International Association
for Cryptologic Research

Primitives enabling homomorphic computation over secret-shared values--Homomorphic Secret Sharing (HSS) and algebraic Homomorphic MACs (aHMAC)--have recently emerged as efficient alternatives to ciphertext-based primitives such as fully homomorphic encryption (FHE) and attribute-based encryption (ABE). Leveraging the distributed nature of secret sharing, direct constructions of HSS and aHMAC are simple, lightweight, avoid costly bootstrapping, and have many applications including one-bit-per-gate garbled circuits.

Despite encouraging progress, all existing direct schemes still lack one key feature: efficient Single Instruction Multiple Data (SIMD) evaluation, a capability that has been critical to the efficiency of FHE. This gap leaves the potential of substantial efficiency improvements untapped.

We present the first SIMD evaluation techniques for HSS and aHMAC, based on variants of the RLWE assumption. Using a new interval coefficient encoding, our approach embeds $\sqrt{n}$ integer-valued slots per ring element and supports $\sqrt{n}$-fold batch addition and multiplication in just $O(\log n)$ ring operations, achieving a multiplicative $\tilde O(\sqrt{n})$ improvement in amortized efficiency over prior direct constructions. Building on top of these improvements, we show a streamlined one-bit-per-gate SIMD garbling scheme with similar efficiency gains in the online phase.

Our efficiency gains are concrete. Concrete operation counts and microbenchmark based estimates show $6\times$--$10\times$ improvements in amortized multiplication cost over prior non-SIMD constructions, with up to $25\times$--$50\times$ speedups for aggregation-heavy workloads such as matrix--vector multiplication. These results demonstrate the practical potential of SIMD techniques for secret-sharing-based homomorphic computation.

Event date: 23 June to 26 June 2026
Submission deadline: 31 March 2026
Notification: 15 April 2026

Seagate Technology is a global leader in data storage. We design and manufacture the next generation of hard drives, offering high-performance, sustainable options with the capacity to support a massively expanding demand for data. Our Data Trust research vector is a global team of scientists focused on innovative ways to protect data privacy, reliability, and verifiability for current and future customers.

We’re seeking a research intern with interests in cryptography, systems security, or related areas of computer science. Alongside our cryptographic and systems security researchers, you'll do a deep dive into the development and analysis of emerging security tech. We carefully design our projects to help each intern best utilize their individual expertise, develop new skills, and simultaneously progress towards their scientific goals and Seagate's. You’ll work on an interdisciplinary team of engaging researchers, discuss the future of data handling with engineers across the company, and develop connections with our local and global networks that will last beyond the initial internship period.

In this role, you will:

• Perform fundamental research in data security and write peer-reviewed scientific papers

• Create formal analyses, new algorithm designs, or prototype implementations that advance the field of data security.

• Learn about and contribute to an understudied but fundamental pillar of the Internet, AI, and data science fields.

• Join an exciting cohort of students in a wide array of fields, including computer science, chemical & mechanical engineering, and biology

Our desired intern candidate is

• A current MS or PhD student in computer science or a closely related subject

• Familiar with principles of cryptography and systems security

• Experienced programming skills using one or more languages such as Rust, Go, C, C++, or Python.

• Able to work and communicate effectively with a diverse group of people

• Knowledgeable about formal verification, theorem provers, or provable security analysis

Closing date for applications:

Contact: Hannah Davis

More information: https://seagatecareers.com/job/Shakopee-Research-Intern-Security-and-Cryptography-MN/1343136000/

The School of Computing at the University of Kent invites applications for 3 fully-funded 3.5-year PhD (GTA) scholarships for UK students. You can apply to study for a PhD in any topic that falls within our range of expertise. Alongside completing your PhD programme of research and development, as a Graduate Teaching Assistant (GTA) you will normally be expected to work for 200 hours per annum in years 1 to 3, including teaching (maximum 96 contact hours per year) or demonstrating (maximum 130 contact hours per year) and related duties such as marking, preparation and examination. For preliminary discussions to work on cryptology-related topics, please contact Sanjay Bhattacherjee ([email protected]). More general enquiries should be directed to the PGR Admissions team ([email protected]). Details here: https://www.kent.ac.uk/scholarships/search/FN15COMPGR01

Closing date for applications:

Contact: Sanjay Bhattacherjee ([email protected])

More information: https://www.kent.ac.uk/scholarships/search/FN15COMPGR01

Event date: 21 May to 22 May 2026

Event date: 21 September to 25 September 2026

Event date: 10 May to

PhD Studentship in Cryptography

Applications are invited for a PhD studentship in Cryptography within the Information Security Group (https://cryptography.isg.rhul.ac.uk/) at Royal Holloway, University of London.

