Adrian Dabrowski, N. Pianta, Thomas Klepp, M. Mulazzani, E. Weippl
IMSI Catchers are used in mobile networks to identify and eavesdrop on phones. When, the number of vendors increased and prices dropped, the device became available to much larger audiences. Self-made devices based on open source software are available for about US$ 1,500. In this paper, we identify and describe multiple methods of detecting artifacts in the mobile network produced by such devices. We present two independent novel implementations of an IMSI Catcher Catcher (ICC) to detect this threat against everyone's privacy. The first one employs a network of stationary (sICC) measurement units installed in a geographical area and constantly scanning all frequency bands for cell announcements and fingerprinting the cell network parameters. These rooftop-mounted devices can cover large areas. The second implementation is an app for standard consumer grade mobile phones (mICC), without the need to root or jailbreak them. Its core principle is based upon geographical network topology correlation, facilitating the ubiquitous built-in GPS receiver in today's phones and a network cell capabilities fingerprinting technique. The latter works for the vicinity of the phone by first learning the cell landscape and than matching it against the learned data. We implemented and evaluated both solutions for digital self-defense and deployed several of the stationary units for a long term field-test. Finally, we describe how to detect recently published denial of service attacks.
{"title":"IMSI-catch me if you can: IMSI-catcher-catchers","authors":"Adrian Dabrowski, N. Pianta, Thomas Klepp, M. Mulazzani, E. Weippl","doi":"10.1145/2664243.2664272","DOIUrl":"https://doi.org/10.1145/2664243.2664272","url":null,"abstract":"IMSI Catchers are used in mobile networks to identify and eavesdrop on phones. When, the number of vendors increased and prices dropped, the device became available to much larger audiences. Self-made devices based on open source software are available for about US$ 1,500. In this paper, we identify and describe multiple methods of detecting artifacts in the mobile network produced by such devices. We present two independent novel implementations of an IMSI Catcher Catcher (ICC) to detect this threat against everyone's privacy. The first one employs a network of stationary (sICC) measurement units installed in a geographical area and constantly scanning all frequency bands for cell announcements and fingerprinting the cell network parameters. These rooftop-mounted devices can cover large areas. The second implementation is an app for standard consumer grade mobile phones (mICC), without the need to root or jailbreak them. Its core principle is based upon geographical network topology correlation, facilitating the ubiquitous built-in GPS receiver in today's phones and a network cell capabilities fingerprinting technique. The latter works for the vicinity of the phone by first learning the cell landscape and than matching it against the learned data. We implemented and evaluated both solutions for digital self-defense and deployed several of the stationary units for a long term field-test. Finally, we describe how to detect recently published denial of service attacks.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133855860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AIS, Automatic Identification System, is an application of cyber-physical systems (CPS) to smart transportation at sea. Being primarily used for collision avoidance and traffic monitoring by ship captains and maritime authorities, AIS is a mandatory installation for over 300,000 vessels worldwide since 2002. Other promoted benefits are accident investigation, aids to navigation and search and rescue (SAR) operations. In this paper, we present a unique security evaluation of AIS, by introducing threats affecting both the implementation in online providers and the protocol specification. Using a novel software-based AIS transmitter that we designed, we show that our findings affect all transponders deployed globally on vessels and other maritime stations like lighthouses, buoys, AIS gateways, vessel traffic services and aircraft involved in SAR operations. Our concerns have been acknowledged by online providers and international standards organizations, and we are currently and actively working together to improve the overall security.
