Proximity Assurances Based on Natural and Artificial Ambient Environments

Relay attacks are passive man-in-the-middle attacks that aim to extend the physical distance of devices involved in a transaction beyond their operating environment. In the field of smart cards, distance bounding protocols have been proposed in order to counter relay attacks. For smartphones, meanwhile, the natural ambient environment surrounding the devices has been proposed as a potential Proximity and Relay-Attack Detection (PRAD) mechanism. These proposals, however, are not compliant with industry-imposed constraints that stipulate maximum transaction completion times, e.g. 500 ms for EMV contactless transactions. We evaluated the effectiveness of 17 ambient sensors that are widely-available in modern smartphones as a PRAD method for time-restricted contactless transactions. In our work, both similarity- and machine learning-based analyses demonstrated limited effectiveness of natural ambient sensing as a PRAD mechanism under the operating requirements for proximity and transaction duration specified by EMV and ITSO. To address this, we propose the generation of an Artificial Ambient Environment (AAE) as a robust alternative for an effective PRAD. The use of infrared light as a potential PRAD mechanism is evaluated, and our results indicate a high success rate while remaining compliant with industry requirements

INFRASTRUCTURE-FREE SECURE PAIRING OF MOBILE DEVICES

Mobile devices have advanced tremendously during the last ten years and have changed our daily life in various ways. Secure pairing of mobile devices has become a significant issue considering the huge quantity of active mobile device connections and mobile traffic. However, current commonly used file sharing mobile applications rely on servers completely that are always targeted by attackers. In this thesis work, an innovative mechanism is proposed to generate symmetric keys on both mobile devices independently from a shared movement in arbitrary pattern, which means no server needs to be involved and no data exchange needed. A secret wireless-communication channel can then be established with a particular network strategy

On the security of mobile sensors

PhD ThesisThe age of sensor technology is upon us. Sensor-rich mobile devices are ubiquitous. Smart-phones, tablets, and wearables are increasingly equipped with sensors such as GPS, accelerometer, Near Field Communication (NFC), and ambient sensors. Data provided by such sensors, combined with the fast-growing computational capabilities on mobile platforms, offer richer and more personalised apps. However, these sensors introduce new security challenges to the users, and make sensor management more complicated. In this PhD thesis, we contribute to the field of mobile sensor security by investigating a wide spectrum of open problems in this field covering attacks and defences, standardisation and industrial approaches, and human dimensions. We study the problems in detail and propose solutions. First, we propose “Tap-Tap and Pay” (TTP), a sensor-based protocol to prevent the Mafia attack in NFC payment. The Mafia attack is a special type of Man-In-The-Middle attack which charges the user for something more expensive than what she intends to pay by relaying transactions to a remote payment terminal. In TTP, a user initiates the payment by physically tapping her mobile phone against the reader. We observe that this tapping causes transient vibrations at both devices which are measurable by the embedded accelerometers. Our observations indicate that these sensor measurements are closely correlated within the same tapping, and different if obtained from different tapping events. By comparing the similarity between the two measurements, the bank can distinguish the Mafia fraud apart from a legitimate NFC transaction. The experimental results and the user feedback suggest the practical feasibility of TTP. As compared with previous sensor-based solutions, ours is the only one that works even when the attacker and the user are in nearby locations or share similar ambient environments. Second, we demonstrate an in-app attack based on a real world problem in contactless payment known as the card collision or card clash. A card collision happens when more than one card (or NFC-enabled device) are presented to the payment terminal’s field, and the terminal does not know which card to choose. By performing experiments, we observe that the implementation of contactless terminals in practice matches neither EMV nor ISO standards (the two primary standards for smart card payment) on card collision. Based on this inconsistency, we propose “NFC Payment Spy”, a malicious app that tracks the user’s contactless payment transactions. This app, running on a smart phone, simulates a card which requests the payment information (amount, time, etc.) from the terminal. When the phone and the card are both presented to a contactless terminal (given that many people use mobile case wallets to travel light and keep wallet essentials close to hand), our app can effectively win the race condition over the card. This attack is the first privacy attack on contactless payments based on the problem of card collision. By showing the feasibility of this attack, we raise awareness of privacy and security issues in contactless payment protocols and implementation, specifically in the presence of new technologies for payment such as mobile platforms. Third, we show that, apart from attacking mobile devices by having access to the sensors through native apps, we can also perform sensor-based attacks via mobile browsers. We examine multiple browsers on Android and iOS platforms and study their policies in granting permissions to JavaScript code with respect to access to motion and orientation sensor data. Based on our observations, we identify multiple vulnerabilities, and propose “TouchSignatures” and “PINLogger.js”, two novel attacks in which malicious JavaScript code listens to such sensor data measurements. We demonstrate that, despite the much lower sampling rate (comparing to a native app), a remote attacker is able to learn sensitive user information such as physical activities, phone call timing, touch actions (tap, scroll, hold, zoom), and PINs based on these sensor data. This is the first report of such a JavaScript-based attack. We disclosed the above vulnerability to the community and major mobile browser vendors classified the problem as high-risk and fixed it accordingly. Finally, we investigate human dimensions in the problem of sensor management. Although different types of attacks via sensors have been known for many years, the problem of data leakage caused by sensors has remained unsolved. While working with W3C and browser vendors to fix the identified problem, we came to appreciate the complexity of this problem in practice and the challenge of balancing security, usability, and functionality. We believe a major reason for this is that users are not fully aware of these sensors and the associated risks to their privacy and security. Therefore, we study user understanding of mobile sensors, specifically their risk perceptions. This is the only research to date that studies risk perceptions for a comprehensive list of mobile sensors (25 in total). We interview multiple participants from a range of backgrounds by providing them with multiple self-declared questionnaires. The results indicate that people in general do not have a good understanding of the complexities of these sensors; hence making security judgements about these sensors is not easy for them. We discuss how this observation, along with other factors, renders many academic and industry solutions ineffective. This makes the security and privacy issues of mobile sensors and other sensorenabled technologies an important topic to be investigated further

