IIFA: Modular Inter-app Intent Information Flow Analysis of Android Applications

Android apps cooperate through message passing via intents. However, when apps do not have identical sets of privileges inter-app communication (IAC) can accidentally or maliciously be misused, e.g., to leak sensitive information contrary to users expectations. Recent research considered static program analysis to detect dangerous data leaks due to inter-component communication (ICC) or IAC, but suffers from shortcomings with respect to precision, soundness, and scalability. To solve these issues we propose a novel approach for static ICC/IAC analysis. We perform a fixed-point iteration of ICC/IAC summary information to precisely resolve intent communication with more than two apps involved. We integrate these results with information flows generated by a baseline (i.e. not considering intents) information flow analysis, and resolve if sensitive data is flowing (transitively) through components/apps in order to be ultimately leaked. Our main contribution is the first fully automatic sound and precise ICC/IAC information flow analysis that is scalable for realistic apps due to modularity, avoiding combinatorial explosion: Our approach determines communicating apps using short summaries rather than inlining intent calls, which often requires simultaneously analyzing all tuples of apps. We evaluated our tool IIFA in terms of scalability, precision, and recall. Using benchmarks we establish that precision and recall of our algorithm are considerably better than prominent state-of-the-art analyses for IAC. But foremost, applied to the 90 most popular applications from the Google Playstore, IIFA demonstrated its scalability to a large corpus of real-world apps. IIFA reports 62 problematic ICC-/IAC-related information flows via two or more apps/components

Neural-Augmented Static Analysis of Android Communication

We address the problem of discovering communication links between applications in the popular Android mobile operating system, an important problem for security and privacy in Android. Any scalable static analysis in this complex setting is bound to produce an excessive amount of false-positives, rendering it impractical. To improve precision, we propose to augment static analysis with a trained neural-network model that estimates the probability that a communication link truly exists. We describe a neural-network architecture that encodes abstractions of communicating objects in two applications and estimates the probability with which a link indeed exists. At the heart of our architecture are type-directed encoders (TDE), a general framework for elegantly constructing encoders of a compound data type by recursively composing encoders for its constituent types. We evaluate our approach on a large corpus of Android applications, and demonstrate that it achieves very high accuracy. Further, we conduct thorough interpretability studies to understand the internals of the learned neural networks.Comment: Appears in Proceedings of the 2018 ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC/FSE

Copyright protection for the electronic distribution of text documents

Each copy of a text document can be made different in a nearly invisible way by repositioning or modifying the appearance of different elements of text, i.e., lines, words, or characters. A unique copy can be registered with its recipient, so that subsequent unauthorized copies that are retrieved can be traced back to the original owner. In this paper we describe and compare several mechanisms for marking documents and several other mechanisms for decoding the marks after documents have been subjected to common types of distortion. The marks are intended to protect documents of limited value that are owned by individuals who would rather possess a legal than an illegal copy if they can be distinguished. We will describe attacks that remove the marks and countermeasures to those attacks. An architecture is described for distributing a large number of copies without burdening the publisher with creating and transmitting the unique documents. The architecture also allows the publisher to determine the identity of a recipient who has illegally redistributed the document, without compromising the privacy of individuals who are not operating illegally. Two experimental systems are described. One was used to distribute an issue of the IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, and the second was used to mark copies of company private memoranda

Twitter data mining for the diagnosis of leaks in drinking water distribution networks

This article presents a methodology for using data from social networks, specifically from Twitter, to diagnose leaks in drinking water distribution networks. The methodology involves the collection of tweets from citizens reporting leaks, the extraction of information from the tweets, and the processing of such information to run the diagnosis. To demonstrate the viability of this methodology, 358 Twitter leak reports were collected and analyzed in Mexico City from 1 May to 31 December 2022. From these reports, leak density and probability were calculated, which are metrics that can be used to develop forecasting algorithms, identify root causes, and program repairs. The calculated metrics were compared with those calculated through telephone reports provided by SACMEX, the entity that manages water in Mexico City. Results show that metrics obtained from Twitter and phone reports were highly comparable, indicating the usefulness and reliability of social media data for diagnosing leaks

