accuracy is achieved. Further, from manual inspection of botnet dataset we have extracted interesting trends in those applications. As an outcome of this research, a mobile botnet dataset is devised which will become the benchmark for future studies.
I present the design and implementation of a novel anti-malware environment called BitAV. BitAV allows for the decentralization of the update and maintenance mechanisms of the software, traditionally performed by a central host, and uses a staggered scanning mechanism in order to improve performance. The peer-to-peer network maintenance mechanism lowered the average update propagation speed by 500% and is far less susceptible to targeted denial-of-service attacks. The feedforward scanning mechanism significantly improved end-to-end performance of the malware matching system, to a degree of an average 14x increase, by decomposing the file matching process into efficient queries that operate in verifiably constant time.
Botnets, in other means zombie computers that await for instructions to execute, are the greatest threat in the internet today. They are one of the leading sources of online crime. Criminals are able to take advantage of using botnets and threaten online businesses, organizations or any entity in the internet. Criminals design and implement botnets in a complex way in order to hide their identities. Most notably the fact that criminals build command-and-control (C&C) infrastructures to manage their botnets. A botnet command-and-control mechanism (C&C) can be designed in various ways. The key principle behind designing a C&C mechanism is anonymity. Hence, criminals can propagate their instructions to botnets without revealing their identities. Since every new C&C mechanism increases the bar of anonymity, it is getting harder to trace and analyze botnets. In this thesis, we designed and implemented a C&C mechanism, btc-botnet, that runs over Bitcoin network. Btcbotnet has significant features over existing C&C mechanisms such as anonymity and resistance by its nature. We built a library that allows to use Bitcoin network as an underlying infrastructure for C&C mechanism. We evaluate our work and show that its feasibility in terms of metrics such as response time, confirmation time and fees.
Thanks to their anonymity (pseudonymity) and elimination of trusted intermediaries, cryptocurrencies such as Bitcoin have created or stimulated growth in many businesses and communities. Unfortunately, some of these are criminal, e.g., money laundering, illicit marketplaces, and ransomware. Next-generation cryptocurrencies such as Ethereum will include rich scripting languages in support of smart contracts, programs that autonomously intermediate transactions. In this paper, we explore the risk of smart contracts fueling new criminal ecosystems. Specifically, we show how what we call criminal smart contracts (CSCs) can facilitate leakage of confidential information, theft of cryptographic keys, and various realworld crimes (murder, arson, terrorism). We show that CSCs for leakage of secrets (a la Wikileaks) are efficiently realizable in existing scripting languages such as that in Ethereum. We show that CSCs for theft of cryptographic keys can be achieved using primitives, such as Succinct Non-interactive ARguments of Knowledge (SNARKs), that are already expressible in these languages and for which efficient supporting language extensions are anticipated. We show similarly that authenticated data feeds, an emerging feature of smart contract systems, can facilitate CSCs for realworld crimes (e.g., property crimes). Our results highlight the urgency of creating policy and technical safeguards against CSCs in order to realize the promise of smart contracts for beneficial goals.
Cryptocurrencies record transactions in a decentralized data structure called a blockchain. Two of the most popular cryptocurrencies, Bitcoin and Ethereum, support the feature to encode rules or scripts for processing transactions. This feature has evolved to give practical shape to the ideas of smart contracts, or full-fledged programs that are run on blockchains. Recently, Ethereum's smart contract system has seen steady adoption, supporting tens of thousands of contracts, holding millions dollars worth of virtual coins. In this paper, we investigate the security of running smart contracts based on Ethereum in an open distributed network like those of cryptocurrencies. We introduce several new security problems in which an adversary can manipulate smart contract execution to gain profit. These bugs suggest subtle gaps in the understanding of the distributed semantics of the underlying platform. As a refinement, we propose ways to enhance the operational semantics of Ethereum to make contracts less vulnerable. For developers writing contracts for the existing Ethereum system, we build a symbolic execution tool called Oyente to find potential security bugs. Among 19, 336 existing Ethereum contracts, Oyente flags 8, 833 of them as vulnerable, including the TheDAO bug which led to a 60 million US dollar loss in June 2016. We also discuss the severity of other attacks for several case studies which have source code available and confirm the attacks (which target only our accounts) in the main Ethereum network.
