Visible to the public Biblio

Found 9603 results

2014-09-17
Denning, Dorothy E..  1976.  A Lattice Model of Secure Information Flow. Commun. ACM. 19:236–243.
This paper investigates mechanisms that guarantee secure information flow in a computer system. These mechanisms are examined within a mathematical framework suitable for formulating the requirements of secure information flow among security classes. The central component of the model is a lattice structure derived from the security classes and justified by the semantics of information flow. The lattice properties permit concise formulations of the security requirements of different existing systems and facilitate the construction of mechanisms that enforce security. The model provides a unifying view of all systems that restrict information flow, enables a classification of them according to security objectives, and suggests some new approaches. It also leads to the construction of automatic program certification mechanisms for verifying the secure flow of information through a program.
Lampson, Butler W..  1974.  Protection. SIGOPS Oper. Syst. Rev.. 8:18–24.

Abstract models are given which reflect the properties of most existing mechanisms for enforcing protection or access control, together with some possible implementations. The properties of existing systems are explicated in terms of the model and implementations.

This article was identified by the SoS Best Scientific Cybersecurity Paper Competition Distinguished Experts as a Science of Security Significant Paper. The Science of Security Paper Competition was developed to recognize and honor recently published papers that advance the science of cybersecurity. During the development of the competition, members of the Distinguished Experts group suggested that listing papers that made outstanding contributions, empirical or theoretical, to the science of cybersecurity in earlier years would also benefit the research community.

Schneider, Fred B..  2000.  Enforceable Security Policies. ACM Trans. Inf. Syst. Secur.. 3:30–50.
A precise characterization is given for the class of security policies enforceable with mechanisms that work by monitoring system execution, and automata are introduced for specifying exactly that class of security policies. Techniques to enforce security policies specified by such automata are also discussed.
Thompson, Ken.  1984.  Reflections on Trusting Trust. Commun. ACM. 27:761–763.
To what extent should one trust a statement that a program is free of Trojan horses? Perhaps it is more important to trust the people who wrote the software.
Williams, Laurie A., Nicol, David M., Singh, Munindar P..  2014.  HotSoS '14: Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. Symposium and Bootcamp on the Science of Security.

The Symposium and Bootcamp on the Science of Security (HotSoS), is a research event centered on the Science of Security (SoS). Following a successful invitational SoS Community Meeting in December 2012, HotSoS 2014 was the first open research event in what we expect will be a continuing series of such events. The key motivation behind developing a Science of Security is to address the fundamental problems of cybersecurity in a principled manner. Security has been intensively studied, but a lot of previous research emphasizes the engineering of specific solutions without first developing the scientific understanding of the problem domain. All too often, security research conveys the flavor of identifying specific threats and removing them in an apparently ad hoc manner. The motivation behind the nascent Science of Security is to understand how computing systems are architected, built, used, and maintained with a view to understanding and addressing security challenges systematically across their life cycle. In particular, two features distinguish the Science of Security from previous research programs on cybersecurity. Scope. The Science of Security considers not just computational artifacts but also incorporates the human, social, and organizational aspects of computing within its purview. Approach. The Science of Security takes a decidedly scientific approach, based on the understanding of empirical evaluation and theoretical foundations as developed in the natural and social sciences, but adapted as appropriate for the "artificial science" (paraphrasing Herb Simon's term) that is computing.

Maass, Michael, Scherlis, William L., Aldrich, Jonathan.  2014.  In-nimbo Sandboxing. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :1:1–1:12.

Sandboxes impose a security policy, isolating applications and their components from the rest of a system. While many sandboxing techniques exist, state of the art sandboxes generally perform their functions within the system that is being defended. As a result, when the sandbox fails or is bypassed, the security of the surrounding system can no longer be assured. We experiment with the idea of in-nimbo sandboxing, encapsulating untrusted computations away from the system we are trying to protect. The idea is to delegate computations that may be vulnerable or malicious to virtual machine instances in a cloud computing environment. This may not reduce the possibility of an in-situ sandbox compromise, but it could significantly reduce the consequences should that possibility be realized. To achieve this advantage, there are additional requirements, including: (1) A regulated channel between the local and cloud environments that supports interaction with the encapsulated application, (2) Performance design that acceptably minimizes latencies in excess of the in-situ baseline. To test the feasibility of the idea, we built an in-nimbo sandbox for Adobe Reader, an application that historically has been subject to significant attacks. We undertook a prototype deployment with PDF users in a large aerospace firm. In addition to thwarting several examples of existing PDF-based malware, we found that the added increment of latency, perhaps surprisingly, does not overly impair the user experience with respect to performance or usability.

