Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security最新文献

{"title":"Side Channels in Deduplication: Trade-offs between Leakage and Efficiency","authors":"Frederik Armknecht, C. Boyd, Gareth T. Davies, Kristian Gjøsteen, Mohsen Toorani","doi":"10.1145/3052973.3053019","DOIUrl":"https://doi.org/10.1145/3052973.3053019","url":null,"abstract":"Deduplication removes redundant copies of files or data blocks stored on the cloud. Client-side deduplication, where the client only uploads the file upon the request of the server, provides major storage and bandwidth savings, but introduces a number of security concerns. Harnik et al. (2010) showed how cross-user client-side deduplication inherently gives the adversary access to a (noisy) side-channel that may divulge whether or not a particular file is stored on the server, leading to leakage of user information. We provide formal definitions for deduplication strategies and their security in terms of adversarial advantage. Using these definitions, we provide a criterion for designing good strategies and then prove a bound characterizing the necessary trade-off between security and efficiency.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89629320","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: Memory Corruption Att. & Def.","authors":"Heng Yin","doi":"10.1145/3248550","DOIUrl":"https://doi.org/10.1145/3248550","url":null,"abstract":"","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90974846","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":"To Update or Not to Update: Insights From a Two-Year Study of Android App Evolution","authors":"Vincent F. Taylor, I. Martinovic","doi":"10.1145/3052973.3052990","DOIUrl":"https://doi.org/10.1145/3052973.3052990","url":null,"abstract":"Although there are over 1,900,000 third-party Android apps in the Google Play Store, little is understood about how their security and privacy characteristics, such as dangerous permission usage and the vulnerabilities they contain, have evolved over time. Our research is two-fold: we take quarterly snapshots of the Google Play Store over a two-year period to understand how permission usage by apps has changed; and we analyse 30,000 apps to understand how their security and privacy characteristics have changed over the same two-year period. Extrapolating our findings, we estimate that over 35,000 apps in the Google Play Store ask for additional dangerous permissions every three months. Our statistically significant observations suggest that free apps and popular apps are more likely to ask for additional dangerous permissions when they are updated. Worryingly, we discover that Android apps are not getting safer as they are updated. In many cases, app updates serve to increase the number of distinct vulnerabilities contained within apps, especially for popular apps. We conclude with recommendations to stakeholders for improving the security of the Android ecosystem.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80333830","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: SGX","authors":"Mathias Payer","doi":"10.1145/3248547","DOIUrl":"https://doi.org/10.1145/3248547","url":null,"abstract":"","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86523451","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":"VTBPEKE: Verifier-based Two-Basis Password Exponential Key Exchange","authors":"D. Pointcheval, Guilin Wang","doi":"10.1145/3052973.3053026","DOIUrl":"https://doi.org/10.1145/3052973.3053026","url":null,"abstract":"PAKE protocols, for Password-Authenticated Key Exchange, enable two parties to establish a shared cryptographically strong key over an insecure network using a short common secret as authentication means. After the seminal work by Bellovin and Merritt, with the famous EKE, for Encrypted Key Exchange, various settings and security notions have been defined, and many protocols have been proposed. In this paper, we revisit the promising SPEKE, for Simple Password Exponential Key Exchange, proposed by Jablon. The only known security analysis works in the random oracle model under the CDH assumption, but in the multiplicative groups of finite fields only (subgroups of Zp*), which means the use of large elements and so huge communications and computations. Our new instantiation (TBPEKE, for Two-Basis Password Exponential Key Exchange) applies to any group, and our security analysis requires a DLIN-like assumption to hold. In particular, one can use elliptic curves, which leads to a better efficiency, at both the communication and computation levels. We additionally consider server corruptions, which immediately leak all the passwords to the adversary with symmetric PAKE. We thus study an asymmetric variant, also known as VPAKE, for Verifier-based Password Authenticated Key Exchange. We then propose a verifier-based variant of TBPEKE, the so-called VTBPEKE, which is also quite efficient, and resistant to server-compromise.