Security and Privacy for Ubiquitous Mobile Devices

We live in a world where mobile devices are already ubiquitous. It is estimated that in the United States approximately two thirds of adults own a smartphone, and that for many, these devices are their primary method of accessing the Internet. World wide, it is estimated that in May of 2014 there were 6.9 billion mobile cellular subscriptions, almost as much as the world population. of these 6.9 billion, approximately 1 billion are smart devices, which are concentrated in the developed world. In the developing world, users are moving from feature phones to smart devices as a result of lower prices and marketing efforts. Because smart mobile devices are ubiquitous, security and privacy are primary concerns. Threats such as mobile malware are already substantial, with over 2500 different types identified in 2010 alone. It is likely that, as the smart device market continues to grow, so to will concerns about privacy, security, and malicious software. This is especially true, because these mobile devices are relatively new. Our research focuses on increasing the security and privacy of user data on smart mobile devices. We propose three applications in this domain: (1) a service that provides private, mobile location sharing; (2) a secure, intuitive proximity networking solution; and (3) a potential attack vector in mobile devices, which utilizes novel covert channels. We also propose a first step defense mechanism against these covert channels. Our first project is the design and implementation of a service, which provides users with private and secure location sharing. This is useful for a variety of applications such as online dating, taxi cab services, and social networking. Our service allows users to share their location with one another with trust and location based access controls. We allow users to identify if they are within a certain distance of one another, without either party revealing their location to one another, or any third party. We design this service to be practical and efficient, requiring no changes to the cellular infrastructure and no explicit encryption key management for the users. For our second application, we build a modem, which enables users to share relatively small pieces of information with those that are near by, also known as proximity based networking. Currently there are several mediums which can be used to achieve proximity networking such as NFC, bluetooth, and WiFi direct. Unfortunately, these currently available schemes suffer from a variety of drawbacks including slow adoption by mobile device hardware manufactures, relatively poor usability, and wide range, omni-directional propagation. We propose a new scheme, which utilizes ultrasonic (high frequency) audio on typical smart mobile devices, as a method of communication between proximal devices. Because mobile devices already carry the necessary hardware for ultrasound, adoption is much easier. Additionally, ultrasound has a limited and highly intuitive propagation pattern because it is highly directional, and can be easily controlled using the volume controls on the devices. Our ultrasound modem is fast, achieving several thousand bits per second throughput, non-intrusive because it is inaudible, and secure, requiring attackers with normal hardware to be less than or equal to the distance between the sender and receiver (a few centimeters in our tests). Our third work exposes a novel attack vector utilizing physical media covert channels on smart devices, in conjunction with privilege escalation and confused deputy attacks. This ultimately results in information leakage attacks, which allow the attacker to gain access to sensitive information stored on a user\u27s smart mobile device such as their location, passwords, emails, SMS messages and more. Our attack uses our novel physical media covert channels to launder sensitive information, thereby circumventing state of the art, taint-tracking analysis based defenses and, at the same time, the current, widely deployed permission systems employed by mobile operating systems. We propose and implement a variety of physical media covert channels, which demonstrate different strengths such as high speed, low error rate, and stealth. By proposing several different channels, we make defense of such an attack much more difficult. Despite the challenging situation, in this work we also propose a novel defense technique as a first step towards research on more robust approaches. as a contribution to the field, we present these three systems, which together enrich the smart mobile experience, while providing mobile security and keeping privacy in mind. Our third approach specifically, presents a unique attack, which has not been seen in the wild , in an effort to keep ahead of malicious efforts

