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CANTINA+: A Feature-Rich Machine Learning Framework for Detecting Phishing Web Sites CANTINA+:一个功能丰富的机器学习框架,用于检测钓鱼网站
Q Engineering Pub Date : 2011-09-01 DOI: 10.1145/2019599.2019606
Guang Xiang, Jason I. Hong, C. Rosé, L. Cranor
Phishing is a plague in cyberspace. Typically, phish detection methods either use human-verified URL blacklists or exploit Web page features via machine learning techniques. However, the former is frail in terms of new phish, and the latter suffers from the scarcity of effective features and the high false positive rate (FP). To alleviate those problems, we propose a layered anti-phishing solution that aims at (1) exploiting the expressiveness of a rich set of features with machine learning to achieve a high true positive rate (TP) on novel phish, and (2) limiting the FP to a low level via filtering algorithms. Specifically, we proposed CANTINA+, the most comprehensive feature-based approach in the literature including eight novel features, which exploits the HTML Document Object Model (DOM), search engines and third party services with machine learning techniques to detect phish. Moreover, we designed two filters to help reduce FP and achieve runtime speedup. The first is a near-duplicate phish detector that uses hashing to catch highly similar phish. The second is a login form filter, which directly classifies Web pages with no identified login form as legitimate. We extensively evaluated CANTINA+ with two methods on a diverse spectrum of corpora with 8118 phish and 4883 legitimate Web pages. In the randomized evaluation, CANTINA+ achieved over 92% TP on unique testing phish and over 99% TP on near-duplicate testing phish, and about 0.4% FP with 10% training phish. In the time-based evaluation, CANTINA+ also achieved over 92% TP on unique testing phish, over 99% TP on near-duplicate testing phish, and about 1.4% FP under 20% training phish with a two-week sliding window. Capable of achieving 0.4% FP and over 92% TP, our CANTINA+ has been demonstrated to be a competitive anti-phishing solution.
网络钓鱼是网络空间的瘟疫。通常,网络钓鱼检测方法要么使用人工验证的URL黑名单,要么通过机器学习技术利用Web页面特征。然而,前者在新的网络钓鱼方面很脆弱,而后者则存在有效特征缺乏和假阳性率(FP)高的问题。为了缓解这些问题,我们提出了一种分层的反网络钓鱼解决方案,旨在(1)利用机器学习的丰富特征集的表现力来实现对新型网络钓鱼的高真阳性率(TP),以及(2)通过过滤算法将FP限制在较低的水平。具体来说,我们提出了CANTINA+,这是文献中最全面的基于特征的方法,包括八个新特征,它利用HTML文档对象模型(DOM)、搜索引擎和第三方服务以及机器学习技术来检测网络钓鱼。此外,我们设计了两个过滤器来帮助减少FP并实现运行时加速。第一种是近重复网络钓鱼检测器,它使用散列来捕获高度相似的网络钓鱼。第二个是登录表单过滤器,它直接将没有标识的登录表单的Web页面分类为合法的。我们用两种方法在不同的语料库上对CANTINA+进行了广泛的评估,其中包含8118个钓鱼网站和4883个合法网页。在随机评估中,CANTINA+对唯一测试网络钓鱼的TP值超过92%,对近重复测试网络钓鱼的TP值超过99%,对10%的训练网络钓鱼的TP值约为0.4%。在基于时间的评估中,CANTINA+在唯一测试网络钓鱼上也达到了92%以上的TP,在近重复测试网络钓鱼上达到了99%以上的TP,在两周的滑动窗口下,在20%的训练网络钓鱼下达到了1.4%的FP。能够达到0.4%的FP和超过92%的TP,我们的CANTINA+已被证明是一个有竞争力的反网络钓鱼解决方案。
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引用次数: 480
Security Seals on Voting Machines: A Case Study 投票机上的安全封条:一个案例研究
Q Engineering Pub Date : 2011-09-01 DOI: 10.1145/2019599.2019603
A. Appel
Tamper-evident seals are used by many states’ election officials on voting machines and ballot boxes, either to protect the computer and software from fraudulent modification or to protect paper ballots from fraudulent substitution or stuffing. Physical tamper-indicating seals can usually be easily defeated, given they way they are typically made and used; and the effectiveness of seals depends on the protocol for their application and inspection. The legitimacy of our elections may therefore depend on whether a particular state’s use of seals is effective to prevent, deter, or detect election fraud. This paper is a case study of the use of seals on voting machines by the State of New Jersey. I conclude that New Jersey’s protocols for the use of tamper-evident seals have been not at all effective. I conclude with a discussion of the more general problem of seals in democratic elections.