We live in an era where Internet is one of the daily needs of human life. People use Internet banking instead of going to banks, they use email rather than postal mail.This leads to a robust digital way of living, but this also means people are trusting middle companies and third parties for their online services. The need of having a digital form of money that is not being controlled by one entity is plain to see. \nBitcoin is the first and the most popular decentralized virtual currency. It is based on cryptographic functions to remove the need of a central bank and regulates the generation of new units. \nIn this thesis, we would like to look at available tools to facilitate users in holding and using Bitcoin by a perspective on usability and security, and then evaluate the possibilities for a small business to accept Bitcoin payments. Our focus is on the usability of these tools and developing a useful framework for comparing and eval- uating future tools. While many security tools have been studied from a usability perspective, our work is the first to look at Bitcoin.
We present a new, decentralized, efficient, and secure digital cryptocurrency, in which the ordinary users themselves keep turns to ensure that the systems works well. ∗sergeyg@mit.edu †silvio@csail.mit.edu
This paper focuses on the evolution of cryptocurrencies. It traces the history of early cryptography, the ‘cypherpunk’ movement, and how the work of some cyber libertarians and cryptographers enabled the emergence of popular cryptocurrencies. The paper then focuses on Bitcoin. It delves into the technology behind the Bitcoin architecture and shows how exactly this technology works. The paper then does an analysis of security and regulatory considerations that affect the growth of Bitcoin-based businesses. The paper concludes with some suggestions for future work in the area.
Shayan Eskandari, David Barrera, Elizabeth Stobert, Jeremy Clark
Bitcoin users are directly or indirectly forced to deal with public key cryptography, which has a number of security and usability challenges that differ from the password-based authentication underlying most online banking services. Users must ensure that keys are simultaneously accessible, resistant to digital theft and resilient to loss. In this paper, we contribute an evaluation framework for comparing Bitcoin key management approaches, and conduct a broad usability evaluation of six representative Bitcoin clients. We find that Bitcoin shares many of the fundamental challenges of key management known from other domains, but that Bitcoin may present a unique opportunity to rethink key management for end users.
Open access
3 source records
User Authentication and Security Systems
Advanced Steganography and Watermarking Techniques
Sławomir Grzonkowski, Alejandro Mosquera, Lamine M. Aouad, Dylan Morss
The mobile threat landscape has undergone rapid growth as smartphones have increased in popularity. The first generation of mobile threats saw attackers relying on various scams delivered through SMS. As the technology progressed and Web browsers, e-mail clients, and custom applications became standard on smartphones, attackers started exploiting new possibilities beyond traditional e-mail spam and phishing attacks. The landscape continues to evolve with mobile bitcoin miners, botnets, and ransomware.
Gheith A. Abandah, Khalid A. Darabkh, Tawfiq Ammari, Omar Qunsul
Electronic voting provides accuracy and efficiency to the electoral processes. World democracies would benefit from a secure e-voting system not only to improve voter participation and trust but also to prevent electoral fraud. However, current e-voting systems are complex and have security weaknesses. In this paper, we describe a secure e-voting system for national and local elections (S-Vote). This system satisfies the important requirements of an e-voting system through state-of-the-art technologies and secure processes. S-Vote relies on homomorphic cryptography, zero-knowledge proofs, biometrics, smartcards, open-source software, and secure computers for securely and efficiently implementing the system processes over the various stages of the electoral process, without relying on online network connections. We outline the main conclusions of the pilot implementations of S-Vote that tested the main technologies and processes used. We also explain how the used technologies and processes achieve the system requirement. In conclusion, we recommend adopting S-Vote for its security, flexibility, economic, and scalability features.
This project attempts to implement an open source FPGA based Bitcoin miner on an Altera DE2-115 development board. Bitcoin is an experimental peer-to-peer digital currency based on public key cryptography. The advantages of Bitcoins are that they can be transferred between any two people anywhere in the world, and they do not have the same fees and lack of control associated with traditional methods of currency transfers. The first part of this project focuses on detailing how the Bitcoin network and open source miner work. The second part of the project attempts to improve the performance of the open source miner, but a lack of resources on the Cyclone IV EP4CE115F29C7 ultimately prevented implementing a dual pipelined design.
