Before-Commit Client State Management Services for AJAX Applications

Heavily script-based browser applications change the manner in which users interact with Web browsers. Instead of downloading a succession of HTML pages, users download a single application and use that application for a long period of time. The application is not a set of HTML pages, but rather a single page that can possible modify its own presentation based on data exchanged with a server. In such an environment, it is necessary to provide some means for the client to manage its own state. We describe the initial results of our work in providing client-side state management services for these script-based applications. We focus on browser-based services that can help the user before any data is committed on the server. Our services include state checkpointing, property binding, operation logging, operational replay, ATOM/RSS data updates, and application-controlled persistence

PerfWeb: How to Violate Web Privacy with Hardware Performance Events

The browser history reveals highly sensitive information about users, such as financial status, health conditions, or political views. Private browsing modes and anonymity networks are consequently important tools to preserve the privacy not only of regular users but in particular of whistleblowers and dissidents. Yet, in this work we show how a malicious application can infer opened websites from Google Chrome in Incognito mode and from Tor Browser by exploiting hardware performance events (HPEs). In particular, we analyze the browsers' microarchitectural footprint with the help of advanced Machine Learning techniques: k-th Nearest Neighbors, Decision Trees, Support Vector Machines, and in contrast to previous literature also Convolutional Neural Networks. We profile 40 different websites, 30 of the top Alexa sites and 10 whistleblowing portals, on two machines featuring an Intel and an ARM processor. By monitoring retired instructions, cache accesses, and bus cycles for at most 5 seconds, we manage to classify the selected websites with a success rate of up to 86.3%. The results show that hardware performance events can clearly undermine the privacy of web users. We therefore propose mitigation strategies that impede our attacks and still allow legitimate use of HPEs

Mobile support in CSCW applications and groupware development frameworks

Computer Supported Cooperative Work (CSCW) is an established subset of the field of Human Computer Interaction that deals with the how people use computing technology to enhance group interaction and collaboration. Mobile CSCW has emerged as a result of the progression from personal desktop computing to the mobile device platforms that are ubiquitous today. CSCW aims to not only connect people and facilitate communication through using computers; it aims to provide conceptual models coupled with technology to manage, mediate, and assist collaborative processes. Mobile CSCW research looks to fulfil these aims through the adoption of mobile technology and consideration for the mobile user. Facilitating collaboration using mobile devices brings new challenges. Some of these challenges are inherent to the nature of the device hardware, while others focus on the understanding of how to engineer software to maximize effectiveness for the end-users. This paper reviews seminal and state-of-the-art cooperative software applications and development frameworks, and their support for mobile devices

A Secure Mobile-based Authentication System

Financial information is extremely sensitive. Hence, electronic banking must provide a robust system to authenticate its customers and let them access their data remotely. On the other hand, such system must be usable, affordable, and portable.We propose a challengeresponse based one-time password (OTP) scheme that uses symmetric cryptography in combination with a hardware security module. The proposed protocol safeguards passwords from keyloggers and phishing attacks. Besides, this solution provides convenient mobility for users who want to bank online anytime and anywhere, not just from their own trusted computers.La informació financera és extremadament sensible. Per tant, la banca electrònica ha de proporcionar un sistema robust per autenticar als seus clients i fer-los accedir a les dades de forma remota. D'altra banda, aquest sistema ha de ser usable, accessible, i portàtil. Es proposa una resposta al desafiament basat en una contrasenya única (OTP), esquema que utilitza la criptografia simètrica en combinació amb un mòdul de maquinari de seguretat. Amés, aquesta solució ofereix mobilitat convenient per als usuaris que volen bancària en línia en qualsevol moment i en qualsevol lloc, no només des dels seus propis equips de confiança.La información financiera es extremadamente sensible. Por lo tanto, la banca electrónica debe proporcionar un sistema robusto para autenticar a sus clientes y hacerles acceder a sus datos de forma remota. Por otra parte, dicho sistema debe ser usable, accesible, y portátil. Se propone una respuesta al desafío basado en una contraseña única (OTP), esquema que utiliza la criptografía simétrica en combinación con un módulo hardware de seguridad hardware. Además, esta solución ofrece una movilidad conveniente para los usuarios que quieren la entidad bancaria en línea en cualquier momento y en cualquier lugar, no sólo des de sus propios equipos de confianza

PALPAS - PAsswordLess PAssword Synchronization

Tools that synchronize passwords over several user devices typically store the encrypted passwords in a central online database. For encryption, a low-entropy, password-based key is used. Such a database may be subject to unauthorized access which can lead to the disclosure of all passwords by an offline brute-force attack. In this paper, we present PALPAS, a secure and user-friendly tool that synchronizes passwords between user devices without storing information about them centrally. The idea of PALPAS is to generate a password from a high entropy secret shared by all devices and a random salt value for each service. Only the salt values are stored on a server but not the secret. The salt enables the user devices to generate the same password but is statistically independent of the password. In order for PALPAS to generate passwords according to different password policies, we also present a mechanism that automatically retrieves and processes the password requirements of services. PALPAS users need to only memorize a single password and the setup of PALPAS on a further device demands only a one-time transfer of few static data.Comment: An extended abstract of this work appears in the proceedings of ARES 201