User Authentication and Supervision in Networked Systems

This thesis considers the problem of user authentication and supervision in networked systems. The issue of user authentication is one of on-going concern in modem IT systems with the increased use of computer systems to store and provide access to sensitive information resources. While the traditional username/password login combination can be used to protect access to resources (when used appropriately), users often compromise the security that these methods can provide. While alternative (and often more secure) systems are available, these alternatives usually require expensive hardware to be purchased and integrated into IT systems. Even if alternatives are available (and financially viable), they frequently require users to authenticate in an intrusive manner (e.g. forcing a user to use a biometric technique relying on fingerprint recognition). Assuming an acceptable form of authentication is available, this still does not address the problem of on-going confidence in the users’ identity - i.e. once the user has logged in at the beginning of a session, there is usually no further confirmation of the users' identity until they logout or lock the session in which they are operating. Hence there is a significant requirement to not only improve login authentication but to also introduce the concept of continuous user supervision. Before attempting to implement a solution to the problems outlined above, a range of currently available user authentication methods are identified and evaluated. This is followed by a survey conducted to evaluate user attitudes and opinions relating to login and continuous authentication. The results reinforce perceptions regarding the weaknesses of the traditional username/password combination, and suggest that alternative techniques can be acceptable. This provides justification for the work described in the latter part o f the thesis. A number of small-scale trials are conducted to investigate alternative authentication techniques, using ImagePIN's and associative/cognitive questions. While these techniques are of an intrusive nature, they offer potential improvements as either initial login authentication methods or, as a challenge during a session to confirm the identity of the logged-in user. A potential solution to the problem of continuous user authentication is presented through the design and implementation o f a system to monitor user activity throughout a logged-in session. The effectiveness of this system is evaluated through a series of trials investigating the use of keystroke analysis using digraph, trigraph and keyword-based metrics (with the latter two methods representing novel approaches to the analysis of keystroke data). The initial trials demonstrate the viability of these techniques, whereas later trials are used to demonstrate the potential for a composite approach. The final trial described in this thesis was conducted over a three-month period with 35 trial participants and resulted in over five million samples. Due to the scope, duration, and the volume of data collected, this trial provides a significant contribution to the domain, with the use of a composite analysis method representing entirely new work. The results of these trials show that the technique of keystroke analysis is one that can be effective for the majority of users. Finally, a prototype composite authentication and response system is presented, which demonstrates how transparent, non-intrusive, continuous user authentication can be achieved

Oxalis: A Distributed, Extensible Ophthalmic Image Annotation System

Currently, ophthalmic photographers and clinicians write reports detailing the location and types of disease visible in a patient's photograph. When colleagues wish to review the patient's case file, they must match the report with the image. This is both inefficient and inaccurate. As a solution to these problems, we present Oxalis, a distributed, extensible image annotation architecture, implemented in the Java programming language. Oxalis enables a user to: 1) display a digital image, 2), annotate the image with diagnoses and pathologies using a freeform drawing tool, 3) group images for comparison, and 4) assign images and groups to schematic templates for clarity. Images and annotations, as well as other records used by the system, are stored in a central database where they can be accessed by multiple users simultaneously, regardless of physical locality. The design of Oxalis enables developers to modify existing system components or add new ones, such as display capabilities for a new image format, without editing or recompiling the entire system. System components can elect to be notified when data records are created, modified, or removed, and can access the most current system data at any point. While Oxalis was designed for ophthalmic images, it represents a generic architecture for image annotation applications