许多州的选举官员在投票机和投票箱上使用防篡改封条,以保护计算机和软件不受欺诈性修改,或保护纸质选票不受欺诈性替换或填充。物理防篡改指示封条通常很容易被破解,因为它们通常是用这种方式制造和使用的;印章的有效性取决于其应用和检查的协议。因此,我们选举的合法性可能取决于某个州是否有效地使用印章来防止、阻止或发现选举欺诈。本文是新泽西州在投票机上使用印章的案例研究。我的结论是,新泽西关于使用防篡改封条的协议一点都不有效。最后,我将讨论民主选举中更为普遍的封印问题。
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引用次数: 21
Checksum-Aware Fuzzing Combined with Dynamic Taint Analysis and Symbolic Execution 结合动态污点分析和符号执行的校验和感知模糊检测
Q Engineering Pub Date : 2011-09-01 DOI: 10.1145/2019599.2019600
Tielei Wang, Tao Wei, G. Gu, Wei Zou
Fuzz testing has proven successful in finding security vulnerabilities in large programs. However, traditional fuzz testing tools have a well-known common drawback: they are ineffective if most generated inputs are rejected at the early stage of program running, especially when target programs employ checksum mechanisms to verify the integrity of inputs. This article presents TaintScope, an automatic fuzzing system using dynamic taint analysis and symbolic execution techniques, to tackle the above problem. TaintScope has several novel features: (1) TaintScope is a checksum-aware fuzzing tool. It can identify checksum fields in inputs, accurately locate checksum-based integrity checks by using branch profiling techniques, and bypass such checks via control flow alteration. Furthermore, it can fix checksum values in generated inputs using combined concrete and symbolic execution techniques. (2) TaintScope is a taint-based fuzzing tool working at the x86 binary level. Based on fine-grained dynamic taint tracing, TaintScope identifies the “hot bytes” in a well-formed input that are used in security-sensitive operations (e.g., invoking system/library calls), and then focuses on modifying such bytes with random or boundary values. (3) TaintScope is also a symbolic-execution-based fuzzing tool. It can symbolically evaluate a trace, reason about all possible values that can execute the trace, and then detect potential vulnerabilities on the trace. We evaluate TaintScope on a number of large real-world applications. Experimental results show that TaintScope can accurately locate the checksum checks in programs and dramatically improve the effectiveness of fuzz testing. TaintScope has already found 30 previously unknown vulnerabilities in several widely used applications, including Adobe Acrobat, Flash Player, Google Picasa, and Microsoft Paint. Most of these severe vulnerabilities have been confirmed by Secunia and oCERT, and assigned CVE identifiers (such as CVE-2009-1882, CVE-2009-2688). Vendor patches have been released or are in preparation based on our reports.
