6 research outputs found

    Toward least-privilege isolation for software

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    Hackers leverage software vulnerabilities to disclose, tamper with, or destroy sensitive data. To protect sensitive data, programmers can adhere to the principle of least-privilege, which entails giving software the minimal privilege it needs to operate, which ensures that sensitive data is only available to software components on a strictly need-to-know basis. Unfortunately, applying this principle in practice is dif- �cult, as current operating systems tend to provide coarse-grained mechanisms for limiting privilege. Thus, most applications today run with greater-than-necessary privileges. We propose sthreads, a set of operating system primitives that allows �ne-grained isolation of software to approximate the least-privilege ideal. sthreads enforce a default-deny model, where software components have no privileges by default, so all privileges must be explicitly granted by the programmer. Experience introducing sthreads into previously monolithic applications|thus, partitioning them|reveals that enumerating privileges for sthreads is di�cult in practice. To ease the introduction of sthreads into existing code, we include Crowbar, a tool that can be used to learn the privileges required by a compartment. We show that only a few changes are necessary to existing code in order to partition applications with sthreads, and that Crowbar can guide the programmer through these changes. We show that applying sthreads to applications successfully narrows the attack surface by reducing the amount of code that can access sensitive data. Finally, we show that applications using sthreads pay only a small performance overhead. We applied sthreads to a range of applications. Most notably, an SSL web server, where we show that sthreads are powerful enough to protect sensitive data even against a strong adversary that can act as a man-in-the-middle in the network, and also exploit most code in the web server; a threat model not addressed to date

    Political artifacts and personal privacy : the Yenta multi-agent distributed matchmaking system

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    Thesis (Ph.D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 1999.Includes bibliographical references (p. 119-128).Technology does not exist in a social vacuum. The design and patterns of use of any particular technological artifact have implications both for the direct users of the technology, and for society at large. Decisions made by technology designers and implementors thus have political implications that are often ignored. If these implications are not made a part of the design process, the resulting effects on society can be quite undesirable. The research advanced here therefore begins with a political decision: It is almost always a greater social good to protect personal information against unauthorized disclosure than it is to allow such disclosure. This decision is expressly in conflict with those of many businesses and government entities. Starting from this premise, a multi-agent architecture was designed that uses both strong cryptography and decentralization to enable a broad class of Internet-based software applications to handle personal information in a way that is highly resistant to disclosure. Further, the design is robust in ways that can enable users to trust it more easily: They can trust it to keep private information private, and they can trust that no single entity can take the system away from them. Thus, by starting with the explicit political goal of encouraging well-placed user trust, the research described here not only makes its social choices clear, it also demonstrates certain technical advantages over more traditional approaches. We discuss the political and technical background of this research, and explain what sorts of applications are enabled by the multi-agent architecture proposed. We then describe a representative example of this architecture--the Yenta matchmaking system. Yenta uses the coordinated interaction of large numbers of agents to form coalitions of users across the Internet who share common interests, and then enables both one-to-one and group conversations among them. It does so with a high degree of privacy, security, and robustness, without requiring its users to place unwarranted trust in any single point in the system.by Leonard Newton Foner.Ph.D

    WiFi Miner: An online apriori and sensor based wireless network Intrusion Detection System

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    This thesis proposes an Intrusion Detection System, WiFi Miner, which applies an infrequent pattern association rule mining Apriori technique to wireless network packets captured through hardware sensors for purposes of real time detection of intrusive or anomalous packets. Contributions of the proposed system includes effectively adapting an efficient data mining association rule technique to important problem of intrusion detection in a wireless network environment using hardware sensors, providing a solution that eliminates the need for hard-to-obtain training data in this environment, providing increased intrusion detection rate and reduction of false alarms. The proposed system, WiFi Miner, solution approach is to find frequent and infrequent patterns on pre-processed wireless connection records using infrequent pattern finding Apriori algorithm also proposed by this thesis. The proposed Online Apriori-Infrequent algorithm improves the join and prune step of the traditional Apriori algorithm with a rule that avoids joining itemsets not likely to produce frequent itemsets as their results, thereby improving efficiency and run times significantly. A positive anomaly score is assigned to each packet (record) for each infrequent pattern found while a negative anomaly score is assigned for each frequent pattern found. So, a record with final positive anomaly score is considered as anomaly based on the presence of more infrequent patterns than frequent patterns found