Schmerl, Bradley, Cámara, Javier, Gennari, Jeffrey, Garlan, David, Casanova, Paulo, Moreno, Gabriel A., Glazier, Thomas J., Barnes, Jeffrey M..  2014.  Architecture-based Self-protection: Composing and Reasoning About Denial-of-service Mitigations. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :2:1–2:12.

Security features are often hardwired into software applications, making it difficult to adapt security responses to reflect changes in runtime context and new attacks. In prior work, we proposed the idea of architecture-based self-protection as a way of separating adaptation logic from application logic and providing a global perspective for reasoning about security adaptations in the context of other business goals. In this paper, we present an approach, based on this idea, for combating denial-of-service (DoS) attacks. Our approach allows DoS-related tactics to be composed into more sophisticated mitigation strategies that encapsulate possible responses to a security problem. Then, utility-based reasoning can be used to consider different business contexts and qualities. We describe how this approach forms the underpinnings of a scientific approach to self-protection, allowing us to reason about how to make the best choice of mitigation at runtime. Moreover, we also show how formal analysis can be used to determine whether the mitigations cover the range of conditions the system is likely to encounter, and the effect of mitigations on other quality attributes of the system. We evaluate the approach using the Rainbow self-adaptive framework and show how Rainbow chooses DoS mitigation tactics that are sensitive to different business contexts.

Escobar, Santiago, Meadows, Catherine, Meseguer, José, Santiago, Sonia.  2014.  A Rewriting-based Forwards Semantics for Maude-NPA. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :3:1–3:12.

The Maude-NRL Protocol Analyzer (Maude-NPA) is a tool for reasoning about the security of cryptographic protocols in which the cryptosystems satisfy different equational properties. It tries to find secrecy or authentication attacks by searching backwards from an insecure attack state pattern that may contain logical variables, in such a way that logical variables become properly instantiated in order to find an initial state. The execution mechanism for this logical reachability is narrowing modulo an equational theory. Although Maude-NPA also possesses a forwards semantics naturally derivable from the backwards semantics, it is not suitable for state space exploration or protocol simulation. In this paper we define an executable forwards semantics for Maude-NPA, instead of its usual backwards one, and restrict it to the case of concrete states, that is, to terms without logical variables. This case corresponds to standard rewriting modulo an equational theory. We prove soundness and completeness of the backwards narrowing-based semantics with respect to the rewriting-based forwards semantics. We show its effectiveness as an analysis method that complements the backwards analysis with new prototyping, simulation, and explicit-state model checking features by providing some experimental results.

Feigenbaum, Joan, Jaggard, Aaron D., Wright, Rebecca N..  2014.  Open vs. Closed Systems for Accountability. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :4:1–4:11.

The relationship between accountability and identity in online life presents many interesting questions. Here, we first systematically survey the various (directed) relationships among principals, system identities (nyms) used by principals, and actions carried out by principals using those nyms. We also map these relationships to corresponding accountability-related properties from the literature. Because punishment is fundamental to accountability, we then focus on the relationship between punishment and the strength of the connection between principals and nyms. To study this particular relationship, we formulate a utility-theoretic framework that distinguishes between principals and the identities they may use to commit violations. In doing so, we argue that the analogue applicable to our setting of the well known concept of quasilinear utility is insufficiently rich to capture important properties such as reputation. We propose more general utilities with linear transfer that do seem suitable for this model. In our use of this framework, we define notions of "open" and "closed" systems. This distinction captures the degree to which system participants are required to be bound to their system identities as a condition of participating in the system. This allows us to study the relationship between the strength of identity binding and the accountability properties of a system.

King, Jason, Williams, Laurie.  2014.  Log Your CRUD: Design Principles for Software Logging Mechanisms. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :5:1–5:10.

