Riccardo Paccagnella, Kevin Liao, D. Tian, Adam Bates
For system logs to aid in security investigations, they must be beyond the reach of the adversary. Unfortunately, attackers that have escalated privilege on a host are typically able to delete and modify log events at will. In response to this threat, a variety of secure logging systems have appeared over the years that attempt to provide tamper-resistance (e.g., write once read many drives, remote storage servers) or tamper-evidence (e.g., cryptographic proofs) for system logs. These solutions expose an interface through which events are committed to a secure log, at which point they enjoy protection from future tampering. However, all proposals to date have relied on the assumption that an event's occurrence is concomitant with its commitment to the secured log. In this work, we challenge this assumption by presenting and validating a race condition attack on the integrity of audit frameworks. Our attack exploits the intrinsically asynchronous nature of I/O and IPC activity, demonstrating that an attacker can snatch events about their intrusion out of message buffers after they have occurred but before they are committed to the log, thus bypassing existing protections. We present a first step towards defending against our attack by introducing KennyLoggings, the first kernel- based tamper-evident logging system that satisfies the synchronous integrity property, meaning that it guarantees tamper-evidence of events upon their occurrence. We implement KennyLoggings on top of the Linux kernel and show that it imposes between 8% and 11% overhead on log-intensive application workloads.
{"title":"Logging to the Danger Zone: Race Condition Attacks and Defenses on System Audit Frameworks","authors":"Riccardo Paccagnella, Kevin Liao, D. Tian, Adam Bates","doi":"10.1145/3372297.3417862","DOIUrl":"https://doi.org/10.1145/3372297.3417862","url":null,"abstract":"For system logs to aid in security investigations, they must be beyond the reach of the adversary. Unfortunately, attackers that have escalated privilege on a host are typically able to delete and modify log events at will. In response to this threat, a variety of secure logging systems have appeared over the years that attempt to provide tamper-resistance (e.g., write once read many drives, remote storage servers) or tamper-evidence (e.g., cryptographic proofs) for system logs. These solutions expose an interface through which events are committed to a secure log, at which point they enjoy protection from future tampering. However, all proposals to date have relied on the assumption that an event's occurrence is concomitant with its commitment to the secured log. In this work, we challenge this assumption by presenting and validating a race condition attack on the integrity of audit frameworks. Our attack exploits the intrinsically asynchronous nature of I/O and IPC activity, demonstrating that an attacker can snatch events about their intrusion out of message buffers after they have occurred but before they are committed to the log, thus bypassing existing protections. We present a first step towards defending against our attack by introducing KennyLoggings, the first kernel- based tamper-evident logging system that satisfies the synchronous integrity property, meaning that it guarantees tamper-evidence of events upon their occurrence. We implement KennyLoggings on top of the Linux kernel and show that it imposes between 8% and 11% overhead on log-intensive application workloads.","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"162 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78531729","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}
Jiaheng Zhang, Zhiyong Fang, Yupeng Zhang, D. Song
Machine learning has become increasingly prominent and is widely used in various applications in practice. Despite its great success, the integrity of machine learning predictions and accuracy is a rising concern. The reproducibility of machine learning models that are claimed to achieve high accuracy remains challenging, and the correctness and consistency of machine learning predictions in real products lack any security guarantees. In this paper, we initiate the study of zero knowledge machine learning and propose protocols for zero knowledge decision tree predictions and accuracy tests. The protocols allow the owner of a decision tree model to convince others that the model computes a prediction on a data sample, or achieves a certain accuracy on a public dataset, without leaking any information about the model itself. We develop approaches to efficiently turn decision tree predictions and accuracy into statements of zero knowledge proofs. We implement our protocols and demonstrate their efficiency in practice. For a decision tree model with 23 levels and 1,029 nodes, it only takes 250 seconds to generate a zero knowledge proof proving that the model achieves high accuracy on a dataset of 5,000 samples and 54 attributes, and the proof size is around 287 kilobytes.