{"title":"A security evaluation of AIS automated identification system","authors":"Marco Balduzzi, A. Pasta, Kyle Wilhoit","doi":"10.1145/2664243.2664257","DOIUrl":"https://doi.org/10.1145/2664243.2664257","url":null,"abstract":"AIS, Automatic Identification System, is an application of cyber-physical systems (CPS) to smart transportation at sea. Being primarily used for collision avoidance and traffic monitoring by ship captains and maritime authorities, AIS is a mandatory installation for over 300,000 vessels worldwide since 2002. Other promoted benefits are accident investigation, aids to navigation and search and rescue (SAR) operations. In this paper, we present a unique security evaluation of AIS, by introducing threats affecting both the implementation in online providers and the protocol specification. Using a novel software-based AIS transmitter that we designed, we show that our findings affect all transponders deployed globally on vessels and other maritime stations like lighthouses, buoys, AIS gateways, vessel traffic services and aircraft involved in SAR operations. Our concerns have been acknowledged by online providers and international standards organizations, and we are currently and actively working together to improve the overall security.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114697657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Garbled circuits offer a powerful primitive for computation on a user's personal data while keeping that data private. Despite recent improvements, constructing and evaluating circuits of any useful size remains expensive on the limited hardware resources of a smartphone, the primary computational device available to most users around the world. In this work, we develop a new technique for securely outsourcing the generation of garbled circuits to a Cloud provider. By outsourcing the circuit generation, we are able to eliminate the most costly operations from the mobile device, including oblivious transfers. Our proofs of security show that this technique provides the best security guarantees of any existing garbled circuit outsourcing protocol. We also experimentally demonstrate that our new protocol, on average, decreases execution time by 75% and reduces network costs by 60% compared to previous outsourcing protocols. In so doing, we demonstrate that the use of garbled circuits on mobile devices can be made nearly as practical as it is becoming for server-class machines.
{"title":"Whitewash: outsourcing garbled circuit generation for mobile devices","authors":"Henry Carter, Chaz Lever, Patrick Traynor","doi":"10.1145/2664243.2664255","DOIUrl":"https://doi.org/10.1145/2664243.2664255","url":null,"abstract":"Garbled circuits offer a powerful primitive for computation on a user's personal data while keeping that data private. Despite recent improvements, constructing and evaluating circuits of any useful size remains expensive on the limited hardware resources of a smartphone, the primary computational device available to most users around the world. In this work, we develop a new technique for securely outsourcing the generation of garbled circuits to a Cloud provider. By outsourcing the circuit generation, we are able to eliminate the most costly operations from the mobile device, including oblivious transfers. Our proofs of security show that this technique provides the best security guarantees of any existing garbled circuit outsourcing protocol. We also experimentally demonstrate that our new protocol, on average, decreases execution time by 75% and reduces network costs by 60% compared to previous outsourcing protocols. In so doing, we demonstrate that the use of garbled circuits on mobile devices can be made nearly as practical as it is becoming for server-class machines.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131343931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Repackaged Android applications (or simply apps) are one of the major sources of mobile malware and also an important cause of severe revenue loss to app developers. Although a number of solutions have been proposed to detect repackaged apps, the majority of them heavily rely on code analysis, thus suffering from two limitations: (1) poor scalability due to the billion opcode problem; (2) unreliability to code obfuscation/app hardening techniques. In this paper, we explore an alternative approach that exploits core resources, which have close relationships with codes, to detect repackaged apps. More precisely, we define new features for characterizing apps, investigate two kinds of algorithms for searching similar apps, and propose a two-stage methodology to speed up the detection. We realize our approach in a system named ResDroid and conduct large scale evaluation on it. The results show that ResDroid can identify repackaged apps efficiently and effectively even if they are protected by obfuscation or hardening systems.
