IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
17 August 2022
Christian Badertscher, Peter Gaži, Iñigo Querejeta-Azurmendi, Alexander Russell
ePrint ReportIn this work, towards understanding the general security of VRFs and in particular the ECVRF construction, we provide an ideal functionality in the Universal Composability (UC) framework (Canetti, FOCS'01) that captures VRF security, and show that ECVRF UC-realizes this functionality.
We further show how the range of a VRF can generically be extended in a modular fashion based on the above functionality. This observation is particularly useful for protocols such as Ouroboros since it allows to reduce the number of VRF evaluations (per slot) and VRF verifications (per block) from two to one at the price of additional (but much faster) hash-function evaluations.
Finally, we study batch verification in the context of VRFs. We provide a UC-functionality capturing a VRF with batch-verification capability, and propose modifications to ECVRF that allow for this feature. We again prove that our proposal UC-realizes the desired functionality. We provide a performance analysis showing that verification can yield a factor-two speedup for batches with 1024 proofs, at the cost of increasing the proof size from 80 to 128 bytes.
Kevin Lewi, Jon Millican, Ananth Raghunathan, Arnab Roy
ePrint ReportWe present a new primitive, called the Oblivious Revocable Function (ORF), which operates in the above setting and allows identifiers to be obliviously mapped to a consistent value across multiple devices, while enabling the server to permanently remove an individual device’s ability to map values. This permits a stronger threat model against metadata, in which metadata cannot be derived from identifiers by a revoked device colluding with the service provider, so long as the service provider was honest at the instant of revocation. We describe a simple Diffie- Hellman-based construction that achieves ORFs and provide a proof of security under the UC framework.
Sarah Arpin, Tyler Raven Billingsley, Daniel Rayor Hast, Jun Bo Lau, Ray Perlner, Angela Robinson
ePrint ReportDaniël Kuijsters, Denise Verbakel, Joan Daemen
ePrint ReportAlan Szepieniec, Frederik Vercauteren
ePrint ReportMichael Backes, Pascal Berrang, Lucjan Hanzlik, Ivan Pryvalov
ePrint ReportElection
Nominations are due by October 1st, 2022.
Information about the vacant positions and the nomination process is available at https://iacr.org/elections/2022/announcement.html.
16 August 2022
TU Eindhoven
Job PostingYou will conduct research at the intersection of quantum and post-quantum cryptography and publish/present the results at top venues for research in crypto/IT Security. This is a joint doctorate, supervised by A. Hülsing, K. Hövelmanns and B. Škorić.
You must meet the following requirements:
- Master’s degree or equivalent in computer science, mathematics, or a related field.
- Outstanding grades in classes related to cryptography, IT security, theoretical CS, or mathematics. (Familiarity with provable security and/or a strong mathematical background are a plus.)
- Excellent communication/writing skills in English. (No Dutch required.)
- Compliance with the MSCA-ITN mobility rule: You must not have resided or carried out your main activity (work, studies, etc.) in the Netherlands for more than 12 months in the 36 months immediately before your recruitment date.
- Full-time employment for the duration of the PhD (four years at TU/e).
- A well-rounded training offered by the QSI network, covering a range of topics related to secure communications in the quantum era, as well as complementary training intended to enhance your personal development.
- Generous travel budget that allows for, e.g., exposure to different sectors via planned placements and attendance to summer schools.
- Salary and benefits in accordance with the collective labour agreement for Dutch universities. Candidates from abroad can be eligible to an additional tax reduction scheme.
Closing date for applications:
Contact: To apply or for questions, use itn-applications@huelsing.net. Applications should contain (in a single PDF):
- Cover letter describing your research interests
- CV, including transcripts
- Contact details of 2-3 potential references
11 August 2022
Freie Universität Berlin, Department of Computer Science, Germany
Job PostingThe Cybersecurity and AI Group led by Prof. Gerhard Wunder (https://www.mi.fu-berlin.de/en/inf/groups/ag-comm/index.html/) and the Information Security Group led by Prof. Marian Margraf (https://www.mi.fu-berlin.de/inf/groups/ag-idm/index.html/) at Freie Universität Berlin are looking for one PhD student in the area of cryptographic security, post-quantum codes and signatures.
The position is connected to UltraSec, which is a research project focusing on the immensely potential Ultra Wide Band (UWB) wireless technology. The collaborative project consists of partners from leading academia, IoT and security centric startup, research institute, and industry. The PhD candidate contributes to the theoretical foundations, design, and implementation of security architecture for UWB based IoT-development platform thereby closely collaborating with the partners in the consortium. Candidates are expected to co-author articles published in high-quality academic venues such as IEEE/ACM conferences and journals. Within the framework of the externally funded research project, the opportunity for writing a doctoral-thesis is granted.