模糊测试在发现大型程序中的安全漏洞方面已经被证明是成功的。然而,传统的模糊测试工具有一个众所周知的共同缺点:如果大多数生成的输入在程序运行的早期阶段被拒绝,特别是当目标程序使用校验和机制来验证输入的完整性时,它们是无效的。本文介绍了一种采用动态污点分析和符号执行技术的自动模糊测试系统TaintScope来解决上述问题。TaintScope有几个新颖的特性:(1)TaintScope是一个校验和感知模糊测试工具。它可以识别输入中的校验和字段,通过使用分支分析技术准确定位基于校验和的完整性检查,并通过控制流更改绕过此类检查。此外,它可以使用组合的具体执行和符号执行技术来固定生成输入中的校验和值。(2) TaintScope是一个基于污染的模糊测试工具,工作在x86二进制级别。基于细粒度动态跟踪,TaintScope识别格式良好的输入中用于安全敏感操作(例如,调用系统/库调用)的“热字节”,然后专注于用随机值或边界值修改这些字节。(3) TaintScope也是一个基于符号执行的模糊测试工具。它可以象征性地评估跟踪,推断可以执行跟踪的所有可能值,然后检测跟踪上的潜在漏洞。我们在许多大型实际应用中评估了TaintScope。实验结果表明,TaintScope能够准确定位程序中的校验和检查,显著提高了模糊测试的有效性。TaintScope已经在几个广泛使用的应用程序(包括Adobe Acrobat、Flash Player、Google Picasa和Microsoft Paint)中发现了30个以前未知的漏洞。这些严重漏洞中的大多数已经被Secunia和oCERT确认,并分配了CVE标识符(如CVE-2009-1882, CVE-2009-2688)。根据我们的报告,供应商补丁已经发布或正在准备中。
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引用次数: 41
Formal Reasoning about Physical Properties of Security Protocols 安全协议物理特性的形式化推理
Q Engineering Pub Date : 2011-09-01 DOI: 10.1145/2019599.2019601
D. Basin, Srdjan Capkun, P. Schaller, Benedikt Schmidt
Traditional security protocols are mainly concerned with authentication and key establishment and rely on predistributed keys and properties of cryptographic operators. In contrast, new application areas are emerging that establish and rely on properties of the physical world. Examples include protocols for secure localization, distance bounding, and secure time synchronization. We present a formal model for modeling and reasoning about such physical security protocols. Our model extends standard, inductive, trace-based, symbolic approaches with a formalization of physical properties of the environment, namely communication, location, and time. In particular, communication is subject to physical constraints, for example, message transmission takes time determined by the communication medium used and the distance between nodes. All agents, including intruders, are subject to these constraints and this results in a distributed intruder with restricted, but more realistic, communication capabilities than those of the standard Dolev-Yao intruder. We have formalized our model in Isabelle/HOL and have used it to verify protocols for authenticated ranging, distance bounding, broadcast authentication based on delayed key disclosure, and time synchronization.
传统的安全协议主要关注认证和密钥建立,依赖于预分布密钥和密码算子的属性。相比之下,新的应用领域正在兴起,这些领域建立并依赖于物理世界的特性。示例包括安全定位、距离边界和安全时间同步协议。我们提出了一个形式化模型,用于对此类物理安全协议进行建模和推理。我们的模型扩展了标准的、归纳的、基于痕迹的、符号的方法,将环境的物理属性(即通信、位置和时间)形式化。特别是,通信受到物理条件的限制,例如,消息的传输需要的时间取决于所使用的通信介质和节点之间的距离。包括入侵者在内的所有代理都受到这些约束,这导致分布式入侵者的通信能力比标准的Dolev-Yao入侵者受限,但更现实。我们已经在Isabelle/HOL中形式化了我们的模型,并使用它来验证身份验证测距、距离边界、基于延迟密钥披露的广播身份验证和时间同步的协议。
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引用次数: 48
Introduction to special section SACMAT'08 介绍特别部分SACMAT'08
Q Engineering Pub Date : 2011-06-06 DOI: 10.1145/1952982.1952983
Ninghui Li
This issue of TISSEC includes extended versions of articles selected from the program of the 13th ACM Symposium on Access Control Models and Technologies (SACMAT 2008), which took place from June 11 to 13, 2008 in Estes Park, CO. SACMAT is a successful series of symposiums that continue the tradition, first established by the ACM Workshop on Role-Based Access Control, of being the premier forum for the presentation of research results and experience reports on leading-edge issues of access control, including models, systems, applications, and theory. The missions of the symposium are to share novel access control solutions that fulfill the needs of heterogeneous applications and environments and to identify new directions for future research and development. SACMAT gives researchers and practitioners a unique opportunity to share their perspectives with others interested in the various aspects of access control. The articles in this special issue were invited for submission from the 20 articles presented at SACMAT 2008. These were selected from 79 submissions from authors in 24 countries in Africa, Asia, Australia, Europe, North America, and South America. All the journal submissions went through an additional thorough review process to further ensure their quality. The first article “Detecting and Resolving Policy Misconfigurations in Access-Control Systems” by Lujo Bauer, Scott Garriss, and Michael K. Reiter applies association rule mining to the history of accesses to predict changes to access-control policies that are likely to be consistent with users’ intention, so that these changes can be instituted in advance of misconfigurations interfering with legitimate accesses. As instituting these changes requires the consent of the appropriate administrator, the article also introduces techniques to automatically determine from whom to seek consent and to minimize the costs of doing so. The proposed techniques are evaluated using data from a deployed access-control system. The second article “Authorization Recycling in Hierarchical RBAC Systems” by Qiang Wei, Jason Crampton, Konstantin Beznosov, and Matei Ripeanu introduces and evaluates the mechanisms for authorization “recycling” in RBAC enterprise systems. These mechanisms cache and reuse previous authorization decisions to help address the problem that the policy decision point in distributed applications tends to become a single point of failure and a performance bottleneck. The algorithms that support these mechanisms allow making precise and approximate authorization decisions, thereby masking possible failures of the authorization server and reducing its load. I would like to thank all the authors for submitting their research results in this special issue and to all the reviewers for their insightful comments. I am also grateful to Gene Tsudik, editor-in-chief, for his guidance and help throughout this process.
