As zero-knowledge proof systems become increasingly prevalent, there is a need for arithmetic hash functions that operate efficiently over finite fields. Unlike hash functions that use bitwise operations, such as SHA-256, arithmetic hash functions use native field operations. When expressed as circuits over finite fields of large prime order, these arithmetic designs result in comparatively lower circuit complexity. Two prevalent examples of arithmetic hash functions are Poseidon and Rescue-Prime. In this work, we create Halo2 circuits for the Poseidon and Rescue-Prime permutations, derived from a shared circuit construction. We benchmark the resulting circuits and report low-level circuit metrics. Our comparative analysis highlights both the differences between the permutations and their tradeoffs in the context of Halo2 circuits. The shared circuit construction is also contributed as a controlled methodology for benchmarking permutations in Halo2 circuits. This work corresponds to the v1.0.1 release of the accompanying open-source implementation.
In the traditional narrative, secp256k1 is the "Math" and MPC is the "Security Layer." We show that the Curve (sp256) uses the Weierstrass form to create a "Symmetric Loop." The Protocol (MPC) uses "Shards" to create a "Distributed Loop." Both rely on the user believing that the Public key and the Private key are disconnected. In reality, MPC is just sp256k1 expanded into a room of people. By analyzing the mpc-cmp repository and the I2OSP standard, we show that the "Secret" is not an emergent property of complex computation but a Symmetric Mechanical Alignment front-loaded into the first octet M0 as an Identity Pulse 10 (0x0a). We prove that the Paillier Encryption and Zero-Knowledge Range Proofs utilized in industrial protocols (e.g., Taurus, Fireblocks) do not change the deterministic hardware alignment which explains why the path from a Public Address to a Private Key is a straight, symmetric line.
Zhuo Wu, Shi Qi, Xinxuan Zhang, Yi Deng · 6 authors
Abstract Recent years have seen the widespread adoption of zkSNARKs constructed over small fields, including but not limited to, the Goldilocks field, small Mersenne prime fields, and tower of binary fields. Their appeal stems primarily from their efficacy in proving computations with small bit widths, which facilitates efficient proving of general computations and offers significant advantages, notably yielding remarkably fast proving efficiency for tasks such as proof of knowledge of hash preimages. Nevertheless, employing these SNARKs to prove algebraic statements (e.g., RSA, ECDSA signature verification) presents efficiency challenges, particularly in critical applications like zk-bridges and zkVMs that require verifying standard cryptographic primitives. To address this problem, we first define a new circuit model: arithmetic circuits with additional exponentiation gates . These gates serve as fundamental building blocks for establishing more intricate algebraic relations. Then we present a Hash-committed Commit-and-Prove (HCP) framework to construct Non-interactive Zero-knowledge (NIZK) proofs for the satisfiability of these circuits. Specifically, when proving knowledge of group exponentiations in discrete logarithm hard groups and RSA groups, compared to verifying complex group exponentiations within SNARK circuits, our approach requires proving only more lightweight computations within the SNARK, such as zk-friendly hash functions (e.g., Poseidon hash function). The number of these lightweight computations depends solely on the security parameter. This differentiation leads to substantial speedups for the prover relative to direct SNARK methods, while maintaining competitive proof size and verification cost.
Zhichao Wang, Xudong Zhu, Xinxuan Zhang, Yi Deng · 5 authors
Abstract Time-release cryptography is a flourishing research area with a long history and has been extensively studied. In this work, we enrich it by introducing a novel concept: a time-release zero-knowledge proof (TRZKP). A TRZKP is a non-interactive zero-knowledge proof that allows one to publish a proof for a given relation $$R_\mathcal {L}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>R</mml:mi> <mml:mi>L</mml:mi> </mml:msub> </mml:math> , such that anyone can only finish the verification after time $$\textbf{T}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>T</mml:mi> </mml:math> by performing a sequential computation. This work formalizes the concept of TRZKP and presents light constructions for the time-release version of any NIZK obtained from a public-coin protocol via Fiat-Shamir transformation. TRZKPs can be applied to provide time-release authentication, for example, they can be employed to construct verifiable timed signatures (VTS), introduced by Thyagarajan et al. (CCSâ20). Through both theoretical and practical analysis, our construction has advantages over existing VTS for Fiat-Shamir signatures. Specifically, when instantiated with Shnorr signature, our VTS signing time remains basically unchanged as the delay time grows, and is preferable for longer delay times; our VTS verification time is significantly small (on the level of milliseconds, while existing works on the level of seconds), and our VTS size is 67 times smaller than the state-of-the-art. It also has the time-verifiability property, which ensures the signature is recoverable after the specified time.
