IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
02 April 2020
David Knichel, Thorben Moos, Amir Moradi
ePrint ReportDorian Amiet, Andreas Curiger, Lukas Leuenberger, Paul Zbinden
ePrint ReportMarcel Tiepelt, Jan-Pieter D'Anvers
ePrint ReportWe implemented our attack on a simplified version of the code submitted to the NIST competition. Our attack is able to extract a good estimate of the secrets using $2^{12}$ decryption failures, corresponding to $2^{74}$~failing ciphertexts in the original scheme. Subsequently the exact secrets can be extracted in $O(2^{46})$ quantum computational steps.
Hangwei Lu, Dhwani Mehta, Olivia Paradis, Navid Asadizanjani, Mark Tehranipoor, Damon L. Woodard
ePrint ReportSankhanil Dey, Amlan Chakrabarti, Ranjan Ghosh
ePrint Report01 April 2020
Guildford, United Kingdom, 18 September 2020
Event CalendarSubmission deadline: 25 June 2020
Notification: 30 July 2020
Amsterdam, The Netherlands, 11 January - 13 January 2021
Real World CryptoSubmission deadline: 1 September 2020
Notification: 1 November 2020
31 March 2020
Eurocrypt
The dates and details of the new all-digital event will be communicated at a later time via the IACR news system, the conference website, and other appropriate communication channels.
The locations and dates of EUROCRYPT 2021 and EUROCRYPT 2022 have also changed as follows:
- EUROCRYPT 2021 will take place in Zagreb, Croatia, during May 3-6, 2021;
- EUROCRYPT 2022 will take place in Trondheim, Norway.
The board wishes safety and health to all our members during these challenging times.
28 March 2020
Behzad Abdolmaleki, Daniel Slamanig
ePrint ReportIn this paper, we investigate QA-NIZKs in the aforementioned setting. First, we analyze the security of the most efficient QA-NIZK constructions of Kiltz and Wee (EUROCRYPT'15) and the asymmetric QA-NIZKs by Gonzalez et al. (ASIACRYPT'15) when the CRS is subverted and propose subversion versions of them. Secondly, for the first time, we construct l-time simulation sound and unbounded simulation sound subversion QA-NIZK. Thirdly, we show how to integrate our subversion QA-NIZKs into the LegoSNARK toolbox, where subversion resistance is not yet considered. Our results together with recent subversion zk-SNARKS (Abdolmaleki et al. ASIACRYPT'17; Fuchsbauer PKC'18, Lipmaa EPRINT'19), are an important step towards a subversion variant of the LegoSNARK toolbox. Finally, we believe that our (SS) subversion QA-NIZKs will be of interest beyond the aforementioned application.
Qianhong Wan, Longjiang Qu, Chao Li
ePrint ReportYongge Wang
ePrint ReportReza Azarderakhsh, David Jao, Brian Koziel, Jason T. LeGrow, Vladimir Soukharev, Oleg Taraskin
ePrint ReportSankhanil Dey, Amlan Chakrabarti, Ranjan Ghosh
ePrint ReportSankhanil Dey, Amlan Chakrabarti, Ranjan Ghosh
ePrint ReportSankhanil Dey, Amlan Chakrabarti, Ranjan Ghosh
ePrint ReportGeorge Teseleanu
ePrint ReportMartin Hirt, Marta Mularczyk
ePrint ReportHowever, these efficient protocols only offer active security, which implies that at most $t<n/3$ (perfect security), respectively $t<n/2$ (statistical or computational security) parties may be corrupted. Higher corruption thresholds (i.e., $t\geq n/2$) can only be achieved with degraded security (unfair abort), where one single corrupted party can prevent honest parties from learning their outputs.
The aforementioned upper bounds ($t<n/3$ and $t<n/2$) have been circumvented by considering mixed adversaries (Fitzi et al., Crypto' 98), i.e., adversaries that corrupt, at the same time, some parties actively, some parties passively, and some parties in the fail-stop manner. It is possible, for example, to achieve perfect security even if $2/3$ of the parties are faulty (three quarters of which may abort in the middle of the protocol, and a quarter may even arbitrarily misbehave). This setting is much better suited to many applications, where the crash of a party is more likely than a coordinated active attack.
Surprisingly, since the presentation of the feasibility result for the mixed setting, no progress has been made in terms of efficiency: the state-of-the-art protocol still requires a communication of $\Omega(n^6)$ field elements per multiplication.
In this paper, we present a perfectly-secure MPC protocol for the mixed setting with essentially the same efficiency as the best MPC protocols for the active-only setting. For the first time, this allows to tolerate faulty majorities, while still providing optimal efficiency. As a special case, this also results in the first fully-secure MPC protocol secure against any number of crashing parties, with optimal (i.e., linear in $n$) communication. We provide simulation-based proofs of our construction.
27 March 2020
University of Warwick
Job PostingThis is a fully-funded Ph.D. position for a UK/EU/International student (tuition fees plus stipend) to pursue a Ph.D. research degree in the Department of Computer Science, University of Warwick. Note that for international students, the overseas tuition gap will be covered as well.
The project is in the area of security and cryptography, in particular, investigating next-generation cryptocurrency that is more scalable, privacy-preserving, and usable than what we have today.
An ideal candidate should have excellent undergraduate and master degrees (equivalent to at least a UK 2.1) in Computer Science or relevant disciplines such as Mathematics and Engineering; a solid mathematical background as well as strong programming skills; experience in security research.
The closing date for application is 30 April 2020.
Interested candidates are encouraged to apply as early as possible. First, express your interest by sending your CV to Prof Feng Hao (feng.hao@warwick.ac.uk). If your background is found suitable, you will be directed to make a formal application. All formal applications will need to be made online through https://warwick.ac.uk/study/postgraduate/apply/research/.
Further information about the research environment: The Department of Computer Science, University of Warwick is one of the leading CS departments in the UK. In the latest 2014 REF (Research Excellence Framework) assessment participated by all UK universities, Warwick Computer Science is ranked the 1st for research output, 2nd for research impact, and 2nd overall among 89 CS departments in the UK. The University of Warwick is consistently ranked among the top 10 universities in the UK. It is also known for its beautiful campus, friendly social environment, vivid student lives, and easy transport links to all major cities in the UK including London.
Closing date for applications:
Contact: Professor Feng Hao
More information: https://warwick.ac.uk/fac/sci/dcs/research/doctoralstudies/fundingadvice/researchstudentships/?newsItem=8a17841b70e3f5d8
Nanyang Technological University / Temasek Labs @ NTU
Job PostingClosing date for applications:
Contact: Thomas Peyrin (thomas.peyrin@ntu.edu.sg)
University of Luxembourg
Job PostingClosing date for applications:
Contact: Thomas Engel (thomas.engel@uni.lu), Andy Rupp (andy.rupp@uni.lu)