Causality analysis on system auditing data has emerged as an important solution for attack investigation. Given a POI (Point-Of-Interest) event (e.g., an alert fired on a suspicious file creation), causality analysis constructs a dependency graph, in which nodes represent system entities (e.g., processes and files) and edges represent dependencies among entities, to reveal the attack sequence. However, causality analysis often produces a huge graph (> 100,000 edges) that is hard for security analysts to inspect. From the dependency graphs of various attacks, we observe that (1) dependencies that are highly related to the POI event often exhibit a different set of properties (e.g., data flow and time) from the lessrelevant dependencies; (2) the POI event is often related to a few attack entries (e.g., downloading a file). Based on these insights, we propose DEPIMPACT, a framework that identifies the critical component of a dependency graph (i.e., a subgraph) by (1) assigning discriminative dependency weights to edges to distinguish critical edges that represent the attack sequence from less-important dependencies, (2) propagating dependency impacts backward from the POI event to entry points, and (3) performing forward causality analysis from the top-ranked entry nodes based on their dependency impacts to filter out edges that are not found in the forward causality analysis. Our evaluations on the 150 million real system auditing events of real attacks and the DARPA TC dataset show that DEPIMPACT can significantly reduce the large dependency graphs (∼ 1,000,000 edges) to a small graph (∼ 234 edges), which is 4611× smaller. The comparison with the other state-of-the-art causality analysis techniques shows that DEPIMPACT is 106× more effective in reducing the dependency graphs while preserving the attack sequences.
{"title":"Back-Propagating System Dependency Impact for Attack Investigation","authors":"Pengcheng Fang, Peng Gao, Changlin Liu, Erman Ayday, Kangkook Jee, Ting Wang, Yanfang Ye, Zhuotao Liu, Xusheng Xiao","doi":"10.5281/ZENODO.5559214","DOIUrl":"https://doi.org/10.5281/ZENODO.5559214","url":null,"abstract":"Causality analysis on system auditing data has emerged as an important solution for attack investigation. Given a POI (Point-Of-Interest) event (e.g., an alert fired on a suspicious file creation), causality analysis constructs a dependency graph, in which nodes represent system entities (e.g., processes and files) and edges represent dependencies among entities, to reveal the attack sequence. However, causality analysis often produces a huge graph (> 100,000 edges) that is hard for security analysts to inspect. From the dependency graphs of various attacks, we observe that (1) dependencies that are highly related to the POI event often exhibit a different set of properties (e.g., data flow and time) from the lessrelevant dependencies; (2) the POI event is often related to a few attack entries (e.g., downloading a file). Based on these insights, we propose DEPIMPACT, a framework that identifies the critical component of a dependency graph (i.e., a subgraph) by (1) assigning discriminative dependency weights to edges to distinguish critical edges that represent the attack sequence from less-important dependencies, (2) propagating dependency impacts backward from the POI event to entry points, and (3) performing forward causality analysis from the top-ranked entry nodes based on their dependency impacts to filter out edges that are not found in the forward causality analysis. Our evaluations on the 150 million real system auditing events of real attacks and the DARPA TC dataset show that DEPIMPACT can significantly reduce the large dependency graphs (∼ 1,000,000 edges) to a small graph (∼ 234 edges), which is 4611× smaller. The comparison with the other state-of-the-art causality analysis techniques shows that DEPIMPACT is 106× more effective in reducing the dependency graphs while preserving the attack sequences.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"32 1","pages":"2461-2478"},"PeriodicalIF":0.0,"publicationDate":"2021-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74996953","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}
Soo-Jin Moon, Yucheng Yin, R. Sharma, Yifei Yuan, Jonathan M. Spring, V. Sekar
Many recent DDoS attacks rely on amplification, where an attacker induces public servers to generate a large volume of network traffic to a victim. In this paper, we argue for a low-footprint Internet health monitoring service that can systematically and continuously quantify this risk to inform mitigation efforts. Unfortunately, the problem is challenging because amplification is a complex function of query (header) values and server instances. As such, existing techniques that enumerate the total number of servers or focus on a specific amplification-inducing query are fundamentally imprecise. In designing AmpMap, we leverage key structural insights to develop an efficient approach that searches across the space of protocol headers and servers. Using AmpMap, we scanned thousands of servers for 6 UDP-based protocols. We find that relying on prior recommendations to block or rate-limit specific queries still leaves open substantial residual risk as they miss many other amplification-inducing query patterns. We also observe significant variability across servers and protocols, and thus prior approaches that rely on server census can substantially misestimate amplification risk.
