IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
26 August 2020
Christian Badertscher, Peter Gazi, Aggelos Kiayias, Alexander Russell, Vassilis Zikas
ePrint ReportIn this work we give the first thorough treatment of self-healing properties of distributed ledgers covering both proof-of-work (PoW) and proof-of-stake (PoS) protocols. Our results quantify the vulnerability period that corresponds to an adversarial spike and classify three types of currently deployed protocols with respect to their self-healing ability: PoW-based blockchains, PoS-based blockchains, and iterated Byzantine Fault Tolerant (iBFT) protocols.
Katharina Boudgoust, Corentin Jeudy, Adeline Roux-Langlois, Weiqiang Wen
ePrint ReportViet Tung Hoang, Yaobin Shen
ePrint ReportGrand Anse, Grenada, 1 March - 5 March 2021
Event CalendarSubmission deadline: 17 September 2020
Notification: 3 December 2020
Institute of Science and Technology Austria
Job PostingThe Institute of Science and Technology Austria invites applications for several open positions in all areas of computer science including cryptography, systems security and privacy.
IST Austria offers:
- A highly international and interdisciplinary research environment with English as working language on campus
- State-of the art facilities and scientific support services (www.ist.ac.at/scientific-service-units/)
- Competitive start-up package and salary
- Guaranteed annual base funding including funding for PhD students and postdocs
- Wide portfolio of career support
- Child-care facilities and support on campus
IST Austria is an international institute dedicated to basic research and graduate education in the natural, mathematical, and computational sciences. The Institute fosters an interactive, collegial, and supportive atmosphere, sharing space and resources between research groups whenever possible, and facilitating cross-disciplinary collaborations. Our PhD program involves a multi-disciplinary course schedule and rotations in research groups and hire scholars from diverse international backgrounds. The campus of IST Austria is located close to Vienna, one of the most livable cities in the world.
Assistant professors receive independent group leader positions with an initial contract of six years, at the end of which they are reviewed by international peers. If the evaluation is positive, an assistant professor is promoted to a tenured professor.
Candidates for tenured positions are distinguished scientists in their respective research fields and have at least six years of experience in leading a research group.
Please apply online at: www.ist.ac.at/jobs/faculty
The closing date for applications is October 30, 2020.
IST Austria values diversity and is committed to equal opportunity. We strive for increasing the number of women, particularly in fields where they are underrepresented, and therefore we strongly encourage female researchers to apply.
Closing date for applications:
Contact: krzysztof.pietrzak@ist.ac.at
More information: https://ist.ac.at/en/jobs/faculty/
Apheris | Deep tech company for privacy-preserving data ecosystems in Berlin, Germany
Job PostingWe are looking for an Expert in Cryptography and/or Privacy-Preserving Computations with the right skillset to complement our team with practical deep tech and coding expertise.
Join us putting cutting-edge privacy-preserving technologies and federated computations into production.
As a domain Expert in Cryptography, you will help us build never-seen-before deep tech products for our high-profile customers. You contribute to the Apheris products, including protocol and architecture and author detailed technical concepts around cryptography. You identify and resolve performance bottlenecks and perform and participate in code reviews. Together with our CTO and other senior engineers you will help us hit product milestones by writing high quality, well tested code.
Closing date for applications:
Contact: Robin Röhm, career@apheris.com
More information: https://apheris-jobs.personio.de/job/242412
25 August 2020
Max Planck Institute for Security and Privacy
Job Posting
In order to be considered for the position, the candidate must:
The MPI for Security and Privacy is co-located with the Ruhr University of Bochum (Germany) and offers a vibrant atmosphere for research that spans across all aspects of computer security. The knowledge of German is not required for a successful career at MPI. To apply for the position, send an email to Giulio Malavolta (address below) including the following documents:
If you have any questions, don’t hesitate to get in touch.