Novel architectures and strategies for security offloading

Internet has become an indispensable and powerful tool in our modern society. Its ubiquitousness, pervasiveness and applicability have fostered paradigm changes around many aspects of our lives. This phenomena has positioned the network and its services as fundamental assets over which we rely and trust. However, Internet is far from being perfect. It has considerable security issues and vulnerabilities that jeopardize its main core functionalities with negative impact over its players. Furthermore, these vulnerabilities¿ complexities have been amplified along with the evolution of Internet user mobility. In general, Internet security includes both security for the correct network operation and security for the network users and endpoint devices. The former involves the challenges around the Internet core control and management vulnerabilities, while the latter encompasses security vulnerabilities over end users and endpoint devices. Similarly, Internet mobility poses major security challenges ranging from routing complications, connectivity disruptions and lack of global authentication and authorization. The purpose of this thesis is to present the design of novel architectures and strategies for improving Internet security in a non-disruptive manner. Our novel security proposals follow a protection offloading approach. The motives behind this paradigm target the further enhancement of the security protection while minimizing the intrusiveness and disturbance over the Internet routing protocols, its players and users. To accomplish such level of transparency, the envisioned solutions leverage on well-known technologies, namely, Software Defined Networks, Network Function Virtualization and Fog Computing. From the Internet core building blocks, we focus on the vulnerabilities of two key routing protocols that play a fundamental role in the present and the future of the Internet, i.e., the Border Gateway Protocol (BGP) and the Locator-Identifier Split Protocol (LISP). To this purpose, we first investigate current BGP vulnerabilities and countermeasures with emphasis in an unresolved security issue defined as Route Leaks. Therein, we discuss the reasons why different BGP security proposals have failed to be adopted, and the necessity to propose innovative solutions that minimize the impact over the already deployed routing solution. To this end, we propose pragmatic security methodologies to offload the protection with the following advantages: no changes to the BGP protocol, neither dependency on third party information nor on third party security infrastructure, and self-beneficial. Similarly, we research the current LISP vulnerabilities with emphasis on its control plane and mobility support. We leverage its by-design separation of control and data planes to propose an enhanced location-identifier registration process of end point identifiers. This proposal improves the mobility of end users with regards on securing a dynamic traffic steering over the Internet. On the other hand, from the end user and devices perspective we research new paradigms and architectures with the aim of enhancing their protection in a more controllable and consolidated manner. To this end, we propose a new paradigm which shifts the device-centric protection paradigm toward a user-centric protection. Our proposal focus on the decoupling or extending of the security protection from the end devices toward the network edge. It seeks the homogenization of the enforced protection per user independently of the device utilized. We further investigate this paradigm in a mobility user scenario. Similarly, we extend this proposed paradigm to the IoT realm and its intrinsic security challenges. Therein, we propose an alternative to protect both the things, and the services that leverage from them by consolidating the security at the network edge. We validate our proposal by providing experimental results from prof-of-concepts implementations.Internet se ha convertido en una poderosa e indispensable herramienta para nuestra sociedad moderna. Su omnipresencia y aplicabilidad han promovido grandes cambios en diferentes aspectos de nuestras vidas. Este fenómeno ha posicionado a la red y sus servicios como activos fundamentales sobre los que contamos y confiamos. Sin embargo, Internet está lejos de ser perfecto. Tiene considerables problemas de seguridad y vulnerabilidades que ponen en peligro sus principales funcionalidades. Además, las complejidades de estas vulnerabilidades se han ampliado junto con la evolución de la movilidad de usuarios de Internet y su limitado soporte. La seguridad de Internet incluye tanto la seguridad para el correcto funcionamiento de la red como la seguridad para los usuarios y sus dispositivos. El primero implica los desafíos relacionados con las vulnerabilidades de control y gestión de la infraestructura central de Internet, mientras que el segundo abarca las vulnerabilidades de seguridad sobre los usuarios finales y sus dispositivos. Del mismo modo, la movilidad en Internet plantea importantes desafíos de seguridad que van desde las complicaciones de enrutamiento, interrupciones de la conectividad y falta de autenticación y autorización globales. El propósito de esta tesis es presentar el diseño de nuevas arquitecturas y estrategias para mejorar la seguridad de Internet de una manera no perturbadora. Nuestras propuestas de seguridad siguen un enfoque de desacople de la protección. Los motivos detrás de este paradigma apuntan a la mejora adicional de la seguridad mientras que minimizan la intrusividad y la perturbación sobre los protocolos de enrutamiento de Internet, sus actores y usuarios. Para lograr este nivel de transparencia, las soluciones previstas aprovechan nuevas tecnologías, como redes definidas por software (SDN), virtualización de funciones de red (VNF) y computación en niebla. Desde la perspectiva central de Internet, nos centramos en las vulnerabilidades de dos protocolos de enrutamiento clave que desempeñan un papel fundamental en el presente y el futuro de Internet, el Protocolo de Puerta de Enlace Fronterizo (BGP) y el Protocolo de Separación Identificador/Localizador (LISP ). Para ello, primero investigamos las vulnerabilidades y medidas para contrarrestar un problema no resuelto en BGP definido como Route Leaks. Proponemos metodologías pragmáticas de seguridad para desacoplar la protección con las siguientes ventajas: no cambios en el protocolo BGP, cero dependencia en la información de terceros, ni de infraestructura de seguridad de terceros, y de beneficio propio. Del mismo modo, investigamos las vulnerabilidades actuales sobre LISP con énfasis en su plano de control y soporte de movilidad. Aprovechamos la separacçón de sus planos de control y de datos para proponer un proceso mejorado de registro de identificadores de ubicación y punto final, validando de forma segura sus respectivas autorizaciones. Esta propuesta mejora la movilidad de los usuarios finales con respecto a segurar un enrutamiento dinámico del tráfico a través de Internet. En paralelo, desde el punto de vista de usuarios finales y dispositivos investigamos nuevos paradigmas y arquitecturas con el objetivo de mejorar su protección de forma controlable y consolidada. Con este fin, proponemos un nuevo paradigma hacia una protección centrada en el usuario. Nuestra propuesta se centra en el desacoplamiento o ampliación de la protección de seguridad de los dispositivos finales hacia el borde de la red. La misma busca la homogeneización de la protección del usuario independientemente del dispositivo utilizado. Además, investigamos este paradigma en un escenario con movilidad. Validamos nuestra propuesta proporcionando resultados experimentales obtenidos de diferentes experimentos y pruebas de concepto implementados