{"title":"Towards a scalable resource-driven approach for detecting repackaged Android applications","authors":"Yuru Shao, Xiapu Luo, Chenxiong Qian, Peng Fei Zhu, Lei Zhang","doi":"10.1145/2664243.2664275","DOIUrl":"https://doi.org/10.1145/2664243.2664275","url":null,"abstract":"Repackaged Android applications (or simply apps) are one of the major sources of mobile malware and also an important cause of severe revenue loss to app developers. Although a number of solutions have been proposed to detect repackaged apps, the majority of them heavily rely on code analysis, thus suffering from two limitations: (1) poor scalability due to the billion opcode problem; (2) unreliability to code obfuscation/app hardening techniques. In this paper, we explore an alternative approach that exploits core resources, which have close relationships with codes, to detect repackaged apps. More precisely, we define new features for characterizing apps, investigate two kinds of algorithms for searching similar apps, and propose a two-stage methodology to speed up the detection. We realize our approach in a system named ResDroid and conduct large scale evaluation on it. The results show that ResDroid can identify repackaged apps efficiently and effectively even if they are protected by obfuscation or hardening systems.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133706678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Barreto, A. Cárdenas, N. Quijano, E. Mojica-Nava
Demand response systems assume an electricity retail-market with strategic electricity consuming agents. The goal in these systems is to design load shaping mechanisms to achieve efficiency of resources and customer satisfaction. Recent research efforts have studied the impact of integrity attacks in simplified versions of the demand response problem, where neither the load consuming agents nor the adversary are strategic. In this paper, we study the impact of integrity attacks considering strategic players (a social planner or a consumer) and a strategic attacker. We identify two types of attackers: (1) a malicious attacker who wants to damage the equipment in the power grid by producing sudden overloads, and (2) a selfish attacker that wants to defraud the system by compromising and then manipulating control (load shaping) signals. We then explore the resiliency of two different demand response systems to these fraudsters and malicious attackers. Our results provide guidelines for system operators deciding which type of demand-response system they want to implement, how to secure them, and directions for detecting these attacks.
{"title":"CPS: market analysis of attacks against demand response in the smart grid","authors":"C. Barreto, A. Cárdenas, N. Quijano, E. Mojica-Nava","doi":"10.1145/2664243.2664284","DOIUrl":"https://doi.org/10.1145/2664243.2664284","url":null,"abstract":"Demand response systems assume an electricity retail-market with strategic electricity consuming agents. The goal in these systems is to design load shaping mechanisms to achieve efficiency of resources and customer satisfaction. Recent research efforts have studied the impact of integrity attacks in simplified versions of the demand response problem, where neither the load consuming agents nor the adversary are strategic. In this paper, we study the impact of integrity attacks considering strategic players (a social planner or a consumer) and a strategic attacker. We identify two types of attackers: (1) a malicious attacker who wants to damage the equipment in the power grid by producing sudden overloads, and (2) a selfish attacker that wants to defraud the system by compromising and then manipulating control (load shaping) signals. We then explore the resiliency of two different demand response systems to these fraudsters and malicious attackers. Our results provide guidelines for system operators deciding which type of demand-response system they want to implement, how to secure them, and directions for detecting these attacks.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130757261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Eigner, Matteo Maffei, I. Pryvalov, F. Pampaloni, Aniket Kate
Computing aggregate statistics about user data is of vital importance for a variety of services and systems, but this practice has been shown to seriously undermine the privacy of users. Differential privacy has proved to be an effective tool to sanitize queries over a database, and various cryptographic protocols have been recently proposed to enforce differential privacy in a distributed setting, e.g., statical queries on sensitive data stored on the user's side. The widespread deployment of differential privacy techniques in real-life settings is, however, undermined by several limitations that existing constructions suffer from: they support only a limited class of queries, they pose a trade-off between privacy and utility of the query result, they are affected by the answer pollution problem, or they are inefficient. This paper presents PrivaDA, a novel design architecture for distributed differential privacy that leverages recent advances in secure multiparty computations on fixed and floating point arithmetics to overcome the previously mentioned limitations. In particular, PrivaDA supports a variety of perturbation mechanisms (e.g., the Laplace, discrete Laplace, and exponential mechanisms) and it constitutes the first generic technique to generate noise in a fully distributed manner while maintaining the optimal utility. Furthermore, PrivaDA does not suffer from the answer pollution problem. We demonstrate the efficiency of PrivaDA with a performance evaluation, and its expressiveness and flexibility by illustrating several application scenarios such as privacy-preserving web analytics.
