Fine-Grained Access Control Within NoSQL Document-Oriented Datastores

The recent years have seen the birth of several NoSQL datastores, which are getting more and more popularity for their ability to handle high volumes of heterogeneous and unstructured data in a very efficient way. In several cases, NoSQL databases proved to outclass in terms of performance, scalability, and ease of use relational database management systems, meeting the requirements of a variety of today ICT applications. However, recent surveys reveal that, despite their undoubted popularity, NoSQL datastores suffer from some weaknesses, among which the lack of effective support for data protection appears among the most serious ones. Proper data protection mechanisms are therefore required to fill this void. In this work, we start to address this issue by focusing on access control and discussing the definition of a fine-grained access control framework for document-oriented NoSQL datastores. More precisely, we first focus on issues and challenges related to the definition of such a framework, considering theoretical, implementation, and integration aspects. Then, we discuss the reasons for which state-of-the-art fine-grained access control solutions proposed for relational database management systems cannot be used within the NoSQL scenario. We then introduce possible strategies to address the identified issues, which are at the basis of the framework development. Finally, we shortly report the outcome of an experience where the proposed framework has been used to enhance the data protection features of a popular NoSQL database

Building Context-Aware Access Control In Enterprise Ontologies

Knowledge centric management (KCM) has become a key strategy for competitive edge. As an essential of KCM, an enterprise ontology represents the knowledge of an organization. Thus, the need for securing enterprise ontologies (EO) becomes imperative. Adequate access control is a major component of ontology security. However, access control for EO is largely neglected in information systems (IS) literature. This paper presents the first research to fill this gap. I propose five requirements for good access-control solutions for EO. The proposed solution offers an architecture framework that meets the five requirements. Semantic Web technology is used to build context-aware access controls into EO. My proposal includes a novel resolution for policy conflicts. This study provides the first design of fine-grained and dynamically-adjusted access authorizations

Access control technologies for Big Data management systems: literature review and future trends

Abstract Data security and privacy issues are magnified by the volume, the variety, and the velocity of Big Data and by the lack, up to now, of a reference data model and related data manipulation languages. In this paper, we focus on one of the key data security services, that is, access control, by highlighting the differences with traditional data management systems and describing a set of requirements that any access control solution for Big Data platforms may fulfill. We then describe the state of the art and discuss open research issues

Retrofitting privacy controls to stock Android

Android ist nicht nur das beliebteste Betriebssystem für mobile Endgeräte, sondern auch ein ein attraktives Ziel für Angreifer. Um diesen zu begegnen, nutzt Androids Sicherheitskonzept App-Isolation und Zugangskontrolle zu kritischen Systemressourcen. Nutzer haben dabei aber nur wenige Optionen, App-Berechtigungen gemäß ihrer Bedürfnisse einzuschränken, sondern die Entwickler entscheiden über zu gewährende Berechtigungen. Androids Sicherheitsmodell kann zudem nicht durch Dritte angepasst werden, so dass Nutzer zum Schutz ihrer Privatsphäre auf die Gerätehersteller angewiesen sind. Diese Dissertation präsentiert einen Ansatz, Android mit umfassenden Privatsphäreeinstellungen nachzurüsten. Dabei geht es konkret um Techniken, die ohne Modifikationen des Betriebssystems oder Zugriff auf Root-Rechte auf regulären Android-Geräten eingesetzt werden können. Der erste Teil dieser Arbeit etabliert Techniken zur Durchsetzung von Sicherheitsrichtlinien für Apps mithilfe von inlined reference monitors. Dieser Ansatz wird durch eine neue Technik für dynamic method hook injection in Androids Java VM erweitert. Schließlich wird ein System eingeführt, das prozessbasierte privilege separation nutzt, um eine virtualisierte App-Umgebung zu schaffen, um auch komplexe Sicherheitsrichtlinien durchzusetzen. Eine systematische Evaluation unseres Ansatzes konnte seine praktische Anwendbarkeit nachweisen und mehr als eine Million Downloads unserer Lösung zeigen den Bedarf an praxisgerechten Werkzeugen zum Schutz der Privatsphäre.Android is the most popular operating system for mobile devices, making it a prime target for attackers. To counter these, Android’s security concept uses app isolation and access control to critical system resources. However, Android gives users only limited options to restrict app permissions according to their privacy preferences but instead lets developers dictate the permissions users must grant. Moreover, Android’s security model is not designed to be customizable by third-party developers, forcing users to rely on device manufacturers to address their privacy concerns. This thesis presents a line of work that retrofits comprehensive privacy controls to the Android OS to put the user back in charge of their device. It focuses on developing techniques that can be deployed to stock Android devices without firmware modifications or root privileges. The first part of this dissertation establishes fundamental policy enforcement on thirdparty apps using inlined reference monitors to enhance Android’s permission system. This approach is then refined by introducing a novel technique for dynamic method hook injection on Android’s Java VM. Finally, we present a system that leverages process-based privilege separation to provide a virtualized application environment that supports the enforcement of complex security policies. A systematic evaluation of our approach demonstrates its practical applicability, and over one million downloads of our solution confirm user demand for privacy-enhancing tools

Runtime values driven by access control policies: statically enforced at the level of relational business tiers

Access control is a key challenge in software engineering, especially in relational database applications. Current access control techniques are based on additional security layers designed by security experts. These additional security layers do not take into account the necessary business logic leading to a separation between business tiers and access control mechanisms. Moreover, business tiers are built from commercial tools (ex: Hibernate, JDBC, ODBC, LINQ), which are not tailored to deal with security aspects. To overcome this situation several proposals have been presented. In spite of their relevance, they do not support the enforcement of access control policies at the level of the runtime values that are used to interact with protected data. Runtime values are critical entities because they play a key role in the process of defining which data is accessed. In this paper, we present a general technique for static checking, at the business tier level, the runtime values that are used to interact with databases and in accordance with the established access control policies. The technique is applicable to CRUD (create, read, update and delete) expressions and also to actions (update and insert) that are executed on data retrieved by Select expressions. A proof of concept is also presented. It uses an access control platform previously developed, which lacks the key issue of this paper. The collected results show that the presented approach is an effective solution to enforce access control policies at the level of runtime values that are used to interact with data residing in relational databases.(undefined

Distributed and typed role-based access control mechanisms driven by CRUD expressions

Business logics of relational databases applications are an important source of security violations, namely in respect to access control. The situation is particularly critical when access control policies are many and complex. In these cases, programmers of business logics can hardly master the established access control policies. Now we consider situations where business logics are built with tools such as JDBC and ODBC. These tools convey two sources of security threats: 1) the use of unauthorized Create, Read, Update and Delete (CRUD) expressions and also 2) the modification of data previously retrieved by Select statements. To overcome this security gap when Role-based access control policies are used, we propose an extension to the basic model in order to control the two sources of security threats. Finally, we present a software architectural model from which distributed and typed RBAC mechanisms are automatically built, this way relieving programmers from mastering any security schema. We demonstrate empirical evidence of the effectiveness of our proposal from a use case based on Java and JDBC