The studentship is available for a start in September 2026 and may be undertaken full-time or part-time.

The successful candidate will work on the design, development, and analysis of cryptographic protocols, with a particular focus on privacy and end-to-end verifiability. The project forms part of a broader research programme exploring how cryptographic systems can be designed to be both secure and understandable.

Eligibility Criteria

We seek applicants with a strong background in mathematics and/or computer science. Familiarity with cryptography, number theory, probability theory, or computational algebra would be advantageous.

This 3.5-year studentship is open to UK Home fee-status students only. The award covers Home-rate tuition fees and provides a tax-free stipend at the UKRI rate, which increases annually in line with UKRI guidance. For the 2026/27 academic year, the stipend will be £23,805, including £2,000 London Weighting.

How to Apply

Interested candidates should send:

• a CV
• a motivation letter

to Dr Elizabeth Quaglia at [email protected] by 17 April 2026.

Additional Information

This studentship is part of Dr Elizabeth Quaglia’s EPSRC-funded Open Plus Fellowship on Understandable Cryptography. The fellowship also funds postdoctoral researchers, meaning the successful candidate will join an active research team and a broader programme dedicated to advancing impactful cryptographic research.

Closing date for applications:

Contact: Elizabeth Quaglia, [email protected]

The zero-knowledge group, a subgroup of the cryptography group, at the Institute of Computer Science of the University of Tartu, seeks up to 3 Ph.D. students and one postdoc (up to three persons in total) on the topic of contemporary zero-knowledge proofs and zk-SNARKs. The existing zero-knowledge group comprises of Helger Lipmaa, Matteo Campanelli (part-time position), Janno Siim, Roberto Parisella, and Ph.D students.

Our current research interests include the provable security of zk-SNARKs (including stronger security notions and more realistic cryptographic assumptions), the design of pairing-based, code-based, and lattice-based zk-SNARKs and related primitives (polynomial commitment schemes, folding schemes, etc), and the design of zk-SNARKs for applications such as zkVM and zkML. We collaborate actively with local groups on coding theory and machine learning to further our aims. While primarily focused on academic publishing in top conferences, we are interested in collaborating with ZK companies and staying abreast of developments in practice.

The Ph.D. student must have an MSc or equivalent by this spring, a strong background in mathematics and/or theoretical computer science, and prior background in cryptography. For postdoc candidates, we especially welcome those with a background in the theoretical aspects of proof systems, zk-SNARKs (pairing-based, hash-based, or lattice-based), or applications such as zkML. We expect the postdoc candidate to have published a few papers at IACR conferences or venues of equivalent renown. However, we welcome all exceptional candidates. Some positions will be filled only when we receive strong candidates. Our salaries are competitive with living costs: they are higher than in Southern Europe in absolute terms, while our costs are significantly lower than in Northern Europe. A postdoc/Ph.D. student will receive around 2,600/1,900 euros (depending on qualifications) per month after taxes. See https://crypto.cs.ut.ee/Main/ZKPositions2026 for information on our group and department, and for an application link. (Email applications not possible.)

Closing date for applications:

Contact: Helger Lipmaa ([email protected])

More information: https://crypto.cs.ut.ee/Main/ZKPositions2026

The Symmetric Key and Lightweight Cryptography Lab (SyLLab) at NTU Singapore is looking for candidates for a Research Fellow/Post-Doc position (from fresh Post-Doc to Senior Research Fellow, flexible contract duration) on leakage-resilient modes for symmetric-key cryptography.

Postdoc candidates are expected to have a proven record of publications in top cryptography/security venues, with good experience in provable security.

The position will be funded by a 3-year national research grant. Salaries are competitive and are determined according to the successful applicant's accomplishments, experience and qualifications. We offer an excellent research environment with a highly international team, with flexible working conditions, budget for conferences/equipment, etc.

Interested applicants should send their detailed CVs and references to Prof. Thomas Peyrin ([email protected]). The review of applications starts immediately and will continue until positions are filled.

