International Association
for Cryptologic Research

This work considers two prominent key management problems in the blockchain space: (i) allowing a (distributed) blockchain system to securely airdrop/send some tokens to a potential client Bob, who is yet to set up the required cryptographic key for the system, and (ii) creating a (distributed) cross-chain bridge that allows interoperability at scale by allowing a (changing) set of nodes in a blockchain to perform transactions on the other blockchain. The existing solutions for the first problem need Bob to either generate and maintain private keys locally for the first time in his life — a usability bottleneck — or place trust in third-party custodial services — a privacy and censorship nightmare. Towards solving both problems in a distributed setting against a threshold-bounded adversary, distributed key generation (DKG) based solutions are actively employed; here, a set of servers generate the transactions in a distributed manner and link them to clients’ ids. Nevertheless, these solutions introduce computation and communication overhead that is linear in the number of keys and do not scale well even for a million keys, especially for proactive security against a mobile adversary. This work presents a Keys-On-Demand (D-KODE) distributed protocol suite that lets the blockchain system securely generate the public key of any Bob against a mobile threshold adversary. Multiple servers, here, compute discrete-log private/public keys on the fly through distributed pseudo-random function evaluations on the queried public string. D-KODE also introduces a proactive security mechanism for the employed black-box secret-sharing based DKG to maintain the system’s longitudinal security. The proposed protocol scales well for a very high number of keys as its communication and computation complexity is independent of the number of keys. Our experimental analysis demonstrates that, for a 20-node network with a 2/3 honest majority, D-KODE starts to outperform the state of the art as the number of keys reaches 94K. D-KODE is practical as it takes less than 100msec to generate a secret key for a single-threaded server in a 20-node setup

The Institute of Information Security and Dependability at KIT is looking for two PostDocs in privacy-preserving cryptographic protocols. Experiences with secure multi-party computation and MPC compilers or UC-based security modeling are desired. A track record in this field is expected, including publications at reputable conferences such as Crypto, Eurocrypt, ACM CCS, PETS, etc.

You will be a member of the KASTEL Security Research Labs (https://zentrum.kastel.kit.edu) and the Topic "Engineering Secure Systems" of the Helmholtz Association. Your research is dealing with cryptographic protocols for privacy-preserving computations, e.g., applied to mobility or production systems. It will result in both theoretical security concepts (protocol designs, security proofs, etc.) and their practical implementation (e.g., a demonstrator) for some application domain. The contract will initially be limited to 1 year, but can be extended.

If you are interested, please send an email including your CV and a list of publications to andy.rupp@rub.de. Applications will be reviewed continuously until the positions are filled.

Closing date for applications:

Contact: Andy Rupp (andy.rupp@rub.de)

You will join the team responsible for the security architecture of Qualcomm Snapdragon processors. The team works at a system level spanning across hardware, software and infrastructure while striving for industry-leading solutions. This team interacts with product management, customers (e.g., OEMs), partners and HW/SW engineering teams to find the optimal security solutions.
Snapdragon processors are used in different types of devices ranging from mobile phones to televisions, cars, ultra-book laptops etc. Our processors are designed to meet security requirements ranging from content protection to enterprise security, using virtualization, HW security enclaves, factory key provisioning, and secure updates.
In this position you will perform the following tasks:

• Define HW crypto security requirements (functional, performance, security etc)
• Define HW/SW partitioning to address next challenges in cryptography such as PQC and Crypto Agility
• Define crypto and HW blocks that contribute to the overall SoC Security Architecture
• Design of mechanisms thwarting side channel attacks
• Monitor evaluation of crypto IP resistance and robustness
• Competitive analysis of security IPs and features
• Investigate future/roadmap security related technologies,
• Participation in academic conference and industrial/research security working groups.

Minimum Qualifications: MS or Bachelor in Computer Science, Mathematics or Electrical Engineering plus 5+ years industry experience in one or more of the following areas

• Cryptographic primitives, cryptographic protocols and their implementation
• Design of HW/SW security blocks such as HW cryptographic engines
• HW/SW threat analysis, security analysis or/and risk analysis
• Smart Card and secure HW technologies
• Security certifications: process and requirements.