本期TISSEC包括从第13届ACM访问控制模型和技术研讨会(SACMAT 2008)计划中选择的文章的扩展版本,该研讨会于2008年6月11日至13日在CO. Estes Park举行。SACMAT是一个成功的系列研讨会,延续了传统,首先由ACM基于角色的访问控制研讨会建立。作为展示访问控制前沿问题的研究成果和经验报告的主要论坛,包括模型,系统,应用和理论。研讨会的任务是分享满足异构应用和环境需求的新颖访问控制解决方案,并确定未来研究和发展的新方向。SACMAT为研究人员和从业人员提供了一个独特的机会,与对访问控制的各个方面感兴趣的其他人分享他们的观点。这期特刊的文章被邀请从SACMAT 2008上发表的20篇文章中提交。这些作品是从来自非洲、亚洲、澳大利亚、欧洲、北美和南美24个国家的79位作者提交的作品中挑选出来的。所有提交的期刊都经过了额外的彻底审查过程,以进一步确保其质量。由Lujo Bauer、Scott Garriss和Michael K. Reiter撰写的第一篇文章“在访问控制系统中检测和解决策略错误配置”将关联规则挖掘应用于访问历史,以预测可能与用户意图一致的访问控制策略的更改,以便在错误配置干扰合法访问之前制定这些更改。由于实施这些更改需要适当的管理员的同意,因此本文还介绍了自动确定从谁那里寻求同意并将这样做的成本降至最低的技术。使用部署的访问控制系统的数据对所提出的技术进行了评估。Qiang Wei、Jason Crampton、Konstantin Beznosov和Matei Ripeanu撰写的第二篇文章“分层RBAC系统中的授权回收”介绍并评估了RBAC企业系统中的授权“回收”机制。这些机制缓存和重用以前的授权决策,以帮助解决分布式应用程序中的策略决策点容易成为单点故障和性能瓶颈的问题。支持这些机制的算法允许做出精确和近似的授权决策,从而掩盖授权服务器可能出现的故障并减少其负载。感谢所有作者在本期特刊中提交的研究成果,感谢所有审稿人的精辟评论。我还要感谢主编Gene Tsudik在整个过程中的指导和帮助。
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引用次数: 88
False data injection attacks against state estimation in electric power grids 针对电网状态估计的虚假数据注入攻击
Q Engineering Pub Date : 2011-05-01 DOI: 10.1145/1952982.1952995
Yao Liu, P. Ning, M. Reiter
A power grid is a complex system connecting electric power generators to consumers through power transmission and distribution networks across a large geographical area. System monitoring is necessary to ensure the reliable operation of power grids, and state estimation is used in system monitoring to best estimate the power grid state through analysis of meter measurements and power system models. Various techniques have been developed to detect and identify bad measurements, including interacting bad measurements introduced by arbitrary, nonrandom causes. At first glance, it seems that these techniques can also defeat malicious measurements injected by attackers. In this article, we expose an unknown vulnerability of existing bad measurement detection algorithms by presenting and analyzing a new class of attacks, called false data injection attacks, against state estimation in electric power grids. Under the assumption that the attacker can access the current power system configuration information and manipulate the measurements of meters at physically protected locations such as substations, such attacks can introduce arbitrary errors into certain state variables without being detected by existing algorithms. Moreover, we look at two scenarios, where the attacker is either constrained to specific meters or limited in the resources required to compromise meters. We show that the attacker can systematically and efficiently construct attack vectors in both scenarios to change the results of state estimation in arbitrary ways. We also extend these attacks to generalized false data injection attacks, which can further increase the impact by exploiting measurement errors typically tolerated in state estimation. We demonstrate the success of these attacks through simulation using IEEE test systems, and also discuss the practicality of these attacks and the real-world constraints that limit their effectiveness.