According to a 2011 survey in healthcare, the most commonly reported breaches of protected health information involved employees snooping into medical records of friends and relatives. Logging mechanisms can provide a means for forensic analysis of user activity in software systems by proving that a user performed certain actions in the system. However, logging mechanisms often inconsistently capture user interactions with sensitive data, creating gaps in traces of user activity. Explicit design principles and systematic testing of logging mechanisms within the software development lifecycle may help strengthen the overall security of software. The objective of this research is to observe the current state of logging mechanisms by performing an exploratory case study in which we systematically evaluate logging mechanisms by supplementing the expected results of existing functional black-box test cases to include log output. We perform an exploratory case study of four open-source electronic health record (EHR) logging mechanisms: OpenEMR, OSCAR, Tolven eCHR, and WorldVistA. We supplement the expected results of 30 United States government-sanctioned test cases to include log output to track access of sensitive data. We then execute the test cases on each EHR system. Six of the 30 (20%) test cases failed on all four EHR systems because user interactions with sensitive data are not logged. We find that viewing protected data is often not logged by default, allowing unauthorized views of data to go undetected. Based on our results, we propose a set of principles that developers should consider when developing logging mechanisms to ensure the ability to capture adequate traces of user activity.

Da, Gaofeng, Xu, Maochao, Xu, Shouhuai.  2014.  A New Approach to Modeling and Analyzing Security of Networked Systems. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :6:1–6:12.

Modeling and analyzing security of networked systems is an important problem in the emerging Science of Security and has been under active investigation. In this paper, we propose a new approach towards tackling the problem. Our approach is inspired by the shock model and random environment techniques in the Theory of Reliability, while accommodating security ingredients. To the best of our knowledge, our model is the first that can accommodate a certain degree of adaptiveness of attacks, which substantially weakens the often-made independence and exponential attack inter-arrival time assumptions. The approach leads to a stochastic process model with two security metrics, and we attain some analytic results in terms of the security metrics.

Rao, Ashwini, Hibshi, Hanan, Breaux, Travis, Lehker, Jean-Michel, Niu, Jianwei.  2014.  Less is More?: Investigating the Role of Examples in Security Studies Using Analogical Transfer Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :7:1–7:12.

Information system developers and administrators often overlook critical security requirements and best practices. This may be due to lack of tools and techniques that allow practitioners to tailor security knowledge to their particular context. In order to explore the impact of new security methods, we must improve our ability to study the impact of security tools and methods on software and system development. In this paper, we present early findings of an experiment to assess the extent to which the number and type of examples used in security training stimuli can impact security problem solving. To motivate this research, we formulate hypotheses from analogical transfer theory in psychology. The independent variables include number of problem surfaces and schemas, and the dependent variable is the answer accuracy. Our study results do not show a statistically significant difference in performance when the number and types of examples are varied. We discuss the limitations, threats to validity and opportunities for future studies in this area.

Tembe, Rucha, Zielinska, Olga, Liu, Yuqi, Hong, Kyung Wha, Murphy-Hill, Emerson, Mayhorn, Chris, Ge, Xi.  2014.  Phishing in International Waters: Exploring Cross-national Differences in Phishing Conceptualizations Between Chinese, Indian and American Samples. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :8:1–8:7.

One hundred-sixty four participants from the United States, India and China completed a survey designed to assess past phishing experiences and whether they engaged in certain online safety practices (e.g., reading a privacy policy). The study investigated participants' reported agreement regarding the characteristics of phishing attacks, types of media where phishing occurs and the consequences of phishing. A multivariate analysis of covariance indicated that there were significant differences in agreement regarding phishing characteristics, phishing consequences and types of media where phishing occurs for these three nationalities. Chronological age and education did not influence the agreement ratings; therefore, the samples were demographically equivalent with regards to these variables. A logistic regression analysis was conducted to analyze the categorical variables and nationality data. Results based on self-report data indicated that (1) Indians were more likely to be phished than Americans, (2) Americans took protective actions more frequently than Indians by destroying old documents, and (3) Americans were more likely to notice the "padlock" security icon than either Indian or Chinese respondents. The potential implications of these results are discussed in terms of designing culturally sensitive anti-phishing solutions.