Additional skills in the following areas are a plus:

• Academic and industry research (publications, conferences)
• Leadership & management background
• Excellent communication and teamwork skills are required

Closing date for applications:

Contact: Nicolas Courtois

More information: https://qualcomm.wd5.myworkdayjobs.com/en-US/External/details/Embedded-Crypto-Expert---Sophia-Antipolis--France_3024348-1?locationCountry=54c5b6971ffb4bf0b116fe7651ec789a

Event date: 26 July to 28 July 2022
Submission deadline: 15 March 2022
Notification: 25 May 2022

Event date: 10 July to 16 July 2022
Submission deadline: 1 April 2022
Notification: 15 May 2022

Event date: 31 August to 2 September 2022
Submission deadline: 26 March 2022
Notification: 30 May 2022

Your Challenge Help bring research to life and drive your career forward with the National Research Council of Canada (NRC), Canada's largest research and technology organization. We are looking for an early-career Research Associate to support our Digital Technologies research centre (DT). The Research Associate would be someone who shares our core values of Integrity, Excellence, Respect and Creativity. Help bring research to life and drive your career forward with the National Research Council of Canada (NRC), Canada's largest research and technology organization. Working with the NRC is an exciting opportunity to pursue a research career both independently and with a dynamic research team. We are looking for a Research Associate to join NRC’s Digital Technologies Research Centre (NRC-DT). The Digital Technologies Research Centre collects multiple research teams who focus on machine learning, advanced analytics, computer vision, bioinformatics, cyber security, natural language processing, quantum computing and other branches of digital technologies and artificial intelligence. The primary responsibility of the researcher in this position is to support the goals of NRC and the activities of the Digital Technologies Research Centre in conducting research of international calibre in applied quantum computing, including quantum algorithms and software, quantum error correction, theoretical models of quantum computing and other related areas. The researcher will work in a team environment with other researchers and technical experts in world-class facilities. The researcher will participate in the development and execution of an original research agenda in collaboration with NRC colleagues and with academic and commercial partners across Canada. The researcher will be called upon to contribute to collaborative research projects in support of NRC’s Applied Quantum Computing challenge program.

Closing date for applications:

Contact: Human Resources at: NRC.NRCHiring-EmbaucheCNRC.CNRC@nrc-cnrc.gc.ca

More information: https://recruitment-recrutement.nrc-cnrc.gc.ca/job-invite/15641

The Cryptanalysis Taskforce at Nanyang Technological University in Singapore led by Prof. Jian Guo is seeking for candidates to fill several post-doctoral research fellow positions on symmetric-key cryptography. Topics include but are not limited to the following sub-areas:

• tool aided cryptanalysis, such as MILP, CP, STP, and SAT
• machine learning aided cryptanalysis and designs
• privacy-preserving friendly symmetric-key designs
• quantum cryptanalysis
• provable security
• cryptanalysis against SHA-2, SHA-3, and AES
• threshold cryptography

Established in 2014, the Cryptanalysis Taskforce is a group with about ten members currently dedicated for research in symmetric-key cryptography. Since establishment, the team has been active in both publications in and services for IACR. It has done quite some cryptanalysis work on various important targets such as SHA-3 and AES, and is expanding its interests to the areas mentioned above, with strong funding support from the university, industry partners, and government agencies in Singapore. We offer globally competitive salary package with extremely low tax (around 5%), as well as excellent environment dedicating for top-venues publication orientated research in Singapore. The contract will be initially for one year, and has the possibility to be extended. Candidates are expected to have proven record of publications in IACR conferences (Asiacrypt, Crypto, Eurocrypt). Interested candidates are to send their CV and 2 reference letters to Jian Guo. Review of applicants will start immediately until the positions are filled. More information about the Cryptanalysis Taskforce research group can be found via https://team.crypto.sg

Closing date for applications:

Contact: Jian Guo, guojian@ntu.edu.sg, with subject [IACR-CATF]

More information: https://team.crypto.sg

We are looking for a Postdoc fellow in the area of security of wireless IoT networks.
The project is jointly conducted between Mohammed VI Polytechnic University, Morocco, and EPFL Switzerland.
To apply, please send your cv with your list of publications.

Closing date for applications:

Contact: Mehdi Amhoud, email : elmehdi.amhoud(at)um6p.ma

About Protocol Labs Protocol Labs drives breakthroughs in computing to push humanity forward. Protocol Labs is a product-development lab, but behind the protocols and tools we build, behind the research and implementations, are passionate people, teammates and community members. We are a fully distributed company. Our team of more than 150 members works remotely and in the open to improve the internet — humanity's most important technology — as we explore new advances at the intersection of many exciting fields (crypto, networks, distributed systems) and cultures (startups, research, open source, distributed work). Seeking an experienced cryptographer to help us research and develop state of the art cryptosystems to upgrade the internet. Research at Protocol Labs This isn't an ordinary Research Scientist position. Your expertise is mostly driven by both a hunger to learn and a need to work toward solving important problems. Our research scientists are granted both the freedom to develop their knowledge by working on novel applications, and a responsibility to contribute those skills toward advancing the flagship projects of Protocol Labs. You’ll feel at home working with us if your knowledge and optimism enables you to name a few unusual possible approaches when you’re first presented with a problem that people often consider intractable. We see cryptography often acting as the last line of defense in a world that’s rife with malicious actors. We examine a broad spectrum of potential projects, like Filecoin, that rely on providing various cryptographic guarantees to users. Achieving these guarantees in practice often requires drawing from or advancing the frontiers of cryptographic protocols. As a result, we seek cryptographers who can discover, conceive, incorporate, and implement new techniques.