Securing the Internet of Things Communication Using Named Data Networking Approaches

The rapid advancement in sensors and their use in devices has led to the drastic increase of Internet-of-Things (IoT) device applications and usage. A fundamental requirement of an IoT-enabled ecosystem is the device’s ability to communicate with other devices, humans etc. IoT devices are usually highly resource constrained and come with varying capabilities and features. Hence, a host-based communication approach defined by the TCP/IP architecture relying on securing the communication channel between the hosts displays drawbacks especially when working in a highly chaotic environment (common with IoT applications). The discrepancies between requirements of the application and the network supporting the communication demands for a fundamental change in securing the communication in IoT applications. This research along with identifying the fundamental security problems in IoT device lifecycle in the context of secure communication also explores the use of a data-centric approach advocated by a modern architecture called Named Data Networking (NDN). The use of NDN modifies the basis of communication and security by defining data-centric security where the data chunks are secured directly and retrieved using specialized requests in a pull-based approach. This work also identifies the advantages of using semantically-rich names as the basis for IoT communication in the current client-driven environment and reinforces it with best-practices from the existing host-based approaches for such networks. We present in this thesis a number of solutions built to automate and securely onboard IoT devices; encryption, decryption and access control solutions based on semantically rich names and attribute-based schemes. We also provide the design details of solutions to sup- port trustworthy and conditionally private communication among highly resource constrained devices through specialized signing techniques and automated certificate generation and distribution with minimal use of the network resources. We also explore the design solutions for rapid trust establishment and vertically securing communication in applications including smart-grid operations and vehicular communication along with automated and lightweight certificate generation and management techniques. Through all these design details and exploration, we identify the applicability of the data-centric security techniques presented by NDN in securing IoT communication and address the shortcoming of the existing approaches in this area

KALwEN: a new practical and interoperable key management scheme for body sensor networks

Key management is the pillar of a security architecture. Body sensor networks (BSNs) pose several challenges–some inherited from wireless sensor networks (WSNs), some unique to themselves–that require a new key management scheme to be tailor-made. The challenge is taken on, and the result is KALwEN, a new parameterized key management scheme that combines the best-suited cryptographic techniques in a seamless framework. KALwEN is user-friendly in the sense that it requires no expert knowledge of a user, and instead only requires a user to follow a simple set of instructions when bootstrapping or extending a network. One of KALwEN's key features is that it allows sensor devices from different manufacturers, which expectedly do not have any pre-shared secret, to establish secure communications with each other. KALwEN is decentralized, such that it does not rely on the availability of a local processing unit (LPU). KALwEN supports secure global broadcast, local broadcast, and local (neighbor-to-neighbor) unicast, while preserving past key secrecy and future key secrecy (FKS). The fact that the cryptographic protocols of KALwEN have been formally verified also makes a convincing case. With both formal verification and experimental evaluation, our results should appeal to theorists and practitioners alike

mHealth Engineering: A Technology Review

In this paper, we review the technological bases of mobile health (mHealth). First, we derive a component-based mHealth architecture prototype from an Institute of Electrical and Electronics Engineers (IEEE)-based multistage research and filter process. Second, we analyze medical databases with regard to these prototypic mhealth system components.. We show the current state of research literature concerning portable devices with standard and additional equipment, data transmission technology, interface, operating systems and software embedment, internal and external memory, and power-supply issues. We also focus on synergy effects by combining different mHealth technologies (e.g., BT-LE combined with RFID link technology). Finally, we also make suggestions for future improvements in mHealth technology (e.g., data-protection issues, energy supply, data processing and storage)

Mobile Authentication with NFC enabled Smartphones

Smartphones are becoming increasingly more deployed and as such new possibilities for utilizing the smartphones many capabilities for public and private use are arising. This project will investigate the possibility of using smartphones as a platform for authentication and access control, using near field communication (NFC). To achieve the necessary security for authentication and access control purposes, cryptographic concepts such as public keys, challenge-response and digital signatures are used. To focus the investigation a case study is performed based on the authentication and access control needs of an educational institutions student ID. To gain a more practical understanding of the challenges mobile authentication encounters, a prototype has successfully been developed on the basis of the investigation. The case study performed in this project argues that NFC as a standalone technology is not yet mature to support the advanced communication required by this case. However, combining NFC with other communication technologies such as Bluetooth has proven to be effective. As a result, a general evaluation has been performed on several aspects of the prototype, such as cost-effectiveness, usability, performance and security to evaluate the viability of mobile authentication