The modern integrated circuit ecosystem is increasingly reliant on third-party intellectual property integration, which introduces security risks, including hardware Trojans and security vulnerabilities. Addressing the resulting trust deadlock between IP vendors and system integrators without exposing proprietary designs requires novel privacy-preserving verification techniques. However, existing privacy-preserving hardware verification methods are all simulation-based and fail to offer formal guarantees. In this paper, we propose ZK-CEC, the first privacy-preserving framework for hardware formal verification. By combining formal verification and zero-knowledge proof (ZKP), ZK-CEC establishes a foundation for formally verifying IP correctness and security without compromising the confidentiality of the designs. We observe that existing zero-knowledge protocols for formal verification are designed to prove statements of public formulas. However, in a privacy-preserving verification context where the formula is secret, these protocols cannot prevent a malicious prover from forging the formula, thereby compromising the soundness of the verification. To address these gaps, we first propose a blueprint for proving the unsatisfiability of a secret design against a public constraint, which is widely applicable to proving properties in software, hardware, and cyber-physical systems. Based on the proposed blueprint, we construct ZK-CEC, which enables a prover to convince the verifier that a secret IP's functionality aligns perfectly with the public specification in zero knowledge, revealing only the length and width of the proof. We implement ZK-CEC and evaluate its performance across various circuits, including arithmetic units and cryptographic components. Experimental results show that ZK-CEC successfully verifies practical designs, such as the AES S-Box, within practical time limits.
Open access
4 source records
cs.CR
cs.LO
Physical Unclonable Functions (PUFs) and Hardware Security
Chimeremma Sandra Amadi, Simeon Okechukwu Ajakwe, Taesoo Jun
Secure and auditable data sharing in large-scale Internet of Things (IoT) environments remains a significant challenge due to weak trust coordination, limited scalability, and susceptibility to emerging quantum attacks. This study introduces a hybrid blockchain-based framework that integrates post-quantum cryptography with intelligent anomaly detection to ensure end-to-end data integrity and resilience. The proposed system utilizes Hyperledger Fabric for permissioned device lifecycle management and Ethereum for public auditability of encrypted telemetry, thereby providing both private control and transparent verification. Device identities are established using quantum-entropy-seeded credentials and safeguarded with lattice-based encryption to withstand quantum adversaries. A convolutional long short-term memory (CNNâLSTM) model continuously monitors device behavior, facilitating real-time trust scoring and autonomous revocation via smart contract triggers. Experimental results demonstrate 97.4% anomaly detection accuracy and a 0.968 F1-score, supporting up to 1000 transactions per second with cross-chain latency below 6 s. These findings indicate that the proposed architecture delivers scalable, quantum-resilient, and computationally efficient data sharing suitable for mission-critical IoT deployments.
In recent years, the number-theoretic transform (NTT) has become increasingly common in cryptography, in part due to multiple lattice-based cryptographic schemes being selected for standardization during the NIST PQC competition. Indeed, polynomial multiplications are one of the most computing intensive operations in these schemes and the NTT is crucial in decreasing the performance cost. The NTT also appears in other areas such as fully homomorphic encryption (FHE) and zero-knowledge proofs (ZKP) which are increasingly used in privacy-preserving applications. In this paper, we show how to formally specify the NTT in the Rocq proof assistant, and how we used this specification to automatically derive formally verified implementations of both complete and incomplete NTTs for multiple cryptographic schemes.
The ongoing transition to post-quantum cryptography has highlighted the need for digital signature schemes offering diverse performance and security trade-offs. Among the candidates in NISTâs ongoing post-quantum signature standardisation process is FAEST, a scheme built upon the Vector Oblivious Linear Evaluation in-the-Head (VOLEitH) paradigm introduced in 2023. VOLEitH enables efficient zero-knowledge proofs with competitive signature sizes under conservative assumptions, allowing FAEST to rely primarily on the one-wayness of the Advanced Encryption Standard (AES). Despite their promising efficiency, VOLEitH-based signature schemes have remained relatively unexplored from a physical security perspective. In this paper, we present the first side-channel security evaluation. Specifically, we demonstrate two single-trace, deep learning-assisted power analysis attacks on the masked implementation of FAEST by Aranha, Degn, Eilath, Nielsen, and Scholl. These attacks exploit leakage from witness bits and VOLE tag computations, recovering the full secret key with success probability above 0.99 from a single signature on an ARM Cortex-M4 processor. We further analyse how the VOLEitH construction enables profiling of VOLE tags without knowledge of the secret key and how even partial leakage of these tags compromises security. Finally, we discuss practical countermeasures to mitigate such leakages and strengthen the physical resilience of VOLEitH-based signature implementations.