This thesis illustrates forensic research work on Bitcoin, an innovative Internet based global transaction system that attracts ascending popularity during the recent few years. As an open, public and scalable distributed payment system, Bitcoin brings forward significant economic and technological impact to our world. Meanwhile, a new notion of virtual currency, "Bitcoin" comes into existence such that Bitcoin currency can be "mined" from all over world complying with specific algorithms. Mined bit "coins" has practical monetary values that turn the Bitcoin system into a digital currency circulation system. Due to Bitcoin's decentralized semantics, Bitcoin transaction and currency are not subject to control and censorship from any single authority. Therefore, Bitcoin brings out various security concerns about its application as a long-term reliable system.\nThe research in the thesis focuses on forensic study on Bitcoin. It covers experimental study on the Bitcoin network as a peer-to-peer system and a graph-based forensic approach against Bitcoin's transaction data. Major contributions include network data evaluation and transaction history analysis. In case of forensic investigation is needed against criminal incidents such as fraud, false transactions and money theft, which are commonly seen in commonly used digital payment systems, the research provides a guidance of efficient information collection and framework of evidence data processing and extraction
Gianluca Dini, Fabio Martinelli, Andrea Saracino, Daniele Sgandurra
We propose PICARD (ProbabIlistic Contract on Android), a framework to generate probabilistic contracts to detect repackaged applications for Android smart phones. A contract describes the sequences of actions that an application is allowed to perform at run-time, i.e. its legal behavior. In PICARD, contracts are generated from the set of traces that represent the usage profile of the application. Both the contract and the application's run-time behavior are represented through clustered probabilistic automata. At run-time, the PICARD monitoring system verifies the compliance of the application trace with the contract. This approach is useful in detecting repackaged applications, whose behavior is strongly similar to the original application but it differs only from small paths in the traces. In this paper, we discuss the framework of PICARD for describing and generating contracts through probabilistic automata and introduce the notion of Action Node, a cluster of related system calls, used to represent high level operations. Then, we present a first set of preliminary experiments on repackaged applications, to evaluate the viability of the proposed approach.
Contracts enable mutually suspicious parties to cooperate safely through the exchange of rights. Smart contracts are programs whose behavior enforces the terms of the contract. This paper shows how such contracts can be specified elegantly and executed safely, given an appropriate distributed, secure, persistent, and ubiquitous computational fabric. JavaScript provides the ubiquity but must be significantly extended to deal with the other aspects. The first part of this paper is a progress report on our efforts to turn JavaScript into this fabric. To demonstrate the suitability of this design, we describe an escrow exchange contract implemented in 42 lines of JavaScript code.
Malware and botnets are one of the most serious threats to today's Internet security. In this paper, we characterise the so-called "Miner Botnet". It received major media attention after massive distributed denial of service attacks against a wide range of German and Russian websites, mainly during August and September 2011. We use our insights on this botnet to outline current botnet-related money-making concepts and to show that multiple activities of this botnet are actually centred on the virtual anonymised currency Bitcoin, thus justifying the name. Furthermore, we provide a binary-level analysis of the malware's design and components to illustrate the modularity of the previously mentioned concepts. We give an overview of the structure of the command-and-control protocol as well as of the botnet's architecture. Both centralised as well as distributed infrastructure aspects realised through peer-to-peer are present to run the botnet, the latter for increasing its resiliency. Finally, we provide the results of our ongoing tracking efforts that started in September 2011, focusing on the development of the botnet's size and geographic distribution. In addition we point out the challenge that is generally connected with size measurements of botnets due to the reachability of individual nodes and the persistence of IP addresses over time.
CertiCrypt is a framework that enables the machine-checked construction and verification of cryptographic proofs in the Coq proof assistant. CertiCrypt instruments the code-based game-based approach to cryptographic proofs, and builds upon many areas, including probability and complexity theory, algebra, semantics of programming languages, and program optimizations. In this thesis, we illustrate the application of CertiCrypt on two examples: the Hashed ElGamal encryption scheme and zero-knowledge protocols. Like previous case studies in CertiCrypt, these examples demonstrate the feasibility of formalizing complex cryptographic proofs. However, using CertiCrypt requires a high level of expertise in Coq, and is time consuming. In order to ease the adoption of formal proofs by the cryptographic community, we develop a semi-automated tool, called EasyCrypt, for elaborating security proofs of cryptographic systems from proof sketches. Proof sketches are checked automatically using SMT solvers and automated theorem provers, and then compiled into verifiable proofs in the CertiCrypt framework. We illustrate the application of EasyCrypt with two examples: the Hashed ElGamal encryption system, and the Cramer-Shoup encryption system. Finally, we extend the language of CertiCrypt with a formalization of polytime functions.