Novel architectures and strategies for security offloading

Internet has become an indispensable and powerful tool in our modern society. Its ubiquitousness, pervasiveness and applicability have fostered paradigm changes around many aspects of our lives. This phenomena has positioned the network and its services as fundamental assets over which we rely and trust. However, Internet is far from being perfect. It has considerable security issues and vulnerabilities that jeopardize its main core functionalities with negative impact over its players. Furthermore, these vulnerabilities¿ complexities have been amplified along with the evolution of Internet user mobility. In general, Internet security includes both security for the correct network operation and security for the network users and endpoint devices. The former involves the challenges around the Internet core control and management vulnerabilities, while the latter encompasses security vulnerabilities over end users and endpoint devices. Similarly, Internet mobility poses major security challenges ranging from routing complications, connectivity disruptions and lack of global authentication and authorization. The purpose of this thesis is to present the design of novel architectures and strategies for improving Internet security in a non-disruptive manner. Our novel security proposals follow a protection offloading approach. The motives behind this paradigm target the further enhancement of the security protection while minimizing the intrusiveness and disturbance over the Internet routing protocols, its players and users. To accomplish such level of transparency, the envisioned solutions leverage on well-known technologies, namely, Software Defined Networks, Network Function Virtualization and Fog Computing. From the Internet core building blocks, we focus on the vulnerabilities of two key routing protocols that play a fundamental role in the present and the future of the Internet, i.e., the Border Gateway Protocol (BGP) and the Locator-Identifier Split Protocol (LISP). To this purpose, we first investigate current BGP vulnerabilities and countermeasures with emphasis in an unresolved security issue defined as Route Leaks. Therein, we discuss the reasons why different BGP security proposals have failed to be adopted, and the necessity to propose innovative solutions that minimize the impact over the already deployed routing solution. To this end, we propose pragmatic security methodologies to offload the protection with the following advantages: no changes to the BGP protocol, neither dependency on third party information nor on third party security infrastructure, and self-beneficial. Similarly, we research the current LISP vulnerabilities with emphasis on its control plane and mobility support. We leverage its by-design separation of control and data planes to propose an enhanced location-identifier registration process of end point identifiers. This proposal improves the mobility of end users with regards on securing a dynamic traffic steering over the Internet. On the other hand, from the end user and devices perspective we research new paradigms and architectures with the aim of enhancing their protection in a more controllable and consolidated manner. To this end, we propose a new paradigm which shifts the device-centric protection paradigm toward a user-centric protection. Our proposal focus on the decoupling or extending of the security protection from the end devices toward the network edge. It seeks the homogenization of the enforced protection per user independently of the device utilized. We further investigate this paradigm in a mobility user scenario. Similarly, we extend this proposed paradigm to the IoT realm and its intrinsic security challenges. Therein, we propose an alternative to protect both the things, and the services that leverage from them by consolidating the security at the network edge. We validate our