{"title":"Accurately Measuring Global Risk of Amplification Attacks using AmpMap","authors":"Soo-Jin Moon, Yucheng Yin, R. Sharma, Yifei Yuan, Jonathan M. Spring, V. Sekar","doi":"10.1184/R1/16709587.V1","DOIUrl":"https://doi.org/10.1184/R1/16709587.V1","url":null,"abstract":"Many recent DDoS attacks rely on amplification, where an attacker induces public servers to generate a large volume of network traffic to a victim. In this paper, we argue for a low-footprint Internet health monitoring service that can systematically and continuously quantify this risk to inform mitigation efforts. Unfortunately, the problem is challenging because amplification is a complex function of query (header) values and server instances. As such, existing techniques that enumerate the total number of servers or focus on a specific amplification-inducing query are fundamentally imprecise. In designing AmpMap, we leverage key structural insights to develop an efficient approach that searches across the space of protocol headers and servers. Using AmpMap, we scanned thousands of servers for 6 UDP-based protocols. We find that relying on prior recommendations to block or rate-limit specific queries still leaves open substantial residual risk as they miss many other amplification-inducing query patterns. We also observe significant variability across servers and protocols, and thus prior approaches that rely on server census can substantially misestimate amplification risk.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"17 1","pages":"3881-3898"},"PeriodicalIF":0.0,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79217890","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}
Small businesses (SBs) are often ill-informed and underresourced against increasing online threats. Chief Information Security Officers (CISOs) have a key role in contextualizing trade-offs between competing costs and priorities for SB management. To explore the challenges CISOs face when guiding SBs towards improved security we conducted two interview studies. Firstly, an exploratory study with CISOs with SB experience to identify themes related to their work (n=8). Secondly, we refined our methods and conducted broader structured interviews with a larger non-overlapping group of similarly qualified SB CISOs (n=19) to validate those themes and extend outcomes. We found CISOs confirmed common observations that SBs are generally unprepared for online threats, and uninformed about issues such as insurance and regulation. We also found that despite perceived usability problems with language and formatting, the effectiveness of government-authored guidance (a key reference source for CISOs and SBs) was deemed on par with commercial resources. These observations yield recommendations for better formatting, prioritizing, and timing of security guidance for SBs, such as better tailoring checklists, investment suggestions, and scenario-based exercises.
{"title":"Security Obstacles and Motivations for Small Businesses from a CISO's Perspective","authors":"Flynn Wolf, Adam J. Aviv, Ravi Kuber","doi":"10.13016/M2RCS6-O3WQ","DOIUrl":"https://doi.org/10.13016/M2RCS6-O3WQ","url":null,"abstract":"Small businesses (SBs) are often ill-informed and underresourced against increasing online threats. Chief Information Security Officers (CISOs) have a key role in contextualizing trade-offs between competing costs and priorities for SB management. To explore the challenges CISOs face when guiding SBs towards improved security we conducted two interview studies. Firstly, an exploratory study with CISOs with SB experience to identify themes related to their work (n=8). Secondly, we refined our methods and conducted broader structured interviews with a larger non-overlapping group of similarly qualified SB CISOs (n=19) to validate those themes and extend outcomes. We found CISOs confirmed common observations that SBs are generally unprepared for online threats, and uninformed about issues such as insurance and regulation. We also found that despite perceived usability problems with language and formatting, the effectiveness of government-authored guidance (a key reference source for CISOs and SBs) was deemed on par with commercial resources. These observations yield recommendations for better formatting, prioritizing, and timing of security guidance for SBs, such as better tailoring checklists, investment suggestions, and scenario-based exercises.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"76 1","pages":"1199-1216"},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85748374","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}
Pub Date : 2020-08-12DOI: 10.3929/ETHZ-B-000448132
Guillaume Girol, L. Hirschi, R. Sasse, Dennis Jackson, C. Cremers, D. Basin
The Noise specification describes how to systematically construct a large family of Diffie-Hellman based key exchange protocols, including the secure transports used by WhatsApp, Lightning, and WireGuard. As the specification only makes informal security claims, earlier work has explored which formal security properties may be enjoyed by protocols in the Noise framework, yet many important questions remain open. In this work we provide the most comprehensive, systematic analysis of the Noise framework to date. We start from first principles and, using an automated analysis tool, compute the strongest threat model under which a protocol is secure, thus enabling formal comparison between protocols. Our results allow us to objectively and automatically associate each informal security level presented in the Noise specification with a formal security claim. We also provide a fine-grained separation of Noise protocols that were previously described as offering similar security properties, revealing a subclass for which alternative Noise protocols exist that offer strictly better security guarantees. Our analysis also uncovers missing assumptions in the Noise specification and some surprising consequences, e.g., in some situations higher security levels yield strictly worse security.