电网是一个复杂的系统,通过横跨大地理区域的输电和配电网络将发电机与消费者连接起来。系统监测是保证电网可靠运行的必要条件,在系统监测中使用状态估计,通过对电表测量和电力系统模型的分析,对电网状态进行最佳估计。已经开发了各种技术来检测和识别不良测量,包括由任意、非随机原因引入的交互不良测量。乍一看,这些技术似乎也可以挫败攻击者注入的恶意度量。在本文中,我们通过提出和分析针对电网状态估计的一类新的攻击(称为虚假数据注入攻击),暴露了现有不良测量检测算法的未知漏洞。假设攻击者可以访问当前的电力系统配置信息并操纵变电站等物理保护位置的仪表测量,这种攻击可以在现有算法无法检测到的情况下为某些状态变量引入任意误差。此外,我们还研究了两种场景,其中攻击者要么被限制在特定的仪表上,要么被限制在破坏仪表所需的资源上。研究表明,在这两种情况下,攻击者都可以系统有效地构造攻击向量,以任意方式改变状态估计的结果。我们还将这些攻击扩展到广义的虚假数据注入攻击,通过利用通常在状态估计中可以容忍的测量误差,可以进一步增加影响。我们通过使用IEEE测试系统的模拟演示了这些攻击的成功,并讨论了这些攻击的实用性和限制其有效性的现实世界约束。
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引用次数: 1058
Robust and efficient authentication of video stream broadcasting 视频流广播鲁棒高效认证
Q Engineering Pub Date : 2011-05-01 DOI: 10.1145/1952982.1952987
G. Oligeri, S. Chessa, R. D. Pietro, G. Giunta
We present a novel video stream authentication scheme which combines signature amortization by means of hash chains and an advanced watermarking technique. We propose a new hash chain construction, the Duplex Hash Chain, which allows us to achieve bit-by-bit authentication that is robust to low bit error rates. This construction is well suited for wireless broadcast communications characterized by low packet losses such as in satellite networks. Moreover, neither hardware upgrades nor specific end-user equipment are needed to enjoy the authentication services. The computation overhead experienced on the receiver only sums to two hashes per block of pictures and one digital signature verification for the whole received stream. This overhead introduces a provably negligible decrease in video quality. A thorough analysis of the proposed solution is provided in conjunction with extensive simulations.
提出了一种新的视频流认证方案,该方案结合了基于哈希链的签名摊销和先进的水印技术。我们提出了一种新的哈希链结构,即双工哈希链,它允许我们实现对低误码率具有鲁棒性的比特认证。这种结构非常适合无线广播通信的特点是低数据包丢失,如在卫星网络。此外,享受身份验证服务既不需要硬件升级,也不需要特定的终端用户设备。接收方经历的计算开销仅为每个图片块的两个哈希值和整个接收流的一个数字签名验证。这种开销导致的视频质量下降可以忽略不计。结合广泛的仿真,对所提出的解决方案进行了全面的分析。
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引用次数: 7
Remote data checking using provable data possession 使用可证明的数据所有权进行远程数据检查
Q Engineering Pub Date : 2011-05-01 DOI: 10.1145/1952982.1952994
G. Ateniese, R. Burns, Reza Curtmola, Joseph Herring, O. Khan, Lea Kissner, Zachary N. J. Peterson, D. Song
We introduce a model for provable data possession (PDP) that can be used for remote data checking: A client that has stored data at an untrusted server can verify that the server possesses the original data without retrieving it. The model generates probabilistic proofs of possession by sampling random sets of blocks from the server, which drastically reduces I/O costs. The client maintains a constant amount of metadata to verify the proof. The challenge/response protocol transmits a small, constant amount of data, which minimizes network communication. Thus, the PDP model for remote data checking is lightweight and supports large data sets in distributed storage systems. The model is also robust in that it incorporates mechanisms for mitigating arbitrary amounts of data corruption. We present two provably-secure PDP schemes that are more efficient than previous solutions. In particular, the overhead at the server is low (or even constant), as opposed to linear in the size of the data. We then propose a generic transformation that adds robustness to any remote data checking scheme based on spot checking. Experiments using our implementation verify the practicality of PDP and reveal that the performance of PDP is bounded by disk I/O and not by cryptographic computation. Finally, we conduct an in-depth experimental evaluation to study the tradeoffs in performance, security, and space overheads when adding robustness to a remote data checking scheme.