{"title":"Zero Knowledge Proofs for Decision Tree Predictions and Accuracy","authors":"Jiaheng Zhang, Zhiyong Fang, Yupeng Zhang, D. Song","doi":"10.1145/3372297.3417278","DOIUrl":"https://doi.org/10.1145/3372297.3417278","url":null,"abstract":"Machine learning has become increasingly prominent and is widely used in various applications in practice. Despite its great success, the integrity of machine learning predictions and accuracy is a rising concern. The reproducibility of machine learning models that are claimed to achieve high accuracy remains challenging, and the correctness and consistency of machine learning predictions in real products lack any security guarantees. In this paper, we initiate the study of zero knowledge machine learning and propose protocols for zero knowledge decision tree predictions and accuracy tests. The protocols allow the owner of a decision tree model to convince others that the model computes a prediction on a data sample, or achieves a certain accuracy on a public dataset, without leaking any information about the model itself. We develop approaches to efficiently turn decision tree predictions and accuracy into statements of zero knowledge proofs. We implement our protocols and demonstrate their efficiency in practice. For a decision tree model with 23 levels and 1,029 nodes, it only takes 250 seconds to generate a zero knowledge proof proving that the model achieves high accuracy on a dataset of 5,000 samples and 54 attributes, and the proof size is around 287 kilobytes.","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"111 3S 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76090561","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}
Frederik Armknecht, Paul Walther, G. Tsudik, Martin Beck, T. Strufe
Efficiently integrity verification of received data requires Message Authentication Code (MAC) tags. However, while security calls for rather long tags, in many scenarios this contradicts other requirements. Examples are strict delay requirements (e.g., robot or drone control) or resource-scarce settings (e.g., LoRaWAN networks with limited battery capacity). Prior techniques suggested truncation of MAC tags, thus trading off linear performance gain for exponential security loss. To achieve security of full-length MACs with short(er) tags, we introduce Progressive MACs (ProMACs) -- a scheme that uses internal state to gradually increase security upon reception of subsequent messages. We provide a formal framework and propose a provably secure, generic construction called Whips. We evaluate applicability of ProMACs in several realistic scenarios and demonstrate example settings where ProMACs can be used as a drop-in replacement for traditional MACs.
{"title":"ProMACs: Progressive and Resynchronizing MACs for Continuous Efficient Authentication of Message Streams","authors":"Frederik Armknecht, Paul Walther, G. Tsudik, Martin Beck, T. Strufe","doi":"10.1145/3372297.3423349","DOIUrl":"https://doi.org/10.1145/3372297.3423349","url":null,"abstract":"Efficiently integrity verification of received data requires Message Authentication Code (MAC) tags. However, while security calls for rather long tags, in many scenarios this contradicts other requirements. Examples are strict delay requirements (e.g., robot or drone control) or resource-scarce settings (e.g., LoRaWAN networks with limited battery capacity). Prior techniques suggested truncation of MAC tags, thus trading off linear performance gain for exponential security loss. To achieve security of full-length MACs with short(er) tags, we introduce Progressive MACs (ProMACs) -- a scheme that uses internal state to gradually increase security upon reception of subsequent messages. We provide a formal framework and propose a provably secure, generic construction called Whips. We evaluate applicability of ProMACs in several realistic scenarios and demonstrate example settings where ProMACs can be used as a drop-in replacement for traditional MACs.","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76184584","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}
{"title":"Session details: Session 2C: Browser Security","authors":"A. Kapravelos","doi":"10.1145/3432964","DOIUrl":"https://doi.org/10.1145/3432964","url":null,"abstract":"","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75773963","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}
Clouds and massive-scale computing infrastructures are starting to dominate computing and will likely continue to do so for the foreseeable future. Major cloud operators are now comprising millions of cores hosting substantial fractions of corporate and government IT infrastructure. CCSW is the world's premier forum bringing together researchers and practitioners in all security aspects of cloud-centric and outsourced computing, including: Side channel attacks; Practical cryptographic protocols for cloud security; Secure cloud resource virtualization mechanisms; Secure data management outsourcing (e.g., database as a service); Practical privacy and integrity mechanisms for outsourcing; Foundations of cloud-centric threat models; Secure computation outsourcing; Remote attestation mechanisms in clouds; Sandboxing and VM-based enforcements; Trust and policy management in clouds; Secure identity management mechanisms; New cloud-aware web service security paradigms and mechanisms; Cloud-centric regulatory compliance issues and mechanisms; Business and security risk models and clouds; Cost and usability models and their interaction with security in clouds; Scalability of security in global-size clouds; Trusted computing technology and clouds; Binary analysis of software for remote attestation and cloud protection; Network security (DOS, IDS etc.) mechanisms for cloud contexts; Security for emerging cloud programming models; Energy/cost/efficiency of security in clouds; Machine learning for cloud protection CCSW especially encourages novel paradigms and controversial ideas that are not on the above list. The workshop has historically acted as a fertile ground for creative debate and interaction in security-sensitive areas of computing impacted by clouds. This year marked the 11th anniversary of CCSW. In the past decade, CCSW has had a significant impact in our research community. As of August 2019, in the Google Scholar Metrics entry for ACM CCS (which encompasses CCSW), 20% of the top 20 cited papers come from CCSW. One way to look at it is that authors are as likely or perhaps more likely to have a top-20 paper publishing in CCSW than in CCS! This year, CCSW received 40 submissions out of which 12 full papers (30%) and 5 blitz abstracts were accepted.