Closing date for applications:

Contact: Apply here- https://boards.greenhouse.io/protocollabs/jobs/4283969004

More information: https://boards.greenhouse.io/protocollabs/jobs/4283969004

The submission deadline for CRYPTO 2022 is 16 February 2022 (AoE) and the submission server is now open.

Instructions for authors and the link to submission server can be found here https://crypto.iacr.org/2022/papersubmission.php.

We describe a straightforward method to generate a random prime q such that the multiplicative group GF(q)* also has a random large prime-order subgroup. The described algorithm also yields this order p as well as a p'th primitive root of unity. The methods here are efficient asymptotically, but due to large constants may not be very useful in practical settings.

The past couple of decades witnessed a tremendous expansion in the IoT world that gathers now billions of devices, sensors, users and transactions. The aspirations of ubiquitous computing have changed the computing world drastically, from a parallel point of view, to distributed, then grid and cloud computing – all these just to keep up with the proliferation of devices and the users’ expectations. Alongside with this fast development, many issues appeared, especially in terms of scalability and security. Regardless of protocol, device, applications or technologies used, there will be critical data involved and, therefore, vulnerabilities that can affect the performance of the system or be exploited maliciously. The higher the number of devices, the more constraints appear and along with these constraints the existing models and technologies become overwhelmed and simply not enough. The size of the IoT and its autonomous character make it impossible to sustain and implement a centralized authentication system. Therefore, to allow reliable peer authentication and to approach a trust level management, we propose discussing a model based on blockchain technology. Blockchain is a revolutionary technology, modeled by a linear sequence of blocks, considered to be the future of wireless networks security. We rely on this new data structure to address two major components of security in mobile networks: authentication and trust.

The performance of higher-order masked implementations of lattice-based based key encapsulation mechanisms (KEM) is currently limited by the costly conversions between arithmetic and boolean masking. While bitslicing has been shown strongly speed up to masked implementations of symmetric primitives, it has never been used in higher-order arithmetic-to-boolean and boolean-to-arithmetic masking conversion gadgets. In this paper, we first show that bitslicing can indeed accelerate existing conversion gadgets. We then optimize these gadgets, exploiting the degrees of freedom offered by bitsliced implementations. As a result, we introduce new arbitrary-order boolean masked addition, arithmetic-to-boolean and boolean-to-arithmetic masking conversion gadgets, each in two variants: modulo \(2^k\) and modulo \(p\) (for any integers \(k\) and \(p\)). Practically, our new gadgets achieve a speedup of up to 25x over the state of the art. Turning to the KEM application, we develop the first open-source embedded (Cortex-M4) implementations of Kyber768 and Saber masked at arbitrary order. The implementations based on the new bitsliced gadgets achieve a speedup of 1.8x for Kyber and 3x for Saber, compared to the implementation based on state of the art gadgets. The bottleneck of the bitslice implementations is the masked Keccak-f[1600] permutation.

Private Set Union ($\mathsf{PSU}$) allows two players, the sender and the receiver, to compute the union of their input datasets without revealing any more information than the result. While it has found numerous applications in practice, not much research has been carried out so far, especially for large datasets.

In this work, we take shuffling technique as a key to design $\mathsf{PSU}$ protocols for the first time. By shuffling receiver's set, we put forward the first protocol, denoted as $\Pi_{\mathsf{PSU}}^{\mathsf{receiver}}$, that eliminates the expensive operations in previous works, such as additive homomorphic encryption and repeated operations on the receiver's set. It outperforms the state-of-the-art design by Kolesnikov et al. (ASIACRYPT 2019) in both efficiency and security; the unnecessary leakage in Kolesnikov et al.'s design, can be avoided in our design.

We further extend our investigation to the application scenarios in which both players may hold unbalanced input datasets. We propose our second protocol $\Pi_{\mathsf{PSU}}^{\mathsf{sender}}$, by shuffling the sender's dataset. This design can be viewed as a dual version of our first protocol, and it is suitable in the cases where the sender's input size is much smaller than the receiver's.

Finally, we implement our protocols $\Pi_{\mathsf{PSU}}^{\mathsf{receiver}}$ and $\Pi_{\mathsf{PSU}}^{\mathsf{sender}}$ in C++ on big datasets, and perform a comprehensive evaluation in terms of both scalability and parallelizability. The results demonstrate that our design can obtain a $4$-$5 \times$ improvement over the state-of-the-art by Kolesnikov et al. with a single thread in WAN/LAN settings.