Closing date for applications:
Contact: Giulio Malavolta (giulio.malavolta@hotmail.it)
24 August 2020
University of St. Gallen, Switzerland
Job PostingResearch area: Research areas include but are not limited to:
- Verifiable computation
- Secure Multi Party Computation
- Privacy-preserving authentication
- Cryptographic primitives
- A MsC degree in Computer Science, Applied Mathematics or a relevant field;
- Strong mathematical and algorithmic CS background;
- Good skills in programming is beneficial;
- Excellent written and verbal communication skills in English
Starting date: Fall 2020 or by mutual agreement
Contact: Prof. Katerina Mitrokotsa
Closing date for applications:
Contact: Katerina Mitrokotsa
More information: http://direktlink.prospective.ch/?view=2d5b5bd0-e017-4917-90bb-14f3b6efe9c4
Kolkata, India, 2 March - 5 March 2021
Event CalendarSubmission deadline: 30 November 2020
Notification: 30 December 2020
23 August 2020
Steven D. Galbraith, Trey Li
ePrint ReportLet n in N be the bit length, t in N be the threshold indicating big/small, x in {0,1}^n be the characteristic vector of a set, with its hamming weight |x| denoting the size of the set. Our obfuscation for x requires that ||x|-t| < n/2. Note that a random x has hamming weight approximately n/2, hence this condition is for free most of the time.
Our obfuscation requires hamming distance evasiveness, which is stronger than big subset and small superset evasiveness. Though, this requirement already implies a fairly large family of functions to obfuscate.
We also give a proof of input-hiding for the conjunction obfuscation by Bartusek et al. [5] (see Appendix A) and propose a new conjunction obfuscation based on the big subset and small superset obfuscation (see Appendix B). The security of our conjunction obfuscation is from our new assumption called the twin subset product problem.
22 August 2020
Andrey Sobol, Anastasiia Kondaurova
ePrint ReportAbhishek Chakraborty, Ankit Mondal, Ankur Srivastava
ePrint ReportVasyl Ustimenko
ePrint ReportYuntao Liu, Ankur Srivastava
ePrint ReportShou-Ching Hsiao, Zi-Yuan Liu, Raylin Tso
ePrint ReportYi-Fu Lai, Steven D. Galbraith, Cyprien Delpech de Saint Guilhem
ePrint ReportIn this work, we propose the first isogeny-based UC-secure oblivious transfer protocol in the presence of malicious adversaries without analogues in the Diffie-Hellman setting. The simple and compact CSIDH-based scheme consists of a constant number of isogeny computations. The underlying relaxed problem is called the computational reciprocal CSIDH problem which we can prove equivalent to the computational CSIDH problem with a quantum reduction.
Tancrède Lepoint, Sarvar Patel, Mariana Raykova, Karn Seth, Ni Trieu
ePrint ReportWe introduce the notion of private information retrieval (PIR) with default, which enables two-party PJC functionalities in a way that hides the size of the intersection of the two databases and incurs sublinear communication cost in the size of the bigger database. We provide two constructions for this functionality, one of which requires offline linear communication, which can be amortized across queries, and one that provides sublinear cost for each query but relies on more computationally expensive tools. We construct inner-product PJC, which has applications to ads conversion measurement and contact tracing, relying on an extension of PIR with default. We evaluate the efficiency of our constructions, which can enable $\mathbf{2^{12}}$ PIR with default lookups on a database of size $\mathbf{2^{30}}$ (or inner-product PJC on databases with such sizes) with the communication of $\mathbf{945}$MB, which costs less than $\mathbf{\$0.04}$ for the client and $\mathbf{\$5.22}$ for the server.
Romain Gay, Rafael Pass
ePrint ReportMore precisely, the circular security conjecture states that a notion of leakage-resilient security (which we refer to as shielded randomness leakage security) satisfied by GSW (assuming LWE) is retained in the presence of a key-cycle w.r.t. GSW and DJ.
Our work thus places iO on qualitatively similar assumptions as (unlevelled) FHE, for which known constructions also rely on a circular security conjecture.