Layman, Lucas, Diffo, Sylvain David, Zazworka, Nico.  2014.  Human Factors in Webserver Log File Analysis: A Controlled Experiment on Investigating Malicious Activity. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :9:1–9:11.

While automated methods are the first line of defense for detecting attacks on webservers, a human agent is required to understand the attacker's intent and the attack process. The goal of this research is to understand the value of various log fields and the cognitive processes by which log information is grouped, searched, and correlated. Such knowledge will enable the development of human-focused log file investigation technologies. We performed controlled experiments with 65 subjects (IT professionals and novices) who investigated excerpts from six webserver log files. Quantitative and qualitative data were gathered to: 1) analyze subject accuracy in identifying malicious activity; 2) identify the most useful pieces of log file information; and 3) understand the techniques and strategies used by subjects to process the information. Statistically significant effects were observed in the accuracy of identifying attacks and time taken depending on the type of attack. Systematic differences were also observed in the log fields used by high-performing and low-performing groups. The findings include: 1) new insights into how specific log data fields are used to effectively assess potentially malicious activity; 2) obfuscating factors in log data from a human cognitive perspective; and 3) practical implications for tools to support log file investigations.

Han, Yujuan, Lu, Wenlian, Xu, Shouhuai.  2014.  Characterizing the Power of Moving Target Defense via Cyber Epidemic Dynamics. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :10:1–10:12.

Moving Target Defense (MTD) can enhance the resilience of cyber systems against attacks. Although there have been many MTD techniques, there is no systematic understanding and quantitative characterization of the power of MTD. In this paper, we propose to use a cyber epidemic dynamics approach to characterize the power of MTD. We define and investigate two complementary measures that are applicable when the defender aims to deploy MTD to achieve a certain security goal. One measure emphasizes the maximum portion of time during which the system can afford to stay in an undesired configuration (or posture), without considering the cost of deploying MTD. The other measure emphasizes the minimum cost of deploying MTD, while accommodating that the system has to stay in an undesired configuration (or posture) for a given portion of time. Our analytic studies lead to algorithms for optimally deploying MTD.

Das, Anupam, Borisov, Nikita, Caesar, Matthew.  2014.  Analyzing an Adaptive Reputation Metric for Anonymity Systems. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :11:1–11:11.

Low-latency anonymity systems such as Tor rely on intermediate relays to forward user traffic; these relays, however, are often unreliable, resulting in a degraded user experience. Worse yet, malicious relays may introduce deliberate failures in a strategic manner in order to increase their chance of compromising anonymity. In this paper we propose using a reputation metric that can profile the reliability of relays in an anonymity system based on users' past experience. The two main challenges in building a reputation-based system for an anonymity system are: first, malicious participants can strategically oscillate between good and malicious nature to evade detection, and second, an observed failure in an anonymous communication cannot be uniquely attributed to a single relay. Our proposed framework addresses the former challenge by using a proportional-integral-derivative (PID) controller-based reputation metric that ensures malicious relays adopting time-varying strategic behavior obtain low reputation scores over time, and the latter by introducing a filtering scheme based on the evaluated reputation score to effectively discard relays mounting attacks. We collect data from the live Tor network and perform simulations to validate the proposed reputation-based filtering scheme. We show that an attacker does not gain any significant benefit by performing deliberate failures in the presence of the proposed reputation framework.

Mitra, Sayan.  2014.  Proving Abstractions of Dynamical Systems Through Numerical Simulations. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :12:1–12:9.

A key question that arises in rigorous analysis of cyberphysical systems under attack involves establishing whether or not the attacked system deviates significantly from the ideal allowed behavior. This is the problem of deciding whether or not the ideal system is an abstraction of the attacked system. A quantitative variation of this question can capture how much the attacked system deviates from the ideal. Thus, algorithms for deciding abstraction relations can help measure the effect of attacks on cyberphysical systems and to develop attack detection strategies. In this paper, we present a decision procedure for proving that one nonlinear dynamical system is a quantitative abstraction of another. Directly computing the reach sets of these nonlinear systems are undecidable in general and reach set over-approximations do not give a direct way for proving abstraction. Our procedure uses (possibly inaccurate) numerical simulations and a model annotation to compute tight approximations of the observable behaviors of the system and then uses these approximations to decide on abstraction. We show that the procedure is sound and that it is guaranteed to terminate under reasonable robustness assumptions.