Your profile
- Applicants must possess a master degree in computer science, mathematics, electrical engineering or similar.
- Solid mathematical background in classical cryptography, post-quantum cryptography, and good coding skills in C/Go/Rust/Python/MATLAB is desirable.
- General understanding of coding quality and solid practice of source code and project management tools (Git, Travis-CI etc) is a plus.
- Moreover, the candidate should be able and willing to work and cooperate with the members of group and the project consortium.
Starting Date: October/ November 2022.
Further information can be found here: https://www.mi.fu-berlin.de/en/inf/groups/ag-comm/open-positions/wimis/index.html
Closing date for applications:
Contact: Applications including all the relevant documents should be sent electronically by e-mail to g.wunder@fu-berlin.de (cc: stefanie.bahe@fu-berlin.de), preferably as a single pdf-document.
More information: https://www.mi.fu-berlin.de/en/inf/groups/ag-comm/open-positions/wimis/index.html
Simula UiB, Bergen, Norway
Job Posting- Design and analysis of dedicated symmetric-key ciphers for privacy-preserving mechanisms (e.g. MPC, FHE, ZKP schemes); or,
- Quantum cryptanalysis of symmetric-key primitives.
We are looking for a candidate who has recently completed, or is about to complete, a master’s degree in cryptography, mathematics, or a closely related field. The master’s degree must have been awarded, with good results, before their start in the PhD position – in particular the candidate must satisfy the enrolment requirements for the PhD programme at the University of Bergen. The candidate must be highly motivated and be able to demonstrate their potential for conducting original research in cryptography. Simula UiB currently has 13 Early Career Researchers working on a range of research problems in cryptography and information theory and can offer a vibrant, stimulating and inclusive working environment to the successful candidate.
Interested and qualified candidates should apply at https://www.simula.no/about/job/phd-student-symmetric-key-cryptography
Deadline for application is 31 October 2022; however applications will be screened continuously, and we may conclude recruitment as soon as we find the right candidate. The starting date is negotiable.
Closing date for applications:
Contact: For additional enquiries about this position, please contact Carlos Cid (carlos@simula.no)
More information: https://www.simula.no/about/job/phd-student-symmetric-key-cryptography
University of St. Gallen
Job PostingMore specifically, the job includes:
- Development and implementation of concepts and research results, both individually and in collaboration with researchers and PhD students;
- Run of experiments and simulation of realistic conditions to test the performance of developed algorithms and protocols;
- Development, maintenance and organization of software;
- Support to BSc, MSc and PhD students, postdocs and researchers who use the lab;
- Responsibility for day routines in the lab, for example purchases, installations, bookings, inventory;
Your profile:
Closing date for applications:
Contact: Katerina Mitrokotsa
More information: https://jobs.unisg.ch/offene-stellen/cryptography-engineer-m-w-d/ccfd1b3a-e89c-4918-81e7-478348b0c48d
Technical University of Denmark
Job PostingWe are looking for a bright and motivated PhD student for a 3-year fully funded PhD position starting 1 November 2022 (negotiable). The project is financed by the Independent Research Fund Denmark, and it is a collaboration between DTU, the University of Cambridge, the University of Colorado, Colorado Springs, and Telenor Denmark. It is an excellent opportunity to be involved in advanced research on cyber-security, with important practical applications.
The project’s emphasis will be on digital ghost ships (DGS). A DGS is defined as any online resource (e.g. an IoT device) that has been connected to the Internet and has been subsequently abandoned (in terms of management, updates, or security patches). Hence, DGS may include systems with default usernames and passwords as well as systems that lack important security updates. We aim at proposing novel ways for identifying such DGS, which is the first step into making them secure or taking them down. To do this, the project will not only research novel network detection techniques but also examine how human psychology plays a role in creating DGS.
Closing date for applications:
Contact: Emmanouil Vasilomanolakis
More information: https://www.compute.dtu.dk/english/sitecore/indhold/dtu/dtuenglish-old/forside/about/job-and-career/vacant%20positions/job?id=5ffc257d-616c-4f97-b39d-d16d483459c3
CWI Amsterdam, Computer Security Group
Job PostingThe Ph.D. will focus on discovering new security threats introduced by cloud FPGAs and developing new secure architectures to safeguard cloud infrastructures and their users. A secure deployment strategy of cloud FPGAs will be developed; it should cover all known security threats and new security threats discovered during the project. The overall research project will be conducted on both local experimental setups and online real-world FPGA-integrated cloud environments.