{"title":"A Spectral Analysis of Noise: A Comprehensive, Automated, Formal Analysis of Diffie-Hellman Protocols","authors":"Guillaume Girol, L. Hirschi, R. Sasse, Dennis Jackson, C. Cremers, D. Basin","doi":"10.3929/ETHZ-B-000448132","DOIUrl":"https://doi.org/10.3929/ETHZ-B-000448132","url":null,"abstract":"The Noise specification describes how to systematically construct a large family of Diffie-Hellman based key exchange protocols, including the secure transports used by WhatsApp, Lightning, and WireGuard. As the specification only makes informal security claims, earlier work has explored which formal security properties may be enjoyed by protocols in the Noise framework, yet many important questions remain open. In this work we provide the most comprehensive, systematic analysis of the Noise framework to date. We start from first principles and, using an automated analysis tool, compute the strongest threat model under which a protocol is secure, thus enabling formal comparison between protocols. Our results allow us to objectively and automatically associate each informal security level presented in the Noise specification with a formal security claim. We also provide a fine-grained separation of Noise protocols that were previously described as offering similar security properties, revealing a subclass for which alternative Noise protocols exist that offer strictly better security guarantees. Our analysis also uncovers missing assumptions in the Noise specification and some surprising consequences, e.g., in some situations higher security levels yield strictly worse security.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"51 1","pages":"1857-1874"},"PeriodicalIF":0.0,"publicationDate":"2020-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72689687","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}
Pub Date : 2020-08-12DOI: 10.3929/ETHZ-B-000443480
Hossein Shafagh, Lukas Burkhalter, S. Ratnasamy, Anwar Hithnawi
This paper presents Droplet, a decentralized data access control service. Droplet enables data owners to securely and selectively share their encrypted data while guaranteeing data confidentiality in the presence of unauthorized parties and compromised data servers. Droplet’s contribution lies in coupling two key ideas: (i) a cryptographically-enforced access control construction for encrypted data streams which enables users to define fine-grained stream-specific access policies, and (ii) a decentralized authorization service that serves userdefined access policies. In this paper, we present Droplet’s design, the reference implementation of Droplet, and the experimental results of three case-study applications deployed with Droplet: Fitbit activity tracker, Ava health tracker, and ECOviz smart meter dashboard, demonstrating Droplet’s applicability for secure sharing of IoT streams.