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"50 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86731931","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":"Hardware Trojans and Other Threats against Embedded Systems","authors":"C. Paar","doi":"10.1145/3052973.3053885","DOIUrl":"https://doi.org/10.1145/3052973.3053885","url":null,"abstract":"Countless systems ranging from consumer electronics to military equipment are dependent on integrated circuits (ICs). A surprisingly large number of such systems are already security- critical, e.g., automotive electronics, medical devices, or SCADA systems. If the underlying ICs in such applications are maliciously manipulated through hardware Trojans, the security of the entire system can be compromised. In recent years, hardware Trojans have drawn the attention of the scientific community and government. Initially, the primary attacker model was a malicious foundry that could alter the design, i.e., introduce hardware Trojans which could interfere with the functionality of a chip. Many other attacker models exist too. For instance, a legitimate IC manufacturer, such as a consumer electronics company, might be in cohort with a national intelligence agency and could alter its products in a way that compromises their security. Even though hardware Trojans have been studied for a decade or so in the literature, little is known about how they might look, and what the \"use cases\" for them is. We describe two applications for low-level hardware manipulations. One introduces an ASIC Trojans by sub-transistor changes, and the other is a novel type of fault-injection attacks against FPGAs. As an example for an extremely stealthy manipulations, we show how a dangerous Trojans can be introduced by merely changing the dopant polarity of selected existing transistors of a design. The Trojan manipulates the digital post-processing of Intel's cryptographically secure random number generator used in the Ivy Bridge processors. The adversary is capable of exactly controlling the entropy of the RNG. For example, the attacker can reduce the RNG's entropy to 40 bits of randomness. Due to the AES-based one-way function after the entropy extracting, the Trojan is very difficult to detect. Crucially, this approach does not require to add new circuits to the IC. Since the modified circuit appears legitimate on all wiring layers (including all metal and polysilicon), our family of Trojans is resistant to many detection techniques, including fine-grain optical inspection and checking against \"golden chips\". As a second \"use case\", we show how an adversary can extract cryptographic keys from an unknown FPGA design. The attack, coined bitstream fault injection (BiFI), systematically manipulates the bitstream by changing random LUT contents, configures the target device, and collects the resulting faulty ciphertexts. The ciphertexts are used to recover the key by testing a set of hypotheses, e.g., that the ciphertext is the plaintext XORed with the key. The attack only needs a black-box assumption about the bitstream structure and format. It was verified by considering a set of 3 rd party AES designs on different standard FPGAs. In 15 out of 16 designs, we were able to extract the AES key.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"19 1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83040351","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":"A Terrorist-fraud Resistant and Extractor-free Anonymous Distance-bounding Protocol","authors":"Gildas Avoine, Xavier Bultel, S. Gambs, David Gérault, P. Lafourcade, Cristina Onete, J. Robert","doi":"10.1145/3052973.3053000","DOIUrl":"https://doi.org/10.1145/3052973.3053000","url":null,"abstract":"Distance-bounding protocols have been introduced to thwart relay attacks against contactless authentication protocols. In this context, verifiers have to authenticate the credentials of untrusted provers. Unfortunately, these protocols are themselves subject to complex threats such as terrorist-fraud attacks, in which a malicious prover helps an accomplice to authenticate. Provably guaranteeing the resistance of distance-bounding protocols to these attacks is complex. The classical solutions assume that rational provers want to protect their long-term authentication credentials, even with respect to their accomplices. Thus, terrorist-fraud resistant protocols generally rely on artificial extraction mechanisms, ensuring that an accomplice can retrieve the credential of his partnering prover, if he is able to authenticate. We propose a novel approach to obtain provable terrorist-fraud resistant protocols that does not rely on an accomplice being able to extract any long-term key. Instead, we simply assume that he can replay the information received from the prover. Thus, rational provers should refuse to cooperate with third parties if they can impersonate them freely afterwards. We introduce a generic construction for provably secure distance-bounding protocols, and give three instances of this construction: (1) an efficient symmetric-key protocol, (2) a public-key protocol protecting the identities of provers against external eavesdroppers, and finally (3) a fully anonymous protocol protecting the identities of provers even against malicious verifiers that try to profile them.