proposal by providing experimental results from prof-of-concepts implementations.Internet se ha convertido en una poderosa e indispensable herramienta para nuestra sociedad moderna. Su omnipresencia y aplicabilidad han promovido grandes cambios en diferentes aspectos de nuestras vidas. Este fenómeno ha posicionado a la red y sus servicios como activos fundamentales sobre los que contamos y confiamos. Sin embargo, Internet está lejos de ser perfecto. Tiene considerables problemas de seguridad y vulnerabilidades que ponen en peligro sus principales funcionalidades. Además, las complejidades de estas vulnerabilidades se han ampliado junto con la evolución de la movilidad de usuarios de Internet y su limitado soporte. La seguridad de Internet incluye tanto la seguridad para el correcto funcionamiento de la red como la seguridad para los usuarios y sus dispositivos. El primero implica los desafíos relacionados con las vulnerabilidades de control y gestión de la infraestructura central de Internet, mientras que el segundo abarca las vulnerabilidades de seguridad sobre los usuarios finales y sus dispositivos. Del mismo modo, la movilidad en Internet plantea importantes desafíos de seguridad que van desde las complicaciones de enrutamiento, interrupciones de la conectividad y falta de autenticación y autorización globales. El propósito de esta tesis es presentar el diseño de nuevas arquitecturas y estrategias para mejorar la seguridad de Internet de una manera no perturbadora. Nuestras propuestas de seguridad siguen un enfoque de desacople de la protección. Los motivos detrás de este paradigma apuntan a la mejora adicional de la seguridad mientras que minimizan la intrusividad y la perturbación sobre los protocolos de enrutamiento de Internet, sus actores y usuarios. Para lograr este nivel de transparencia, las soluciones previstas aprovechan nuevas tecnologías, como redes definidas por software (SDN), virtualización de funciones de red (VNF) y computación en niebla. Desde la perspectiva central de Internet, nos centramos en las vulnerabilidades de dos protocolos de enrutamiento clave que desempeñan un papel fundamental en el presente y el futuro de Internet, el Protocolo de Puerta de Enlace Fronterizo (BGP) y el Protocolo de Separación Identificador/Localizador (LISP ). Para ello, primero investigamos las vulnerabilidades y medidas para contrarrestar un problema no resuelto en BGP definido como Route Leaks. Proponemos metodologías pragmáticas de seguridad para desacoplar la protección con las siguientes ventajas: no cambios en el protocolo BGP, cero dependencia en la información de terceros, ni de infraestructura de seguridad de terceros, y de beneficio propio. Del mismo modo, investigamos las vulnerabilidades actuales sobre LISP con énfasis en su plano de control y soporte de movilidad. Aprovechamos la separacçón de sus planos de control y de datos para proponer un proceso mejorado de registro de identificadores de ubicación y punto final, validando de forma segura sus respectivas autorizaciones. Esta propuesta mejora la movilidad de los usuarios finales con respecto a segurar un enrutamiento dinámico del tráfico a través de Internet. En paralelo, desde el punto de vista de usuarios finales y dispositivos investigamos nuevos paradigmas y arquitecturas con el objetivo de mejorar su protección de forma controlable y consolidada. Con este fin, proponemos un nuevo paradigma hacia una protección centrada en el usuario. Nuestra propuesta se centra en el desacoplamiento o ampliación de la protección de seguridad de los dispositivos finales hacia el borde de la red. La misma busca la homogeneización de la protección del usuario independientemente del dispositivo utilizado. Además, investigamos este paradigma en un escenario con movilidad. Validamos nuestra propuesta proporcionando resultados experimentales obtenidos de diferentes experimentos y pruebas de concepto implementados.Postprint (published version