{"title":"Droplet: Decentralized Authorization and Access Control for Encrypted Data Streams","authors":"Hossein Shafagh, Lukas Burkhalter, S. Ratnasamy, Anwar Hithnawi","doi":"10.3929/ETHZ-B-000443480","DOIUrl":"https://doi.org/10.3929/ETHZ-B-000443480","url":null,"abstract":"This paper presents Droplet, a decentralized data access control service. Droplet enables data owners to securely and selectively share their encrypted data while guaranteeing data confidentiality in the presence of unauthorized parties and compromised data servers. Droplet’s contribution lies in coupling two key ideas: (i) a cryptographically-enforced access control construction for encrypted data streams which enables users to define fine-grained stream-specific access policies, and (ii) a decentralized authorization service that serves userdefined access policies. In this paper, we present Droplet’s design, the reference implementation of Droplet, and the experimental results of three case-study applications deployed with Droplet: Fitbit activity tracker, Ava health tracker, and ECOviz smart meter dashboard, demonstrating Droplet’s applicability for secure sharing of IoT streams.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"10 1","pages":"2469-2486"},"PeriodicalIF":0.0,"publicationDate":"2020-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75527115","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}
. Ad-blocking applications have become increasingly popular among Internet users. Ad-blockers offer various privacy- and security-enhancing features: they can reduce personal data collection and exposure to malicious advertising, help safeguard users' decision-making autonomy, reduce users' costs (by increasing the speed of page loading), and improve the browsing experience (by reducing visual clutter). On the other hand, the online advertising industry has claimed that ads increase consumers' economic welfare by helping them find better, cheaper deals faster. If so, using ad-blockers would deprive consumers of these benefits. However, little is known about the actual economic impact of ad-blockers. We designed a lab experiment (N=212) with real economic incentives to understand the impact of ad-blockers on consumers' product searching and purchasing behavior, and the resulting consumer outcomes. We focus on the effects of blocking contextual ads (ads targeted to individual, potentially sensitive, contexts, such as search queries in a search engine or the content of web pages) on how participants searched for and purchased various products online, and the resulting consumer welfare. We find that blocking contextual ads did not have a statistically significant effect on the prices of products participants chose to purchase, the time they spent searching for them, or how satisfied they were with the chosen products, prices, and perceived quality. Hence we do not reject the null hypothesis that consumer behavior and outcomes stay constant when such ads are blocked or shown. We conclude that the use of ad-blockers does not seem to compromise consumer economic welfare (along the metrics captured in the experiment) in exchange for privacy and security benefits. We discuss the implications of this work in terms of end-users' privacy, the study's limitations, and future work to extend these results.Presented at the 29th USENIX Security Symposium, August 12-14, 2020
{"title":"The Impact of Ad-Blockers on Product Search and Purchase Behavior: A Lab Experiment","authors":"Alisa Frik, A. Haviland, A. Acquisti","doi":"10.1184/R1/13653134.V1","DOIUrl":"https://doi.org/10.1184/R1/13653134.V1","url":null,"abstract":". Ad-blocking applications have become increasingly popular among Internet users. Ad-blockers offer various privacy- and security-enhancing features: they can reduce personal data collection and exposure to malicious advertising, help safeguard users' decision-making autonomy, reduce users' costs (by increasing the speed of page loading), and improve the browsing experience (by reducing visual clutter). On the other hand, the online advertising industry has claimed that ads increase consumers' economic welfare by helping them find better, cheaper deals faster. If so, using ad-blockers would deprive consumers of these benefits. However, little is known about the actual economic impact of ad-blockers. We designed a lab experiment (N=212) with real economic incentives to understand the impact of ad-blockers on consumers' product searching and purchasing behavior, and the resulting consumer outcomes. We focus on the effects of blocking contextual ads (ads targeted to individual, potentially sensitive, contexts, such as search queries in a search engine or the content of web pages) on how participants searched for and purchased various products online, and the resulting consumer welfare. We find that blocking contextual ads did not have a statistically significant effect on the prices of products participants chose to purchase, the time they spent searching for them, or how satisfied they were with the chosen products, prices, and perceived quality. Hence we do not reject the null hypothesis that consumer behavior and outcomes stay constant when such ads are blocked or shown. We conclude that the use of ad-blockers does not seem to compromise consumer economic welfare (along the metrics captured in the experiment) in exchange for privacy and security benefits. We discuss the implications of this work in terms of end-users' privacy, the study's limitations, and future work to extend these results.Presented at the 29th USENIX Security Symposium, August 12-14, 2020","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"9 1","pages":"163-179"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88386276","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}
While pump-and-dump schemes have attracted the attention of cryptocurrency observers and regulators alike, this paper represents the first detailed empirical query of pump-and-dump activities in cryptocurrency markets. We present a case study of a recent pump-and-dump event, investigate 412 pump-and-dump activities organized in Telegram channels from June 17, 2018 to February 26, 2019, and discover patterns in crypto-markets associated with pump-and-dump schemes. We then build a model that predicts the pump likelihood of all coins listed in a crypto-exchange prior to a pump. The model exhibits high precision as well as robustness, and can be used to create a simple, yet very effective trading strategy, which we empirically demonstrate can generate a return as high as 60% on small retail investments within a span of two and half months. The study provides a proof of concept for strategic crypto-trading and sheds light on the application of machine learning for crime detection.