Xu, Shouhuai.  2014.  Emergent Behavior in Cybersecurity. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :13:1–13:2.

We argue that emergent behavior is inherent to cybersecurity.

Xu, Shouhuai.  2014.  Cybersecurity Dynamics. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :14:1–14:2.

We explore the emerging field of Cybersecurity Dynamics, a candidate foundation for the Science of Cybersecurity.

Layman, Lucas, Zazworka, Nico.  2014.  InViz: Instant Visualization of Security Attacks. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :15:1–15:2.

The InViz tool is a functional prototype that provides graphical visualizations of log file events to support real-time attack investigation. Through visualization, both experts and novices in cybersecurity can analyze patterns of application behavior and investigate potential cybersecurity attacks. The goal of this research is to identify and evaluate the cybersecurity information to visualize that reduces the amount of time required to perform cyber forensics.

Ray, Arnab, Cleaveland, Rance.  2014.  An Analysis Method for Medical Device Security. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :16:1–16:2.

This paper is a proposal for a poster. In it we describe a medical device security approach that researchers at Fraunhofer used to analyze different kinds of medical devices for security vulnerabilities. These medical devices were provided to Fraunhofer by a medical device manufacturer whose name we cannot disclose due to non-disclosure agreements.

Huang, Jingwei, Nicol, David M..  2014.  Evidence-based Trust Reasoning. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :17:1–17:2.

Trust is a necessary component in cybersecurity. It is a common task for a system to make a decision about whether or not to trust the credential of an entity from another domain, issued by a third party. Generally, in the cyberspace, connected and interacting systems largely rely on each other with respect to security, privacy, and performance. In their interactions, one entity or system needs to trust others, and this "trust" frequently becomes a vulnerability of that system. Aiming at mitigating the vulnerability, we are developing a computational theory of trust, as a part of our efforts towards Science of Security. Previously, we developed a formal-semantics-based calculus of trust [3, 2], in which trust can be calculated based on a trustor's direct observation on the performance of the trustee, or based on a trust network. In this paper, we construct a framework for making trust reasoning based on the observed evidence. We take privacy in cloud computing as a driving application case [5].

Kurilova, Darya, Omar, Cyrus, Nistor, Ligia, Chung, Benjamin, Potanin, Alex, Aldrich, Jonathan.  2014.  Type-specific Languages to Fight Injection Attacks. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :18:1–18:2.

Injection vulnerabilities have topped rankings of the most critical web application vulnerabilities for several years [1, 2]. They can occur anywhere where user input may be erroneously executed as code. The injected input is typically aimed at gaining unauthorized access to the system or to private information within it, corrupting the system's data, or disturbing system availability. Injection vulnerabilities are tedious and difficult to prevent.

Biswas, Trisha, Lesser, Kendra, Dutta, Rudra, Oishi, Meeko.  2014.  Examining Reliability of Wireless Multihop Network Routing with Linear Systems. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :19:1–19:2.

In this study, we present a control theoretic technique to model routing in wireless multihop networks. We model ad hoc wireless networks as stochastic dynamical systems where, as a base case, a centralized controller pre-computes optimal paths to the destination. The usefulness of this approach lies in the fact that it can help obtain bounds on reliability of end-to-end packet transmissions. We compare this approach with the reliability achieved by some of the widely used routing techniques in multihop networks.

Ibrahim, Naseem.  2014.  Trustworthy Context-dependent Services. Proceedings of the 2014 Symposium and Bootcamp on the Science of Security. :20:1–20:2.

With the wide popularity of Cloud Computing, Service-oriented Computing is becoming the de-facto approach for the development of distributed systems. This has introduced the issue of trustworthiness with respect to the services being provided. Service Requesters are provided with a wide range of services that they can select from. Usually the service requester compare between these services according to their cost and quality. One essential part of the quality of a service is the trustworthiness properties of such services. Traditional service models focuses on service functionalities and cost when defining services. This paper introduces a new service model that extends traditional service models to support trustworthiness properties.