{"title":"CCSW'20: 2020 Cloud Computing Security Workshop","authors":"R. Sion, Yinqian Zhang","doi":"10.1145/3372297.3416242","DOIUrl":"https://doi.org/10.1145/3372297.3416242","url":null,"abstract":"Clouds and massive-scale computing infrastructures are starting to dominate computing and will likely continue to do so for the foreseeable future. Major cloud operators are now comprising millions of cores hosting substantial fractions of corporate and government IT infrastructure. CCSW is the world's premier forum bringing together researchers and practitioners in all security aspects of cloud-centric and outsourced computing, including: Side channel attacks; Practical cryptographic protocols for cloud security; Secure cloud resource virtualization mechanisms; Secure data management outsourcing (e.g., database as a service); Practical privacy and integrity mechanisms for outsourcing; Foundations of cloud-centric threat models; Secure computation outsourcing; Remote attestation mechanisms in clouds; Sandboxing and VM-based enforcements; Trust and policy management in clouds; Secure identity management mechanisms; New cloud-aware web service security paradigms and mechanisms; Cloud-centric regulatory compliance issues and mechanisms; Business and security risk models and clouds; Cost and usability models and their interaction with security in clouds; Scalability of security in global-size clouds; Trusted computing technology and clouds; Binary analysis of software for remote attestation and cloud protection; Network security (DOS, IDS etc.) mechanisms for cloud contexts; Security for emerging cloud programming models; Energy/cost/efficiency of security in clouds; Machine learning for cloud protection CCSW especially encourages novel paradigms and controversial ideas that are not on the above list. The workshop has historically acted as a fertile ground for creative debate and interaction in security-sensitive areas of computing impacted by clouds. This year marked the 11th anniversary of CCSW. In the past decade, CCSW has had a significant impact in our research community. As of August 2019, in the Google Scholar Metrics entry for ACM CCS (which encompasses CCSW), 20% of the top 20 cited papers come from CCSW. One way to look at it is that authors are as likely or perhaps more likely to have a top-20 paper publishing in CCSW than in CCS! This year, CCSW received 40 submissions out of which 12 full papers (30%) and 5 blitz abstracts were accepted.","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75476804","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}
Anonymous Committed Broadcast is a functionality that extends DC-nets and allows a set of clients to privately commit messages to set of servers, which can then simultaneously open all committed messages in a random ordering. Anonymity holds since no one can learn the ordering or the content of the client's committed message. We present Blinder, the first system that provides a scalable and fully robust solution for anonymous committed broadcast. Blinder maintains both properties of security (anonymity) and robustness (aka. 'guaranteed output delivery' or 'availability') in the face of a global active (malicious) adversary. Moreover, Blinder is censorship resistant, that is, an honest client cannot be blocked from participating. Blinder obtains its security and scalability by carefully combining classical and state-of-the-art techniques from the fields of anonymous communication and secure multiparty computation (MPC). Relying on MPC for such a system is beneficial since it naturally allows the parties (servers) to enforce some properties on accepted messages prior their publication. A GPU based implementation of Blinder with 5 servers, which accepts 1 million clients, incurs a latency of less than 8 minutes; faster by a factor of $>100$ than the 3-servers Riposte protocol (S&P '15), which is not robust and not censorship resistant; we get an even larger factor when comparing to AsynchroMix and PowerMix (CCS '19), which are the only ones that guarantee fairness (or robustness in the online phase).