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87708881","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":"Pass-O: A Proposal to Improve the Security of Pattern Unlock Scheme","authors":"Harshal Tupsamudre, Vijayanand Banahatti, S. Lodha, Ketan Vyas","doi":"10.1145/3052973.3053041","DOIUrl":"https://doi.org/10.1145/3052973.3053041","url":null,"abstract":"The graphical pattern unlock scheme which requires users to connect a minimum of 4 nodes on 3X3 grid is one of the most popular authentication mechanism on mobile devices. However prior research suggests that users' pattern choices are highly biased and hence vulnerable to guessing attacks. Moreover, 3X3 pattern choices are devoid of features such as longer stroke lengths, direction changes and intersections that are considered to be important in preventing shoulder-surfing attacks. We attribute these insecure practices to the geometry of the grid and its complicated drawing rules which prevent users from realising the full potential of graphical passwords. In this paper, we propose and explore an alternate circular layout referred to as Pass-O which unlike grid layout allows connection between any two nodes, thus simplifying the pattern drawing rules. Consequently, Pass-O produces a theoretical search space of 9,85,824, almost 2.5 times greater than 3X3 grid layout. We compare the security of 3X3 and Pass-O patterns theoretically as well as empirically. Theoretically, Pass-O patterns are uniform and have greater visual complexity due to large number of intersections. To perform empirical analysis, we conduct a large-scale web-based user study and collect more than 1,23,000 patterns from 21,053 users. After examining user-chosen 3X3 and Pass-O patterns across different metrics such as pattern length, stroke length, start point, end point, repetitions, number of direction changes and intersections, we find that Pass-O patterns are much more secure than 3X3 patterns.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76343637","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":"Security in Personal Genomics: Lest We Forget","authors":"G. Tsudik","doi":"10.1145/3052973.3056128","DOIUrl":"https://doi.org/10.1145/3052973.3056128","url":null,"abstract":"Genomic privacy has attracted much attention from the research community, mainly since its risks are unique and breaches can lead to terrifying leakage of most personal and sensitive information. The much less explored topic of genomic security needs to mitigate threats of the digitized genome being altered by its owner or an outside party, which can have dire consequences, especially, in medical or legal settings. At the same time, many anticipated genomic applications (with varying degrees of trust) require only small amounts of genomic data. Supporting such applications requires a careful balance between security and privacy. Furthermore, genome's size raises performance concerns. We argue that genomic security must be taken seriously and explored as a research topic in its own right. To this end, we discuss the problem space, identify the stakeholders, discuss assumptions about them, and outline several simple approaches based on common cryptographic techniques, including signature variants and authenticated data structures. We also present some extensions and identify opportunities for future research. The main goal of this paper is to highlight the importance of genomic security as a research topic in its own right.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77376720","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":"Almost Universal Forgery Attacks on the COPA and Marble Authenticated Encryption Algorithms","authors":"Jiqiang Lu","doi":"10.1145/3052973.3052981","DOIUrl":"https://doi.org/10.1145/3052973.3052981","url":null,"abstract":"The COPA authenticated encryption mode was proved to have a birthday-bound security on integrity, and its instantiation AES-COPA (v1/2) was claimed or conjectured to have a full security on tag guessing. The Marble (v1.0/1.1/1.2) authenticated encryption algorithm was claimed to have a full security on authenticity. Both AES-COPA (v1) and Marble (v1.0) were submitted to the Competition for Authenticated Encryption: Security, Applicability, and Robustness (CAESAR) in 2014, and Marble was revised twice (v1.1/1.2) in the first round of CAESAR, and AES-COPA (v1) was tweaked (v2) for the second round of CAESAR. In this paper, we cryptanalyse the basic cases of COPA, AES-COPA and Marble, that process messages of a multiple of the block size long; we present collision-based almost universal forgery attacks on the basic cases of COPA, AES-COPA (v1/2) and Marble (v1.0/1.1/1.2), and show that the basic cases of COPA and AES-COPA have roughly at most a birthday-bound security on tag guessing and the basic case of Marble has roughly at most a birthday-bound security on authenticity. The attacks on COPA and AES-COPA do not violate their birthday-bound security proof on integrity, but the attack on AES-COPA violates its full security claim or conjecture on tag guessing. Therefore, the full security claim or conjecture on tag guessing of AES-COPA and the full security claim on authenticity of Marble are incorrectly far overestimated in the sense of a general understanding of full security of these security notions. Designers should pay attention to these attacks when designing authenticated encryption algorithms with similar structures in the future, and should be careful when claiming the security of an advanced form of a security notion without making a corresponding proof after proving the security of the security notion only under its most fundamental form.","PeriodicalId":20540,"journal":{"name":"Proceedings of the 2017 ACM on Asia Conference on Computer and Communications Security","volume":"84 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2017-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73754244","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}