ABSTRACT Smartphones are now ubiquitous. However, the security requirements of these relatively new systems and the applications they support are still being understood. As a result, the security infrastructure available in current smartphone operating systems is largely underdeveloped. In this paper, we consider the security requirements of smartphone applications and augment the existing Android operating system with a framework to meet them. We present Secure Application INTeraction (Saint), a modified infrastructure that governs install‐time permission assignment and their run‐time use as dictated by application provider policy. An in‐depth description of the semantics of application policy is presented. The architecture and technical detail of Saint are given, and areas for extension, optimization, and improvement are explored. We demonstrate through a concrete example and study of real‐world applications that Saint provides necessary utility for applications to assert and control the security decisions on the platform. Copyright © 2011 John Wiley & Sons, Ltd.

The penetration of cellular networks worldwide and emergence of smart phones has led to a revolution in mobile content. Users consume diverse content when, for example, exchanging photos, playing games, browsing websites, and viewing multimedia. Current phone platforms provide protections for user privacy, the cellular radio, and the integrity of the OS itself. However, few offer protections to protect the content once it enters the phone. For example, MP3-based MMS or photo content placed on Android smart phones can be extracted and shared with impunity. In this paper, we explore the requirements and enforcement of digital rights management (DRM) policy on smart phones. An analysis of the Android market shows that DRM services should ensure: a) protected content is accessible only by authorized phones b) content is only accessible by provider-endorsed applications, and c) access is regulated by contextual constraints, e.g., used for a limited time, a maximum number of viewings, etc. The Porscha system developed in this work places content proxies and reference monitors within the Android middleware to enforce DRM policies embedded in received content. A pilot study controlling content obtained over SMS, MMS, and email illustrates the expressibility and enforcement of Porscha policies. Our experiments demonstrate that Porscha is expressive enough to articulate needed DRM policies and that their enforcement has limited impact on performance.

Smartphones are now ubiquitous. However, the security requirements of these relatively new systems and the applications they support are still being understood. As a result, the security infrastructure available in current smartphone operating systems is largely underdeveloped. In this paper, we consider the security requirements of smartphone applications and augment the existing Android operating system with a framework to meet them. We present Secure Application INTeraction (Saint), a modified infrastructure that governs install-time permission assignment and their run-time use as dictated by application provider policy. An in-depth description of the semantics of application policy is presented. The architecture and technical detail of Saint is given, and areas for extension, optimization, and improvement explored. As we show through concrete example, Saint provides necessary utility for applications to assert and control the security decisions on the platform.

Users have begun downloading an increasingly large number of mobile phone applications in response to advancements in handsets and wireless networks. The increased number of applications results in a greater chance of installing Trojans and similar malware. In this paper, we propose the Kirin security service for Android, which performs lightweight certification of applications to mitigate malware at install time. Kirin certification uses security rules, which are templates designed to conservatively match undesirable properties in security configuration bundled with applications. We use a variant of security requirements engineering techniques to perform an in-depth security analysis of Android to produce a set of rules that match malware characteristics. In a sample of 311 of the most popular applications downloaded from the official Android Market, Kirin and our rules found 5 applications that implement dangerous functionality and therefore should be installed with extreme caution. Upon close inspection, another five applications asserted dangerous rights, but were within the scope of reasonable functional needs. These results indicate that security configuration bundled with Android applications provides practical means of detecting malware.

The vast expansion of interconnectivity with the Internet and the rapid evolution of highly-capable but largely insecure mobile devices threatens cellular networks. In this paper, we characterize the impact of the large scale compromise and coordination of mobile phones in attacks against the core of these networks. Through a combination of measurement, simulation and analysis, we demonstrate the ability of a botnet composed of as few as 11,750 compromised mobile phones to degrade service to area-code sized regions by 93%. As such attacks are accomplished through the execution of network service requests and not a constant stream of phone calls, users are unlikely to be aware of their occurrence. We then investigate a number of significant network bottlenecks, their impact on the density of compromised nodes per base station and how they can be avoided. We conclude by discussing a number of countermeasures that may help to partially mitigate the threats posed by such attacks.

Pervasive computing enables seamless integration of computing technology into everyday life to make up-to-date information and services proactively available to the users based on their needs and behaviors. We aim to develop a transaction management scheme as a pertinent component for such environment supported by either structured or ad hoc networks. We propose transactional agents for pervasive computing (TAPCO), which utilizes a dynamic hierarchical meta data structure that captures the semantic contents of the underlying heterogeneous data sources. Mobile agents process the transactions collaboratively, to preserve ACID properties without violating local autonomy of the data sources. TAPCO is simulated and compared against decentralized serialization graph testing (DSGT) protocol. The results show that TAPCO outperforms DSGT in several ways. In contrast to DSGT that did not consider local transactions, TAPCO supports both local and global transactions without violating the local autonomy.