{"title":"The Anatomy of a Cryptocurrency Pump-and-Dump Scheme","authors":"Jiahua Xu, B. Livshits","doi":"10.5555/3361338.3361450","DOIUrl":"https://doi.org/10.5555/3361338.3361450","url":null,"abstract":"While pump-and-dump schemes have attracted the attention of cryptocurrency observers and regulators alike, this paper represents the first detailed empirical query of pump-and-dump activities in cryptocurrency markets. We present a case study of a recent pump-and-dump event, investigate 412 pump-and-dump activities organized in Telegram channels from June 17, 2018 to February 26, 2019, and discover patterns in crypto-markets associated with pump-and-dump schemes. We then build a model that predicts the pump likelihood of all coins listed in a crypto-exchange prior to a pump. The model exhibits high precision as well as robustness, and can be used to create a simple, yet very effective trading strategy, which we empirically demonstrate can generate a return as high as 60% on small retail investments within a span of two and half months. The study provides a proof of concept for strategic crypto-trading and sheds light on the application of machine learning for crime detection.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"13 1","pages":"1609-1625"},"PeriodicalIF":0.0,"publicationDate":"2018-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82165549","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}
Moritz Lipp, Michael Schwarz, D. Gruss, Thomas Prescher, Werner Haas, Anders Fogh, Jann Horn, S. Mangard, P. Kocher, Daniel Genkin, Y. Yarom, Michael Hamburg
The security of computer systems fundamentally relies on memory isolation, e.g., kernel address ranges are marked as non-accessible and are protected from user access. In this paper, we present Meltdown. Meltdown exploits side effects of out-of-order execution on modern processors to read arbitrary kernel-memory locations including personal data and passwords. Out-of-order execution is an indispensable performance feature and present in a wide range of modern processors. The attack is independent of the operating system, and it does not rely on any software vulnerabilities. Meltdown breaks all security guarantees provided by address space isolation as well as paravirtualized environments and, thus, every security mechanism building upon this foundation. On affected systems, Meltdown enables an adversary to read memory of other processes or virtual machines in the cloud without any permissions or privileges, affecting millions of customers and virtually every user of a personal computer. We show that the KAISER defense mechanism for KASLR has the important (but inadvertent) side effect of impeding Meltdown. We stress that KAISER must be deployed immediately to prevent large-scale exploitation of this severe information leakage.
{"title":"Meltdown: Reading Kernel Memory from User Space","authors":"Moritz Lipp, Michael Schwarz, D. Gruss, Thomas Prescher, Werner Haas, Anders Fogh, Jann Horn, S. Mangard, P. Kocher, Daniel Genkin, Y. Yarom, Michael Hamburg","doi":"10.1145/3357033","DOIUrl":"https://doi.org/10.1145/3357033","url":null,"abstract":"The security of computer systems fundamentally relies on memory isolation, e.g., kernel address ranges are marked as non-accessible and are protected from user access. In this paper, we present Meltdown. Meltdown exploits side effects of out-of-order execution on modern processors to read arbitrary kernel-memory locations including personal data and passwords. Out-of-order execution is an indispensable performance feature and present in a wide range of modern processors. The attack is independent of the operating system, and it does not rely on any software vulnerabilities. Meltdown breaks all security guarantees provided by address space isolation as well as paravirtualized environments and, thus, every security mechanism building upon this foundation. On affected systems, Meltdown enables an adversary to read memory of other processes or virtual machines in the cloud without any permissions or privileges, affecting millions of customers and virtually every user of a personal computer. We show that the KAISER defense mechanism for KASLR has the important (but inadvertent) side effect of impeding Meltdown. We stress that KAISER must be deployed immediately to prevent large-scale exploitation of this severe information leakage.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"180 1","pages":"973-990"},"PeriodicalIF":0.0,"publicationDate":"2018-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72717919","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}
Once a computer system has been infected with malware, restoring it to an uninfected state often requires costly service-interrupting actions such as rolling back to a stable snapshot or reimaging the system entirely. We present CRIU-MR: a technique for restoring an infected server system running within a Linux container to an uninfected state in a service-preserving manner using Checkpoint/Restore in Userspace (CRIU). We modify the CRIU source code to flexibly integrate with existing malware detection technologies so that it can remove suspected malware processes within a Linux container during a checkpoint/restore event. This allows for infected containers with a potentially damaged filesystem to be checkpointed and subsequently restored on a fresh backup filesystem while both removing malware processes and preserving the state of trusted ones. This method can be quickly performed with minimal impact on service availability, restoring active TCP connections and completely removing several types of malware from infected Linux containers.