{"title":"Differentially private data aggregation with optimal utility","authors":"F. Eigner, Matteo Maffei, I. Pryvalov, F. Pampaloni, Aniket Kate","doi":"10.1145/2664243.2664263","DOIUrl":"https://doi.org/10.1145/2664243.2664263","url":null,"abstract":"Computing aggregate statistics about user data is of vital importance for a variety of services and systems, but this practice has been shown to seriously undermine the privacy of users. Differential privacy has proved to be an effective tool to sanitize queries over a database, and various cryptographic protocols have been recently proposed to enforce differential privacy in a distributed setting, e.g., statical queries on sensitive data stored on the user's side. The widespread deployment of differential privacy techniques in real-life settings is, however, undermined by several limitations that existing constructions suffer from: they support only a limited class of queries, they pose a trade-off between privacy and utility of the query result, they are affected by the answer pollution problem, or they are inefficient. This paper presents PrivaDA, a novel design architecture for distributed differential privacy that leverages recent advances in secure multiparty computations on fixed and floating point arithmetics to overcome the previously mentioned limitations. In particular, PrivaDA supports a variety of perturbation mechanisms (e.g., the Laplace, discrete Laplace, and exponential mechanisms) and it constitutes the first generic technique to generate noise in a fully distributed manner while maintaining the optimal utility. Furthermore, PrivaDA does not suffer from the answer pollution problem. We demonstrate the efficiency of PrivaDA with a performance evaluation, and its expressiveness and flexibility by illustrating several application scenarios such as privacy-preserving web analytics.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"412 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124400805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Data outsourcing offers cost-effective computing power to manage massive data streams and reliable access to data. Data owners can forward their data to clouds, and the clouds provide data mirroring, backup, and online access services to end users. However, outsourcing data to untrusted clouds requires data authenticity and query integrity to remain in the control of the data owners and users. In this paper, we address the authenticated data-outsourcing problem specifically for multi-version key-value data that is subject to continuous updates under the constraints of data integrity, data authenticity, and "freshness" (i.e., ensuring that the value returned for a key is the latest version). We detail this problem and propose IncBM-Tree, a novel construct delivering freshness and authenticity. Compared to existing work, we provide a solution that offers (i) lightweight signing and verification on massive data update streams for data owners and users (e.g., allowing for small memory footprint and CPU usage for a low-budget IT department), (ii) immediate authentication of data freshness, (iii) support of authentication in the presence of both real-time and historical data accesses. Extensive benchmark evaluations demonstrate that IncBM-Tree achieves higher throughput (in an order of magnitude) for data stream authentication than existing work. For data owners and end users that have limited computing power, IncBM-Tree can be a practical solution to authenticate the freshness of outsourced data while reaping the benefits of broadly available cloud services.
{"title":"Lightweight authentication of freshness in outsourced key-value stores","authors":"Y. Tang, Ting Wang, Ling Liu, Xin Hu, Jiyong Jang","doi":"10.1145/2664243.2664244","DOIUrl":"https://doi.org/10.1145/2664243.2664244","url":null,"abstract":"Data outsourcing offers cost-effective computing power to manage massive data streams and reliable access to data. Data owners can forward their data to clouds, and the clouds provide data mirroring, backup, and online access services to end users. However, outsourcing data to untrusted clouds requires data authenticity and query integrity to remain in the control of the data owners and users. In this paper, we address the authenticated data-outsourcing problem specifically for multi-version key-value data that is subject to continuous updates under the constraints of data integrity, data authenticity, and \"freshness\" (i.e., ensuring that the value returned for a key is the latest version). We detail this problem and propose IncBM-Tree, a novel construct delivering freshness and authenticity. Compared to existing work, we provide a solution that offers (i) lightweight signing and verification on massive data update streams for data owners and users (e.g., allowing for small memory footprint and CPU usage for a low-budget IT department), (ii) immediate authentication of data freshness, (iii) support of authentication in the presence of both real-time and historical data accesses. Extensive benchmark evaluations demonstrate that IncBM-Tree achieves higher throughput (in an order of magnitude) for data stream authentication than existing work. For data owners and end users that have limited computing power, IncBM-Tree can be a practical solution to authenticate the freshness of outsourced data while reaping the benefits of broadly available cloud services.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129051347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Side-channel attacks try to breach confidentiality and retrieve critical secrets through the side channels. Cache memories are a potential source of information leakage through side-channel attacks, many of which have been proposed. Meanwhile, different cache architectures have also been proposed to defend against these attacks. However, there are currently no means for comparing and evaluating the effectiveness of different defense solutions against these attacks. In this paper, we propose a novel method to evaluate a system's vulnerability to side-channel attacks. We establish side-channel leakage models based on the non-interference property. Then we define how the security aspects of a cache architecture can be modeled as a finite-state machine (FSM) with state transitions that cause interference. We use mutual information to quantitatively reveal potential side-channel leakage of the architectures, and allow comparison of these architectures for their relative vulnerabilities to side-channel attacks. We use real attacks to validate our results.