{"title":"Blinder -- Scalable, Robust Anonymous Committed Broadcast","authors":"Ittai Abraham, Benny Pinkas, Avishay Yanai","doi":"10.1145/3372297.3417261","DOIUrl":"https://doi.org/10.1145/3372297.3417261","url":null,"abstract":"Anonymous Committed Broadcast is a functionality that extends DC-nets and allows a set of clients to privately commit messages to set of servers, which can then simultaneously open all committed messages in a random ordering. Anonymity holds since no one can learn the ordering or the content of the client's committed message. We present Blinder, the first system that provides a scalable and fully robust solution for anonymous committed broadcast. Blinder maintains both properties of security (anonymity) and robustness (aka. 'guaranteed output delivery' or 'availability') in the face of a global active (malicious) adversary. Moreover, Blinder is censorship resistant, that is, an honest client cannot be blocked from participating. Blinder obtains its security and scalability by carefully combining classical and state-of-the-art techniques from the fields of anonymous communication and secure multiparty computation (MPC). Relying on MPC for such a system is beneficial since it naturally allows the parties (servers) to enforce some properties on accepted messages prior their publication. A GPU based implementation of Blinder with 5 servers, which accepts 1 million clients, incurs a latency of less than 8 minutes; faster by a factor of $>100$ than the 3-servers Riposte protocol (S&P '15), which is not robust and not censorship resistant; we get an even larger factor when comparing to AsynchroMix and PowerMix (CCS '19), which are the only ones that guarantee fairness (or robustness in the online phase).","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"88 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74202666","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}
{"title":"Session details: Session 4C: Kernel Security","authors":"Erik van der Kouwe","doi":"10.1145/3432974","DOIUrl":"https://doi.org/10.1145/3432974","url":null,"abstract":"","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74716080","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}
{"title":"Session details: Session 5C: Forensics","authors":"Juan Caballero","doi":"10.1145/3432979","DOIUrl":"https://doi.org/10.1145/3432979","url":null,"abstract":"","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"104 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73643692","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}
R. Canetti, R. Gennaro, Steven Goldfeder, Nikolaos Makriyannis, Udi Peled
Building on the Gennaro & Goldfeder and Lindell & Nof protocols (CCS '18), we present two threshold ECDSA protocols, for any number of signatories and any threshold, that improve as follows over the state of the art: -- For both protocols, only the last round requires knowledge of the message, and the other rounds can take place in a preprocessing stage, lending to a non-interactive threshold ECDSA protocol. -- Both protocols withstand adaptive corruption of signatories. Furthermore, they include a periodic refresh mechanism and offer full proactive security. -- Both protocols realize an ideal threshold signature functionality within the UC framework, in the global random oracle model, assuming Strong RSA, DDH, semantic security of the Paillier encryption, and a somewhat enhanced variant of existential unforgeability of ECDSA. -- Both protocols achieve accountability by identifying corrupted parties in case of failure to generate a valid signature. The two protocols are distinguished by the round-complexity and the identification process for detecting cheating parties. Namely: -- For the first protocol, signature generation takes only 4 rounds (down from the current state of the art of 8 rounds), but the identification process requires computation and communication that is quadratic in the number of parties. -- For the second protocol, the identification process requires computation and communication that is only linear in the number of parties, but signature generation takes 7 rounds. These properties (low latency, compatibility with cold-wallet architectures, proactive security, identifiable abort and composable security) make the two protocols ideal for threshold wallets for ECDSA-based cryptocurrencies.
{"title":"UC Non-Interactive, Proactive, Threshold ECDSA with Identifiable Aborts","authors":"R. Canetti, R. Gennaro, Steven Goldfeder, Nikolaos Makriyannis, Udi Peled","doi":"10.1145/3372297.3423367","DOIUrl":"https://doi.org/10.1145/3372297.3423367","url":null,"abstract":"Building on the Gennaro & Goldfeder and Lindell & Nof protocols (CCS '18), we present two threshold ECDSA protocols, for any number of signatories and any threshold, that improve as follows over the state of the art: -- For both protocols, only the last round requires knowledge of the message, and the other rounds can take place in a preprocessing stage, lending to a non-interactive threshold ECDSA protocol. -- Both protocols withstand adaptive corruption of signatories. Furthermore, they include a periodic refresh mechanism and offer full proactive security. -- Both protocols realize an ideal threshold signature functionality within the UC framework, in the global random oracle model, assuming Strong RSA, DDH, semantic security of the Paillier encryption, and a somewhat enhanced variant of existential unforgeability of ECDSA. -- Both protocols achieve accountability by identifying corrupted parties in case of failure to generate a valid signature. The two protocols are distinguished by the round-complexity and the identification process for detecting cheating parties. Namely: -- For the first protocol, signature generation takes only 4 rounds (down from the current state of the art of 8 rounds), but the identification process requires computation and communication that is quadratic in the number of parties. -- For the second protocol, the identification process requires computation and communication that is only linear in the number of parties, but signature generation takes 7 rounds. These properties (low latency, compatibility with cold-wallet architectures, proactive security, identifiable abort and composable security) make the two protocols ideal for threshold wallets for ECDSA-based cryptocurrencies.","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83004876","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}
{"title":"Session details: Keynote Talk I","authors":"Jonathan Katz","doi":"10.1145/3432956","DOIUrl":"https://doi.org/10.1145/3432956","url":null,"abstract":"","PeriodicalId":20481,"journal":{"name":"Proceedings of the 2020 ACM SIGSAC Conference on Computer and Communications Security","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84485766","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}
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