Closing date for applications:

Contact: [email protected]

We are looking for an associate professor or tenure-track assistant professor to extend and/or strengthen current research and teaching at the Cybersecurity Engineering Section at DTU Compute, Technical University of Denmark. You could be our new colleague if you are a talented and ambitious researcher with a strong passion for cybersecurity and a genuine drive to create societal impact through collaboration with partners across both the private and public sectors. You are expected to embrace and actively contribute to our mission which is to strengthen, advance and integrate foundational and applied research in cybersecurity and cryptography in order to anticipate and respond to evolving scientific, technological, and societal challenges. We are committed to academic excellence within a highly international environment defined by collegial respect, intellectual curiosity, and academic freedom grounded in responsibility. We value intellectual independence and offer you the autonomy to pursue research topics that truly interest you. We recognize and promote diverse forms of talent, supporting your individual interests and strengths. At the same time, we appreciate the importance of balance: for example, we ensure a reasonable teaching load, enabling you to dedicate significant time and energy to advancing your research. The university is located in the greater Copenhagen area, which is acknowledged for its excellent standards of living, childcare and welfare system. The list of special focus areas includes "Cryptogaphy, incuding post-quantum cryptography" among a broad list of cybersecurity sub-areas. The application deadline is 04/30/2026, 11:59 PM Copenhagen Time. For more information, see https://efzu.fa.em2.oraclecloud.com/hcmUI/CandidateExperience/en/sites/CX_2001/job/6948

Closing date for applications:

Contact: Nicola Dragoni ([email protected])

More information: https://efzu.fa.em2.oraclecloud.com/hcmUI/CandidateExperience/en/sites/CX_2001/job/6948

The Theory of Computer Science Group from the Informatics Institute of the University of Amsterdam is seeking a PhD student to carry out cutting-edge research in cryptography, with an expected focus on Secure Multi-Party Computation. For more information and to apply, please visit https://werkenbij.uva.nl/en/vacancies/phd-position-in-secure-multi-party-computation-netherlands-14874. The closing date for the applications is 1 May 2026 (for full consideration, you are encouraged to apply on or before 30 March 2026).

Closing date for applications:

Contact: Divya Ravi ([email protected])

More information: https://werkenbij.uva.nl/en/vacancies/phd-position-in-secure-multi-party-computation-netherlands-14874

The Cryptography Group at the Institute of Computer Science at the University of Tartu invites applications for a PhD position in lattice-based cryptography.

The successful candidate will work on the mathematics of lattices, with a particular focus on their applications in lattice-based cryptography, including discrete Gaussian sampling, digital signature schemes, and cryptographic reductions. Our group includes researchers with expertise in post-quantum cryptography, zk-SNARKs, and coding theory, fostering a collaborative and research-driven environment.

This position offers the chance to work on topics that are both theoretically interesting and practically relevant in modern cryptography. Details about the position and the ideal candidate profile can be found on the application website (link in the headline).

For any inquiries or to apply for the position, submit a letter of motivation, a CV, and the names of two references to Maiara Bollauf (maiara.bollauf at ut.ee).

The PhD position starts on September 1, 2026, and lasts four years. The candidate may later seek further employment, but this is not guaranteed in advance.

Closing date for applications:

Contact: Maiara Bollauf (maiara.bollauf at ut.ee)

More information: https://sites.google.com/view/maiarabollauf/research/phd-in-lattice-based-cryptography

Event date: 10 November to 13 November 2026
Submission deadline: 19 May 2026

This is a full-time on-site role at the Hardware Security and Cryptography Research Lab, University of Idaho, USA, for two fully funded PhD positions in Hardware Security and Cryptography. The role will involve conducting research, working on hardware security projects, developing cryptographic solutions, collaborating with faculty and peers, and contributing to academic publications. Qualifications Strong background in Computer Science, Electrical Engineering, or related field Knowledge of hardware security principles and techniques Experience with cryptographic algorithms and protocols Programming skills in languages such as Verilog, SystemVerilog, Rust, C/C++, Python, TCL scripting VLSI design, EDA tools, such as Cadence Genus and Innovus Prior research experience in hardware security or post-quantum cryptography (PQC) LLM, ML, and their applications in IC and CAD design/automation This funded position offers access to advanced EDA tools, collaborative industry opportunities, and support for publishing in top-tier venues. To apply, please send your CV and academic transcripts to [email protected]. Feel free to reach out with any questions, visit my lab's website (hsc-research.org), or share this opportunity!

Closing date for applications:

Contact: Prof. Zain Ul Abideen [email protected]