{"title":"New models of cache architectures characterizing information leakage from cache side channels","authors":"Tianwei Zhang, R. Lee","doi":"10.1145/2664243.2664273","DOIUrl":"https://doi.org/10.1145/2664243.2664273","url":null,"abstract":"Side-channel attacks try to breach confidentiality and retrieve critical secrets through the side channels. Cache memories are a potential source of information leakage through side-channel attacks, many of which have been proposed. Meanwhile, different cache architectures have also been proposed to defend against these attacks. However, there are currently no means for comparing and evaluating the effectiveness of different defense solutions against these attacks. In this paper, we propose a novel method to evaluate a system's vulnerability to side-channel attacks. We establish side-channel leakage models based on the non-interference property. Then we define how the security aspects of a cache architecture can be modeled as a finite-state machine (FSM) with state transitions that cause interference. We use mutual information to quantitatively reveal potential side-channel leakage of the architectures, and allow comparison of these architectures for their relative vulnerabilities to side-channel attacks. We use real attacks to validate our results.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"298 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122740385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tamara Denning, D. Kramer, Batya Friedman, M. Reynolds, Brian T. Gill, Tadayoshi Kohno
Wireless implantable medical devices (IMDs) are cyber-physical systems that deliver life-saving treatments to cardiac patients with dangerous heart conditions. Current access control models for these systems are insufficient; more security is necessary. In response to this problem, the technical security community has investigated new directions for improving security on these resource-constrained devices. Defenses, however, must not only be technically secure; in order to be deployable, defenses must be designed to work within the needs and constraints of their relevant application spaces. Designing for an application space---particularly a specialized one---requires a deep understanding of the stakeholders, their values, and the contexts of technology usage. Grounding our work in value sensitive design (VSD), we collaborated as an interdisciplinary team to conduct three workshops with medical providers for the purpose of gathering their values and perspectives. The structure of our workshop builds on known workshop structures within the human-computer interaction (HCI) community, and the number of participants in our workshops (N=24) is compatible with current practices for inductive, exploratory studies. We present results on: what the participants find important with respect to providing care and performing their jobs; their reactions to potential security system concepts; and their views on what security system properties should be sought or avoided due to side effects within the context of their work practice. We synthesize these results, use the results to articulate design considerations for future technical security systems, and suggest directions for further research. Our research not only provides a contribution to security research for an important class of cyber-physical systems (IMDs); it also provides an example of leveraging techniques from other communities to better explore the landscape of security designs for technologies.