我们引入了一个可证明的数据占有(PDP)模型,该模型可用于远程数据检查:将数据存储在不受信任的服务器上的客户机可以验证服务器是否拥有原始数据,而无需检索原始数据。该模型通过从服务器中随机采样块集来生成占有的概率证明,这大大降低了I/O成本。客户端维护一定数量的元数据来验证证明。质询/响应协议传输少量恒定的数据,从而最大限度地减少网络通信。因此,用于远程数据检查的PDP模型是轻量级的,并且支持分布式存储系统中的大型数据集。该模型还具有健壮性,因为它包含了减轻任意数量数据损坏的机制。我们提出了两个可证明安全的PDP方案,它们比以前的解决方案更有效。特别是,服务器上的开销很低(甚至是恒定的),而不是数据大小呈线性变化。然后,我们提出了一种通用转换,该转换为基于抽查的任何远程数据检查方案增加了鲁棒性。实验验证了PDP的实用性,并表明PDP的性能受磁盘I/O的限制,而不受加密计算的限制。最后,我们进行了深入的实验评估,以研究在向远程数据检查方案添加鲁棒性时在性能、安全性和空间开销方面的权衡。
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引用次数: 420
Lightweight RFID authentication with forward and backward security 具有前向和后向安全性的轻量级RFID认证
Q Engineering Pub Date : 2011-05-01 DOI: 10.1145/1952982.1952993
M. Burmester, J. Munilla
We propose a lightweight RFID authentication protocol that supports forward and backward security. The only cryptographic mechanism that this protocol uses is a pseudorandom number generator (PRNG) that is shared with the backend Server. Authentication is achieved by exchanging a few numbers (3 or 5) drawn from the PRNG. The lookup time is constant, and the protocol can be easily adapted to prevent online man-in-the-middle relay attacks. Security is proven in the UC security framework.
我们提出了一种支持前向和后向安全的轻量级RFID认证协议。该协议使用的唯一加密机制是与后端服务器共享的伪随机数生成器(PRNG)。身份验证是通过交换从PRNG中提取的几个数字(3或5)来实现的。查找时间是恒定的,并且该协议可以很容易地用于防止在线中间人中继攻击。安全性在UC安全框架中得到验证。
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引用次数: 47
Detecting and resolving policy misconfigurations in access-control systems 检测和解决访问控制系统中的策略错误配置
Q Engineering Pub Date : 2011-05-01 DOI: 10.1145/1952982.1952984
Lujo Bauer, Scott Garriss, M. Reiter
Access-control policy misconfigurations that cause requests to be erroneously denied can result in wasted time, user frustration, and, in the context of particular applications (e.g., health care), very severe consequences. In this article we apply association rule mining to the history of accesses to predict changes to access-control policies that are likely to be consistent with users' intentions, so that these changes can be instituted in advance of misconfigurations interfering with legitimate accesses. Instituting these changes requires the consent of the appropriate administrator, of course, and so a primary contribution of our work is how to automatically determine from whom to seek consent and how to minimize the costs of doing so. We show using data from a deployed access-control system that our methods can reduce the number of accesses that would have incurred costly time-of-access delays by 43%, and can correctly predict 58% of the intended policy. These gains are achieved without impacting the total amount of time users spend interacting with the system.
访问控制策略配置错误会导致请求被错误地拒绝,这会导致浪费时间、用户受挫,并且在特定应用程序的上下文中(例如,医疗保健)会导致非常严重的后果。在本文中,我们将关联规则挖掘应用于访问历史,以预测可能与用户意图一致的访问控制策略的更改,以便在错误配置干扰合法访问之前制定这些更改。当然,实施这些更改需要适当的管理员的同意,因此我们工作的一个主要贡献是如何自动确定从谁那里寻求同意以及如何将这样做的成本降至最低。我们使用来自部署的访问控制系统的数据表明,我们的方法可以将会导致昂贵的访问时间延迟的访问次数减少43%,并且可以正确预测58%的预期策略。在不影响用户与系统交互的总时间的情况下实现这些增益。
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引用次数: 47
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ACM Transactions on Information and System Security
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