Identifying and combating cyber-threats in the field of online banking

This thesis has been carried out in the industrial environment external to the University, as an industrial PhD. The results of this PhD have been tested, validated, and implemented in the production environment of Caixabank and have been used as models for others who have followed the same ideas. The most burning threats against banks throughout the Internet environment are based on software tools developed by criminal groups, applications running on web environment either on the computer of the victim (Malware) or on their mobile device itself through downloading rogue applications (fake app's with Malware APP). Method of the thesis has been used is an approximation of qualitative exploratory research on the problem, the answer to this problem and the use of preventive methods to this problem like used authentication systems. This method is based on samples, events, surveys, laboratory tests, experiments, proof of concept; ultimately actual data that has been able to deduce the thesis proposal, using both laboratory research and grounded theory methods of data pilot experiments conducted in real environments. I've been researching the various aspects related to e-crime following a line of research focusing on intrinsically related topics: - The methods, means and systems of attack: Malware, Malware families of banker Trojans, Malware cases of use, Zeus as case of use. - The fixed platforms, mobile applications and as a means for malware attacks. - forensic methods to analyze the malware and infrastructure attacks. - Continuous improvement of methods of authentication of customers and users as a first line of defense anti- malware. - Using biometrics as innovative factor authentication.The line investigating Malware and attack systems intrinsically is closed related to authentication methods and systems to infect customer (executables, APP's, etc.), because the main purpose of malware is precisely steal data entered in the "logon "authentication system, to operate and thus, fraudulently, steal money from online banking customers. Experiments in the Malware allowed establishing a new method of decryption establishing guidelines to combat its effects describing his fraudulent scheme and operation infection. I propose a general methodology to break the encryption communications malware (keystream), extracting the system used to encrypt such communications and a general approach of the Keystream technique. We show that this methodology can be used to respond to the threat of Zeus and finally provide lessons learned highlighting some general principles of Malware (in general) and in particular proposing Zeus Cronus, an IDS that specifically seeks the Zeus malware, testing it experimentally in a network production and providing an effective skills to combat the Malware are discussed. The thesis is a research interrelated progressive evolution between malware infection systems and authentication methods, reflected in the research work cumulatively, showing an evolution of research output and looking for a progressive improvement of methods authentication and recommendations for prevention and preventing infections, a review of the main app stores for mobile financial services and a proposal to these stores. The most common methods eIDAMS (authentication methods and electronic identification) implemented in Europe and its robustness are analyzed. An analysis of adequacy is presented in terms of efficiency, usability, costs, types of operations and segments including possibilities of use as authentication method with biometrics as innovation.Este trabajo de tesis se ha realizado en el entorno industrial externo a la Universidad como un PhD industrial Los resultados de este PhD han sido testeados, validados, e implementados en el entorno de producción de Caixabank y han sido utilizados como modelos por otras que han seguido las mismas ideas. Las amenazas más candentes contra los bancos en todo el entorno Internet, se basan en herramientas software desarrolladas por los grupos delincuentes, aplicaciones que se ejecutan tanto en entornos web ya sea en el propio ordenador de la víctima (Malware) o en sus dispositivos móviles mediante la descarga de falsas aplicaciones (APP falsa con Malware). Como método se ha utilizado una aproximación de investigación exploratoria cualitativa sobre el problema, la respuesta a este problema y el uso de métodos preventivos a este problema a través de la autenticación. Este método se ha basado en muestras, hechos, encuestas, pruebas de laboratorio, experimentos, pruebas de concepto; en definitiva datos reales de los que se ha podido deducir la tesis propuesta, utilizando tanto investigación de laboratorio como métodos de teoría fundamentada en datos de experimentos pilotos realizados en entornos reales. He estado investigando los diversos aspectos relacionados con e-crime siguiendo una línea de investigación focalizada en temas intrínsecamente relacionadas: - Los métodos, medios y sistemas de ataque: Malware, familias de Malware de troyanos bancarios, casos de usos de Malware, Zeus como caso de uso. - Las plataformas fijas, los móviles y sus aplicaciones como medio para realizar los ataques de Malware. - Métodos forenses para analizar el Malware y su infraestructura de ataque. - Mejora continuada de los métodos de autenticación de los clientes y usuarios como primera barrera de defensa anti- malware. - Uso de la biometría como factor de autenticación innovador. La línea investiga el Malware y sus sistemas de ataque intrínsecamente relacionada con los métodos de autenticación y los sistemas para infectar al cliente (ejecutables, APP's, etc.) porque el objetivo principal del malware es robar precisamente los datos que se introducen en el "logon" del sistema de autenticación para operar de forma fraudulenta y sustraer así el dinero de los clientes de banca electrónica. Los experimentos realizados en el Malware permitieron establecer un método novedoso de descifrado que estableció pautas para combatir sus efectos fraudulentos describiendo su esquema de infección y funcionamiento Propongo una metodología general para romper el cifrado de comunicaciones del malware (keystream) extrayendo el sistema utilizado para cifrar dichas comunicaciones y una generalización de la técnica de Keystream. Se demuestra que esta metodología puede usarse para responder a la amenaza de Zeus y finalmente proveemos lecciones aprendidas resaltando algunos principios generales del Malware (en general) y Zeus en particular proponiendo Cronus, un IDS que persigue específicamente el Malware Zeus, probándolo experimentalmente en una red de producción y se discuten sus habilidades y efectividad. En la tesis hay una evolución investigativa progresiva interrelacionada entre el Malware, sistemas de infección y los métodos de autenticación, que se refleja en los trabajos de investigación de manera acumulativa, mostrando una evolución del output de investigación y buscando una mejora progresiva de los métodos de autenticación y de la prevención y recomendaciones para evitar las infecciones, una revisión de las principales tiendas de Apps para servicios financieros para móviles y una propuesta para estas tiendas. Se analizan los métodos más comunes eIDAMS (Métodos de Autenticación e Identificación electrónica) implementados en Europa y su robustez y presentamos un análisis de adecuación en función de eficiencia, usabilidad, costes, tipos de operación y segmentos incluyendo un análisis de posibilidades con métodos biométricos como innovación.Postprint (published version

A Survey on Modality Characteristics, Performance Evaluation Metrics, and Security for Traditional and Wearable Biometric Systems

Biometric research is directed increasingly towards Wearable Biometric Systems (WBS) for user authentication and identification. However, prior to engaging in WBS research, how their operational dynamics and design considerations differ from those of Traditional Biometric Systems (TBS) must be understood. While the current literature is cognizant of those differences, there is no effective work that summarizes the factors where TBS and WBS differ, namely, their modality characteristics, performance, security and privacy. To bridge the gap, this paper accordingly reviews and compares the key characteristics of modalities, contrasts the metrics used to evaluate system performance, and highlights the divergence in critical vulnerabilities, attacks and defenses for TBS and WBS. It further discusses how these factors affect the design considerations for WBS, the open challenges and future directions of research in these areas. In doing so, the paper provides a big-picture overview of the important avenues of challenges and potential solutions that researchers entering the field should be aware of. Hence, this survey aims to be a starting point for researchers in comprehending the fundamental differences between TBS and WBS before understanding the core challenges associated with WBS and its design