IACR News
Here you can see all recent updates to the IACR webpage. These updates are also available:
17 August 2022
Ananya Appan, Anirudh Chandramouli, Ashish Choudhury
To design our protocol, we present two important building blocks which are of independent interest. The first building block is a best-of-both-worlds perfectly-secure Byzantine agreement (BA) protocol for $Q^{(3)}$ adversary structures, which remains secure both in a synchronous, as well as an asynchronous network. The second building block is a best-of-both-worlds perfectly-secure verifiable secret-sharing (VSS) protocol, which remains secure against $Q^{(3)}$ and $Q^{(4)}$ adversary structures in a synchronous network and an asynchronous network respectively.
Joël Alwen, Dominik Hartmann, Eike Kiltz, Marta Mularczyk, Peter Schwabe
In this work we describe a collection of new results around batched KEMs and PKE. We provide both classic and post-quantum proofs for all results. Our results are geared towards practical constructions and applications (for example in the domain of PQ-secure group messaging).
Concretely, our results include a new non-adaptive to adaptive compiler for CPA-secure mKEMs resulting in public keys roughly half the size of the previous state-of-the-art [Hashimoto et.al., CCS'21]. We also prove their FO transform for mKEMs to be secure in the quantum random oracle model. We provide the first mKEM combiner as well as two mmPKE constructions. The first is an arbitrary message-length black-box construction from an mKEM (e.g. one produced by combining a PQ with a classic mKEM). The second is optimized for short messages and achieves hybrid PQ/classic security more directly. When encrypting $n$ short messages (e.g. as in several recent mmPKE applications) at 256-bits of security the mmPKE ciphertext are $144 n$ bytes shorter than the generic construction. Finally, we provide an optimized implementation of the (CCA secure) mKEM construction based on the NIST PQC winner Kyber and report benchmarks showing a significant speedup for batched encapsulation and up to 79% savings in ciphertext size compared to a naive solution.
Christian Badertscher, Peter Gaži, Iñigo Querejeta-Azurmendi, Alexander Russell
In 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
We 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
Daniël Kuijsters, Denise Verbakel, Joan Daemen
Alan Szepieniec, Frederik Vercauteren
Michael Backes, Pascal Berrang, Lucjan Hanzlik, Ivan Pryvalov
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
You 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
The 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
- 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
More 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
We 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
The 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
Closing 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
Damien Robert
Donghang Lu, Aniket Kate
Cecilia Boschini, Akira Takahashi, Mehdi Tibouchi
In 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.