    Sixth Goddard Conference on Mass Storage Systems and Technologies Held in Cooperation with the Fifteenth IEEE Symposium on Mass Storage Systems

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    This document contains copies of those technical papers received in time for publication prior to the Sixth Goddard Conference on Mass Storage Systems and Technologies which is being held in cooperation with the Fifteenth IEEE Symposium on Mass Storage Systems at the University of Maryland-University College Inn and Conference Center March 23-26, 1998. As one of an ongoing series, this Conference continues to provide a forum for discussion of issues relevant to the management of large volumes of data. The Conference encourages all interested organizations to discuss long term mass storage requirements and experiences in fielding solutions. Emphasis is on current and future practical solutions addressing issues in data management, storage systems and media, data acquisition, long term retention of data, and data distribution. This year's discussion topics include architecture, tape optimization, new technology, performance, standards, site reports, vendor solutions. Tutorials will be available on shared file systems, file system backups, data mining, and the dynamics of obsolescence

    A User Centric Security Model for Tamper-Resistant Devices

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    In this thesis we propose a design for a ubiquitous and interoperable device based on the smart card architecture to meet the challenges of privacy, trust, and security for traditional and emerging technologies like personal computers, smart phones and tablets. Such a de- vice is referred a User Centric Tamper-Resistant Device (UCTD). To support the smart card architecture for the UCTD initiative, we propose the delegation of smart card owner- ship from a centralised authority (i.e. the card issuer) to users. This delegation mandated a review of existing smart card mechanisms and their proposals for modifications/improve- ments to their operation. Since the inception of smart card technology, the dominant ownership model in the smart card industry has been refer to as the Issuer Centric Smart Card Ownership Model (ICOM). The ICOM has no doubt played a pivotal role in the proliferation of the technology into various segments of modern life. However, it has been a barrier to the convergence of different services on a smart card. In addition, it might be considered as a hurdle to the adaption of smart card technology into a general-purpose security device. To avoid these issues, we propose citizen ownership of smart cards, referred as the User Centric Smart Card Ownership Model (UCOM). Contrary to the ICOM, it gives the power of decision to install or delete an application on a smart card to its user. The ownership of corresponding applications remains with their respective application providers along with the choice to lease their application to a card or not. In addition, based on the UCOM framework, we also proposed the Coopetitive Architecture for Smart Cards (CASC) that merges the centralised control of card issuers with the provision of application choice to the card user. In the core of the thesis, we analyse the suitability of the existing smart card architectures for the UCOM. This leads to the proposal of three major contributions spanning the smart card architecture, the application management framework, and the execution environment. Furthermore, we propose protocols for the application installation mechanism and the application sharing mechanism (i.e. smart card firewall). In addition to this, we propose a framework for backing-up, migrating, and restoring the smart card contents. Finally, we provide the test implementation results of the proposed protocols along with their performance measures. The protocols are then compared in terms of features and performance with existing smart cards and internet protocols. In order to provide a more detailed analysis of proposed protocols and for the sake of completeness, we performed mechanical formal analysis using the CasperFDR.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    An ad hoc wireless mobile communications model for Special Operations Forces

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    The digitization of the battlefield enables special operators to use improved communications supported by computer networks across a range of missions. The communications paradigm is evolving toward mobile wireless ad hoc networks. This development enables an autonomous system of mobile nodes supporting peer-to-peer communications in forward-deployed military networks. Ad hoc networks have to establish a reliable, secure, instant, and usually temporary, communication infrastructure and to be able to access in a global communications infrastructure. Our model describes a global communication network supporting the special operator in mobile wireless communications. The main purpose is to provide a handheld wireless communications node which is capable of transferring voice, data, and imagery to and from parallel and vertical command structures within an environment replete with electronic countermeasures. The model will support the representation of requirements such as throughput, quality of service with low power consumption, and low probability of detection/interception. Special Forces are moving toward using commercial-off-the- shelf products and services based on availability and cost effectiveness. Using GloMoSim tool, we run simulations for a direct action scenario and compared the efficiency of on-demand and table-driven routing protocols under different bandwidths and communications loadshttp://www.archive.org/details/adhocwirelessmob00ogutFirst Lieutenant, Turkish ArmyApproved for public release; distribution is unlimited
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