{"title":"CPS: beyond usability: applying value sensitive design based methods to investigate domain characteristics for security for implantable cardiac devices","authors":"Tamara Denning, D. Kramer, Batya Friedman, M. Reynolds, Brian T. Gill, Tadayoshi Kohno","doi":"10.1145/2664243.2664289","DOIUrl":"https://doi.org/10.1145/2664243.2664289","url":null,"abstract":"Wireless implantable medical devices (IMDs) are cyber-physical systems that deliver life-saving treatments to cardiac patients with dangerous heart conditions. Current access control models for these systems are insufficient; more security is necessary. In response to this problem, the technical security community has investigated new directions for improving security on these resource-constrained devices. Defenses, however, must not only be technically secure; in order to be deployable, defenses must be designed to work within the needs and constraints of their relevant application spaces. Designing for an application space---particularly a specialized one---requires a deep understanding of the stakeholders, their values, and the contexts of technology usage. Grounding our work in value sensitive design (VSD), we collaborated as an interdisciplinary team to conduct three workshops with medical providers for the purpose of gathering their values and perspectives. The structure of our workshop builds on known workshop structures within the human-computer interaction (HCI) community, and the number of participants in our workshops (N=24) is compatible with current practices for inductive, exploratory studies. We present results on: what the participants find important with respect to providing care and performing their jobs; their reactions to potential security system concepts; and their views on what security system properties should be sought or avoided due to side effects within the context of their work practice. We synthesize these results, use the results to articulate design considerations for future technical security systems, and suggest directions for further research. Our research not only provides a contribution to security research for an important class of cyber-physical systems (IMDs); it also provides an example of leveraging techniques from other communities to better explore the landscape of security designs for technologies.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117070016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With over forty years of use and refinement, access control, often in the form of access control rules (ACRs), continues to be a significant control mechanism for information security. However, ACRs are typically either buried within existing natural language (NL) artifacts or elicited from subject matter experts. To address the first situation, our research goal is to aid developers who implement ACRs by inferring ACRs from NL artifacts. To aid in rule inference, we propose an approach that extracts relations (i.e., the relationship among two or more items) from NL artifacts such as requirements documents. Unlike existing approaches, our approach combines techniques from information extraction and machine learning. We develop an iterative algorithm to discover patterns that represent ACRs in sentences. We seed this algorithm with frequently occurring nouns matching a subject--action--resource pattern throughout a document. The algorithm then searches for additional combinations of those nouns to discover additional patterns. We evaluate our approach on documents from three systems in three domains: conference management, education, and healthcare. Our evaluation results show that ACRs exist in 47% of the sentences, and our approach effectively identifies those ACR sentences with a precision of 81% and recall of 65%; our approach extracts ACRs from those identified ACR sentences with an average precision of 76% and an average recall of 49%.
{"title":"Relation extraction for inferring access control rules from natural language artifacts","authors":"John Slankas, Xusheng Xiao, L. Williams, Tao Xie","doi":"10.1145/2664243.2664280","DOIUrl":"https://doi.org/10.1145/2664243.2664280","url":null,"abstract":"With over forty years of use and refinement, access control, often in the form of access control rules (ACRs), continues to be a significant control mechanism for information security. However, ACRs are typically either buried within existing natural language (NL) artifacts or elicited from subject matter experts. To address the first situation, our research goal is to aid developers who implement ACRs by inferring ACRs from NL artifacts. To aid in rule inference, we propose an approach that extracts relations (i.e., the relationship among two or more items) from NL artifacts such as requirements documents. Unlike existing approaches, our approach combines techniques from information extraction and machine learning. We develop an iterative algorithm to discover patterns that represent ACRs in sentences. We seed this algorithm with frequently occurring nouns matching a subject--action--resource pattern throughout a document. The algorithm then searches for additional combinations of those nouns to discover additional patterns. We evaluate our approach on documents from three systems in three domains: conference management, education, and healthcare. Our evaluation results show that ACRs exist in 47% of the sentences, and our approach effectively identifies those ACR sentences with a precision of 81% and recall of 65%; our approach extracts ACRs from those identified ACR sentences with an average precision of 76% and an average recall of 49%.","PeriodicalId":104443,"journal":{"name":"Proceedings of the 30th Annual Computer Security Applications Conference","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114696568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}