More information: https://hsc-research.org/

Signal is a secure messaging app offering end-to-end security for pairwise and group communications. It has tens of millions of users, and has heavily influenced the design of other secure messaging apps (including WhatsApp). Signal has been heavily analysed and, as a result, is rightly regarded as setting the "gold standard" for messaging apps by the scientific community. We present two practical attacks that break the integrity properties of Signal in its advertised threat model. Each attack arises from different features of Signal that are poorly documented and have eluded formal security analyses. The first attack, affecting Android and Desktop, arises from Signal's introduction of identities based on usernames (instead of phone numbers) in early 2022. We show that the protocol for resolving identities based on usernames and on phone numbers introduced a vulnerability that allows a malicious server to inject arbitrary messages into one-to-one conversations under specific circumstances. The injection causes a user-visible alert about a change of safety numbers, but if the users compare their safety numbers, they will be correct. The second attack is even more severe. It arises from Signal's Sealed Sender (SSS) feature, designed to allow sender identities to be hidden. We show that a combination of two errors in the SSS implementation in Android allows a malicious server to inject arbitrary messages into both one-to-one and group conversations. The errors relate to missing key checks and the loss of context when cryptographic processing is distributed across multiple software components. The attack is undetectable by users and can be mounted at any time, without any preconditions. As far as we can tell, the vulnerability has been present since the introduction of SSS in 2018. We disclosed both attacks to Signal. The vulnerabilities were promptly acknowledged and patched: the first vulnerability was fixed two days after disclosure, while the second one was patched after eight days. Beyond presenting these devastating attacks on Signal's end-to-end security guarantees, we discuss more broadly what can be learned about the challenges of deploying new security features in complex software projects.

Decentralized lending protocols rely on liquidation mechanisms tied to volatile oracle-derived prices, creating cascading systemic risk during market downturns. We introduce debt-aware discrete bonding curves (DABC)—piecewise-linear bonding curves with a distinguished floor segment whose price is provably non-decreasing. A reserve invariant couples the curve’s collateral to outstanding debt, enabling a credit facility for issuance-native collateral in which borrowing capacity is anchored to the endogenous floor price rather than a market oracle. We prove that no loan originated at or below the floor-anchored LTV can become under-collateralized due to collateral price declines—eliminating protocol-triggered liquidation for this borrowing model. The trade-off: non-repayment results in permanent token lock, not forced sale. By internalizing issuance, trading, and borrowing in a single contract, the mechanism captures fee revenue that would otherwise accrue to external parties, directing it toward floor elevation. A recursive buy-lock-borrow-buy loop enables leveraged positions without liquidation risk; token launches are the most compelling application. To the best of our knowledge, this work provides the first fully formalized treatment in which borrowing safety is derived from a debt-aware reserve invariant and a provably non-decreasing endogenous floor price. We verify the mechanism through stateful fuzz testing and formal verification of a concrete Solidity implementation.

In this work, we present new cryptanalytic attacks on recently proposed, theory-inspired constructions of weak pseudorandom functions (weak-PRFs). We demonstrate attacks on several such designs, showing that the initial security arguments require significant refinement. Methodologically, our approach relies on novel observations about the structure of cyclic matrices, applications of Wagner's generalized birthday technique, and conversion into polynomial systems over $\mathbb{F}_3$. These findings highlight the need for a more careful analysis of those weak-PRF candidates

We present Remise, a two-server authorized anonymous communication system built on Distributed Oblivious RAM (DORAM). Remise supports two modes of opera- tion: (i) an anonymous bulletin board, where messages are publicly revealed at the end of each epoch without linking senders to messages, and (ii) anonymous commu- nication channels, where messages remain secret-shared, and writers selectively grant and revoke read access to chosen readers. In both modes, the two servers execute read and write operations without learning which indices are accessed, which authorization tokens are used, or which relationships exist between writers and readers, assuming at least one honest server. A central contri- bution of Remise is a lightweight and efficient access- control mechanism. Authorization proofs are maintained in secret-shared form across the two servers, enabling oblivious verification while preventing leakage even un- der client–server collusion. Unlike prior DPF-based sys- tems, Remise provides built-in auditing by having the semi-honest servers generate standard-basis vector shares internally, eliminating the need for server-side DPF va- lidity checks. We implement a prototype of Remise and evaluate it under realistic network conditions. Our ex- periments show 80×improvement in online server time when compared to PACL (Spectrum) (IEEE S&P 2023) for databases of size $22^{24}$

We present CHOPIN, a pairing-based multilinear polynomial commitment scheme (PCS) achieving constant proof size and a linear-time prover, constructed modularly from a bivariate PCS. CHOPIN generalizes the recent compilers from univariate to multilinear PCS MERCURY (Eagen and Gabizon, ePrint 2025/385) and Samaritan (Ganesh, Patranabis, and Singh, ASIACRYPT 2025). Due to its modular design, we obtain a direct proof of knowledge soundness via a reduction to the knowledge soundness of the underlying bivariate PCS in the standard model. In particular, our analysis avoids idealized models such as the Algebraic Group Model.

When instantiated with the bivariate KZG scheme (Papamanthou, Shi, and Tamassia, TCC 2013), CHOPIN achieves a similar proof size to Mercury and Samaritan while offering a two-fold speedup in the main bottleneck for the prover time, which arises because CHOPIN requires only a single large MSM proportional to the size of the committed multilinear polynomial, in contrast to the two large MSMs required by the prior works, at the cost of one additional pairing for the verifier.