Requirements: PhD candidates are required to have a master degree in computer science, mathematics, electrical engineering, or comparable areas. Candidates that are expected to finish their M.Sc. thesis in the near future can also apply. Candidates should have a clear interest in fundamental research, should be creative and solid in their research, should have (potential) interest in computer security and computer engineering, and should be able to cooperate with experts from different disciplines. It is essential that you have good academic writing and presentation skills. Candidates are expected to have an excellent command of English.
Information and application: The application deadline is 31 August 2022. All applications should include a motivation letter, a detailed CV, and a list of grades and courses.
Interested candidate can learn more information at https://www.cwi.nl/jobs/vacancies/946698
Closing date for applications:
Contact: Dr. Chenglu Jin, chenglu.jin@cwi.nl
More information: https://www.cwi.nl/jobs/vacancies/946698
SINTEF Digital, Trondheim, Norway
Job PostingClosing date for applications:
Contact: Per Håkon Meland
More information: https://candidate.hr-manager.net/ApplicationInit.aspx?cid=1131&ProjectId=145153&DepartmentId=18961&MediaId=5
Ari Karchmer
ePrint ReportDamien Robert
ePrint ReportDonghang Lu, Aniket Kate
ePrint ReportCecilia Boschini, Akira Takahashi, Mehdi Tibouchi
ePrint ReportIn this paper, we introduce MuSigL, a lattice-based multi-signature scheme simultaneously achieving these design goals for the first time. Unlike the recent, round-efficient proposal of Damgård et al. (PKC'21), which had to rely on lattice-based trapdoor commitments, we do not require any additional primitive in the protocol, while being able to prove security from the standard module-SIS and LWE assumptions. The resulting output signature of our scheme therefore looks closer to the usual Fiat--Shamir-with-abort signatures.
Elette Boyle, Geoffroy Couteau, Niv Gilboa, Yuval Ishai, Lisa Kohl, Peter Scholl
ePrint ReportIn this work, we design a new class of efficient PCGs based on different flavors of the ring-LPN assumption. Our new PCGs can generate OLE correlations, authenticated multiplication triples, matrix product correlations, and other types of useful correlations over large fields. These PCGs are more efficient by orders of magnitude than the previous constructions and can be used to improve the preprocessing phase of many existing MPC protocols.
Kai Hu, Thomas Peyrin, Meiqin Wang
ePrint ReportIn this paper, we propose a systematic method to find all IDs for SPN block ciphers. The idea is to partition the whole difference pair space into lots of small disjoint sets, each of which has a representative difference pair. All difference pairs in one small set are possible if its representative pair is possible, and this can be conveniently checked by the MILP model. In this way, the overall search space is drastically reduced to a practical size by excluding the sets containing no IDs. We then examine the remaining difference pairs to identify all IDs (if some IDs exist). If our method cannot find any ID, the target cipher is proved free of ID distinguishers.
Our method works especially well for SPN ciphers with block size 64. We apply our method to SKINNY-64 and successfully find all 432 and 12 truncated IDs (we find all IDs but all of them can be assembled into certain truncated IDs) for 11 and 12 rounds, respectively. We also prove, for the first time, that 13-round SKINNY-64 is free of ID distinguishers even when considering the differential transitions through the Difference Distribution Table (DDT). Similarly, we find all 12 truncated IDs (all IDs are assembled into 12 truncated IDs) for 13-round CRAFT and prove there is no ID for 14 rounds. For SbPN cipher GIFT-64, we prove that there is no ID for 8 rounds.
For SPN ciphers with larger block sizes, we show that our idea is also useful to strengthen the current search methods. For example, if we consider the Sbox to be ideal and only consider the branch number information of the diffusion matrix, we can find all 6,750 truncated IDs for 6-round Rijndael-192 in 1 second and prove that there is no truncated ID for 7 rounds. Previously, we need to solve approximately $2^{48}$ MILP models to achieve the same goal. For GIFT-128, we exhausted all difference patterns that have an active superbox in the plaintext and ciphertext and proved there is no ID of such patterns for 8 rounds.
Although we have searched for a larger or even full space for IDs, no longer ID distinguishers have been found. This implies the reasonableness of the intuition that a small number (usually one or two) of active bits/words at the beginning and end of an ID will be the longest.