Protection against Code Obfuscation Attacks based on control dependencies in Android Systems

International audienceIn Android systems, an attacker can obfuscate an application code to leak sensitive information. TaintDroid is an information flow tracking system that protects private data in smartphones. But, TainDroid cannot detect control flows. Thus, it can be circumvented by an obfuscated code attack based on control dependencies. In this paper, we present a collection of obfuscated code attacks on TaintDroid system. We propose a technical solution based on a hybrid approach that combines static and dynamic analysis. We formally specify our solution based on two propagation rules. Finally, we evaluate our approach and show that we can avoid the obfuscated code attacks based on control dependencies by using these propagation rules

Detection of illegal control flow in Android System: Protecting private data used by Smartphone Apps

International audienceToday, security is a requirement for smartphone operating systems that are used to store and handle sensitive information. How- ever, smartphone users usually download third-party applications that can leak personal data without user authorization. For this reason, the dynamic taint analysis mechanism is used to control the manipulation of private data by third-party apps [9]. But this technique does not detect control flows. In particular, untrusted applications can circumvent An- droid system and get privacy sensitive information through control flows. In this paper, we propose a hybrid approach that combines static and dynamic analysis to propagate taint along control dependencies in An- droid system. To evaluate the effectiveness of our approach, we analyse 27 free Android applications. We found that 14 of these applications use control flows to transfer sensitive data. We successfully detect that 8 of them leaked private information. Our approach creates 19% performance overhead that is due to the propagation of taint in the control flow. By using our approach, it becomes possible to detect leakage of personal data through control flows

Community health agent: a literature review

Este é um estudo de revisão da literatura sobre o Agente Comunitário de Saúde brasileiro. A metodologia usada foi o estudo exploratório-descritivo, utilizando-se o banco de dados LILACS (de 1982 até 2005) e MEDLINE (1966 a 2005). A análise resultou em 153 publicações, sendo 97 excluídas. Quanto ao tipo de produção, das 56 referências (100%), 53,6% eram livros, 32,1% artigos de periódicos, 7,1% dissertações de mestrado e os restantes, 7,2%, teses de doutorado e monografias de especialização. Observou-se que 59% das referências foram incluídas na base de dados a partir de 2000. Considerando-se artigos de periódicos, monografias de especialização, dissertações de mestrado e teses de doutorado, no total de 26 estudos, houve predomínio do delineamento experimental (73%), sendo os objetivos mais freqüentes: caracterização dos agentes e de suas funções, avaliação do processo e resultados do trabalho. Os dados sugerem interesse crescente sobre o tema, embora os agentes sejam ainda uma população pouco estudada.Estudio de literatura de revisión sobre Agente Comunitario de Salud brasileiro. La metodología era estudio descriptivo y exploratório, en base de datos LILACS (1982 a 2005) y MEDLINE (1966 a 2005). El análisis resultó 153 publicaciones, 97 excluidos. De las 56 referencias (100%), 53,6% eran los libros, 32,1% artículos de periódicos, 7,1% eran disertaciones de maestría y del resto 7,2%, las tesis de doctorado y monografías de especialización. El 59% de las referencias habían sido incluidos en la base de datos en 2000. Considerando los artículos periódicos, las monografías de especialización, dissertaciones de maestría y tesis de doctorado (26 estudios), el diseño experimental predominó (73%), siendo los objetivos más frecuentes: caracterización de los agentes y de sus funciones, evaluaciónes del proceso y de los resultados del trabajo. Los datos sugieren interés de aumento en el tema, estos trabajadores todavía consisten una población poco estudiada.Study of the review literature regarding brazilian Community Health Agent. The methodology was descriptive and exploratory study, using the LILACS database (1982 to march/2005) and MEDLINE (1966 to 2005). The analysis resulted 153 publications, from which 97 had been excluded. About type of production, of the 56 references (100%), 53,6% were books, 32,1% periodic articles, 7,1% Master's Theses and remains 7,2%, doctoral dissertations and specialization monographs. It was observed that 59% of the references had been enclosed in the database in 2000. Considering only periodic articles, specialization monographs, Master's Theses and doctoral dissertations, an amount of 26 studies, the experimental design predominated (73%), being the objectives most frequent: characterization of the agents and their functions, process work and results. The data suggest increasing interest on the subject, however, these workers still consist a population little studied

Drosophila melanogaster dHCF Interacts with both PcG and TrxG Epigenetic Regulators

Repression and activation of gene transcription involves multiprotein complexes that modify chromatin structure. The integration of these complexes at regulatory sites can be assisted by co-factors that link them to DNA-bound transcriptional regulators. In humans, one such co-factor is the herpes simplex virus host-cell factor 1 (HCF-1), which is implicated in both activation and repression of transcription. We show here that disruption of the gene encoding the Drosophila melanogaster homolog of HCF-1, dHCF, leads to a pleiotropic phenotype involving lethality, sterility, small size, apoptosis, and morphological defects. In Drosophila, repressed and activated transcriptional states of cell fate-determining genes are maintained throughout development by Polycomb Group (PcG) and Trithorax Group (TrxG) genes, respectively. dHCF mutant flies display morphological phenotypes typical of TrxG mutants and dHCF interacts genetically with both PcG and TrxG genes. Thus, dHCF inactivation enhances the mutant phenotypes of the Pc PcG as well as brm and mor TrxG genes, suggesting that dHCF possesses Enhancer of TrxG and PcG (ETP) properties. Additionally, dHCF interacts with the previously established ETP gene skd. These pleiotropic phenotypes are consistent with broad roles for dHCF in both activation and repression of transcription during fly development

Qualidade de Vida no Trabalho: Uma Revisão Da Produção Científica

O trabalho tem como objetivo analisar a produção científica sobre o tema Qualidade de Vida no Trabalho. Metodologia: trata-se de um estudo de revisão, sendo que foi utilizada a base de dados LILACS, entre 1989 e abril de 2005. A análise resultou 44 referências, sendo que os resumos constituíram o material base. Resultados: Quanto ao país de origem, das 44 referências analisadas (100%), 72,7% eram nacionais, 36,4% foram publicadas entre os anos de 2001 e 2005 e 54,5% eram artigos de periódicos. Considerando somente artigos de periódicos, monografias de especialização, dissertações de mestrado e teses de doutorado, com 37 estudos, o desenho exploratório predominou (67,6%), sendo o objetivo mais freqüente, 35,2%, a avaliação da qualidade de vida, geral ou no trabalho. Os sujeitos estudados, os instrumentos utilizados e a distribuição dos artigos nos diferentes periódicos também foram analisados. Conclusão: Este estudo oferece direções para pesquisas futuras e indica preocupações, como o pequeno número de estudos sobre o tema.