{"title":"Fast and Service-preserving Recovery from Malware Infections Using CRIU","authors":"Ashton Webster, Ryan Eckenrod, James M. Purtilo","doi":"10.13016/M2QN5ZD12","DOIUrl":"https://doi.org/10.13016/M2QN5ZD12","url":null,"abstract":"Once a computer system has been infected with malware, restoring it to an uninfected state often requires costly service-interrupting actions such as rolling back to a stable snapshot or reimaging the system entirely. We present CRIU-MR: a technique for restoring an infected server system running within a Linux container to an uninfected state in a service-preserving manner using Checkpoint/Restore in Userspace (CRIU). We modify the CRIU source code to flexibly integrate with existing malware detection technologies so that it can remove suspected malware processes within a Linux container during a checkpoint/restore event. This allows for infected containers with a potentially damaged filesystem to be checkpointed and subsequently restored on a fresh backup filesystem while both removing malware processes and preserving the state of trusted ones. This method can be quickly performed with minimal impact on service availability, restoring active TCP connections and completely removing several types of malware from infected Linux containers.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"59 1","pages":"1199-1211"},"PeriodicalIF":0.0,"publicationDate":"2018-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90910369","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}
The need for power- and energy-efficient computing has resulted in aggressive cooperative hardware-software energy management mechanisms on modern commodity devices. Most systems today, for example, allow software to control the frequency and voltage of the underlying hardware at a very fine granularity to extend battery life. Despite their benefits, these software-exposed energy management mechanisms pose grave security implications that have not been studied before. In this work, we present the CLK SCREW attack, a new class of fault attacks that exploit the security-obliviousness of energy management mechanisms to break security. A novel benefit for the attackers is that these fault attacks become more accessible since they can now be conducted without the need for physical access to the devices or fault injection equipment. We demonstrate CLK SCREW on commodity ARM/Android devices. We show that a malicious kernel driver (1) can extract secret cryptographic keys from Trustzone, and (2) can escalate its privileges by loading self-signed code into Trustzone. As the first work to show the security ramifications of energy management mechanisms, we urge the community to re-examine these security-oblivious designs.
{"title":"CLKSCREW: Exposing the Perils of Security-Oblivious Energy Management","authors":"Adrian Tang, S. Sethumadhavan, S. Stolfo","doi":"10.7916/d8-0ytv-3a53","DOIUrl":"https://doi.org/10.7916/d8-0ytv-3a53","url":null,"abstract":"The need for power- and energy-efficient computing has resulted in aggressive cooperative hardware-software energy management mechanisms on modern commodity devices. Most systems today, for example, allow software to control the frequency and voltage of the underlying hardware at a very fine granularity to extend battery life. Despite their benefits, these software-exposed energy management mechanisms pose grave security implications that have not been studied before. In this work, we present the CLK SCREW attack, a new class of fault attacks that exploit the security-obliviousness of energy management mechanisms to break security. A novel benefit for the attackers is that these fault attacks become more accessible since they can now be conducted without the need for physical access to the devices or fault injection equipment. We demonstrate CLK SCREW on commodity ARM/Android devices. We show that a malicious kernel driver (1) can extract secret cryptographic keys from Trustzone, and (2) can escalate its privileges by loading self-signed code into Trustzone. As the first work to show the security ramifications of energy management mechanisms, we urge the community to re-examine these security-oblivious designs.","PeriodicalId":91597,"journal":{"name":"Proceedings of the ... USENIX Security Symposium. UNIX Security Symposium","volume":"95 1","pages":"1057-1074"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77282730","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}