We define a framework for analyzing the security of cryptographic protocols that makes minimal assumptions about what a "realistic model of computation is". In particular, whereas classical models assume that the attacker is a (perhaps non-uniform) probabilistic polynomial-time algorithm, and more recent definitional approaches also consider quantum polynomial-time algorithms, we consider an approach that is more agnostic to what computational model is physically realizable.

Our notion of cosmic security considers a reduction-based notion of security that models attackers as arbitrary unbounded stateful algorithms; we also consider a more relaxed notion of cosmic security w.r.t. weakly-restartable adversaries which makes additional restrictions on the attacker’s behavior. We present both impossibility results and general feasibility results for our notions, indicating that extended Church-Turing hypotheses may not be needed for a well-founded theory of Cryptography.

An idealised decentralised exchange (DEX) provides a medium in which players wishing to exchange one token for another can interact with other such players and liquidity providers at a price which reflects the true exchange rate, without the need for a trusted third-party. Unfortunately, extractable value is an inherent flaw in existing blockchain-based DEX implementations. This extractable value takes the form of monetizable opportunities that allow blockchain participants to extract money from a DEX without adding demand or liquidity to the DEX, the two functions for which DEXs are intended. This money is taken directly from the intended DEX participants. As a result, the cost of participation in existing DEXs is much larger than the upfront fees required to post a transaction on a blockchain and/or into a smart contract. We present FairTraDEX, a decentralised variant of a frequent batch auction (FBA), a DEX protocol which provides formal game-theoretic guarantees against extractable value. FBAs when run by a trusted third-party provide unique game-theoretic optimal strategies which ensure players are shown prices equal to the liquidity provider's fair price, excluding explicit, pre-determined fees. FairTraDEX replicates the key features of an FBA that provide these game-theoretic guarantees using a combination of set-membership in zero-knowledge protocols and an escrow-enforced commit-reveal protocol. We extend the results of FBAs to handle monopolistic and/or malicious liquidity providers, and provide a detailed pseudo-code implementation of FairTraDEX based on existing mainstream blockchain protocols.

Given a private string q and a remote server that holds a set of public documents D, how can one of the K most relevant documents to q in D be selected and viewed without anyone (not even the server) learning anything about q or the document? This is the oblivious document ranking and retrieval problem. In this paper, we describe Coeus, a system that solves this problem. At a high level, Coeus composes two cryptographic primitives: secure matrix-vector product for scoring document relevance using the widely-used term frequency-inverse document frequency (tf-idf) method, and private information retrieval (PIR) for obliviously retrieving documents. However, Coeus reduces the time to run these protocols, thereby improving the user-perceived latency, which is a key performance metric. Coeus first reduces the PIR overhead by separating out private metadata retrieval from document retrieval, and it then scales secure matrix-vector product to tf-idf matrices with several hundred billion elements through a series of novel cryptographic refinements. For a corpus of English Wikipedia containing 5 million documents, a keyword dictionary with 64K keywords, and on a cluster of 143 machines on AWS, Coeus enables a user to obliviously rank and retrieve a document in 3.9 seconds---a 24x improvement over a baseline system.

In SIDH and SIKE protocols, public keys are defined over quadratic extensions of prime fields. We present in this work a projective invariant property characterizing affine Montgomery curves defined over prime fields. We then force a secret 3-isogeny chain to repeatedly pass through a curve defined over a prime field in order to exploit the new property and inject zeros in the A-coefficient of an intermediate curve to successfully recover the isogeny chain one step at a time. Our results introduce a new kind of fault attacks applicable to SIDH and SIKE.

Hash-Based Signature (HBS) uses a hash function to construct a digital signature scheme, where its security is guaranteed by the collision resistance of the hash function used. To provide sufficient security in the post-quantum environment, the length of hash should be satisfied. Modern HBS can be classified into stateful and stateless schemes. Two representative stateful and stateless HBS are XMSS and SPHINCS$^+$, respectively. In this paper, we propose two HBS schemes: K-XMSS and K-SPHINCS$^+$, which replace internal hash functions of XMSS and SPHINCS$^+$ with Korean cryptography algorithms. K-XMSS is a stateful signature, while K-SPHINCS$^+$ is its stateless counterpart. We also showcase the reference implementation of K-XMSS and K-SPHINCS$^+$ employing LSH and two hash functions based on block ciphers (i.e. CHAM and LEA) as the internal hash function. The reference code is developed as a proof-of-concept, which can be optimized for better performance using advanced implementation techniques (e.g. AVX2 and NEON).