Address verification and spend limit checks in card and instant payment systems expose cardholder ZIP codes and velocity histories to gateways and intermediaries, which increases the privacy impact of breaches. At the same time, issuers rely on these checks to control fraud within strict two to three hundred millisecond authorization budgets. This paper presents ZK-AVS, a design that replaces plaintext AVS and spend limit evaluation with zero knowledge proofs produced on the customer device and verified at the payment gateway. The issuer stores commitments to the cardholder ZIP and per window spend counters, and the device proves that its ZIP matches the committed value and that the proposed transaction keeps cumulative spend within the configured limit, without revealing the underlying values. We instantiate a synthetic workload of fifty thousand transactions and show that AVS mismatch and limit pressure carry useful fraud signal that can be exposed as proof outcomes. The design is structured to fit within sub three hundred millisecond budgets on commodity devices, while removing direct exposure of address and spend history data at the gateway and keeping changes largely at endpoints.
This paper presents the post-quantum integrity architecture designed and being implemented within Smart Astro among the rst known platforms delivering Deterministic Engine Computed, AI-Narrated, Blockchain-Veried life guidance at scale. Smart Astro operates across 18 active life-decision intents and over 40 auspicious-timing categories, serving users globally through a real-time, pay-per-question model. Classical asymmetric cryptography underpinning current blockchain infrastructure is vulnerable to Shor's algorithm on fault-tolerant quantum computers. Smart Astro addresses this proactively by integrating NIST-standardised post-quantum cryptographic primitives FIPS 203 (ML-KEM), FIPS 204 (ML-DSA), and FIPS 205 (SLH-DSA) alongside a Solana-anchored proof chain already live in production. The central architectural contribution is a layered separation of concerns: the deterministic engine computes a structured, repeatable output; cryptographic proof generation runs asynchronously outside the delivery path; the AI narration layer is isolated from the proof chain; and only a commitment hash is written to the Solana ledger, with the full postquantum signature bundle stored o-chain. Every paid answer carries an independently veriable SA-PROOF identier with zero personally identiable information (PII) on-chain. A hybrid ML-DSA + SLH-DSA signature scheme provides defence in depth against both lattice cryptanalysis and harvest-now-decrypt-later adversaries. This architecture establishes a replicable standard for cryptographic integrity in AI-narrated deterministic knowledge systems.
Open access
Cryptography and Data Security
Cryptographic Implementations and Security
Physical Unclonable Functions (PUFs) and Hardware Security
Quasi-adaptive non-interactive zero-knowledge (QA-NIZK) arguments are fundamental cryptographic primitives widely used in privacy-preserving technologies such as anonymous credentials, group signatures, e-cash, and blockchain-based applications. We present the first tightly secure unbounded simulation sound quasi-adaptive non-interactive zero-knowledge argument system from simple assumptions. The construction has a security loss ofO(1), a compact common reference string, constant size proofs, and its security relies on the hardness of the well-known SXDH assumption. Our result improves state-of-the-art (Couteau and Hartmann, CRYPTO 2020) in terms of the proof size (about three times), a lower security loss, and also with respect to the underlying hardness assumptions. The tight security reduction enables shorter key-length recommendations, leading to improved concrete efficiency. Our main technical contribution is a novel proof technique inspired by the randomization technique of the Naor-Yung double-encryption paradigm and the adaptive partitioning due to Hofheinz (EUROCRYPT 2017).
Consumer Healthcare Devices (CHD) in Healthcare 4.0 (HC 4.0) increasingly generate continuous physiological data that are transformed into 3-dimensional holographic visualizations for remote monitoring, diagnosis, and clinical decision support. However, existing IoMT and blockchain (BC)-based healthcare systems protect data storage and access but do not verify the integrity, freshness, or provenance of holographic patient representations, leaving such visualizations vulnerable to spoofing, replay, and slice-level tampering. This paper proposes a Blockchain-Assisted Holographic Counterpart (BAHC) framework that cryptographically binds wearable devices to holographic updates using PUF-derived Holographic Authentication Tokens (HAT), enforces slice-level integrity through a Merkle-Hologram-Commitment Tree (Merkle-HC Tree), and anchors updates on a permissioned Proof-of-Authority (PoA) BC. Privacy-preserving access control and verification are achieved using Ciphertext-Policy Attribute-Based Encryption (CP-ABE) and Zero-Knowledge Proofs (ZKPs). The framework is evaluated on a controlled experimental testbed emulating 500 concurrent patient streams using independent public physiological datasets and public MRI volumes for synthetic hologram generation, measuring end-to-end latency, anomaly detection performance, rendering efficiency, and blockchain throughput under up to 100 validators. Experimental results show a 68.6% reduction in holographic rendering latency, a 34% reduction in diagnostic latency, a relative 27% improvement in anomaly detection performance, and sustained throughput close to 500 transactions per second, demonstrating that BAHC provides a scalable and trustworthy foundation for secure holographic monitoring in HC 4.0 systems.
Chaos-based Image/Signal Encryption
Physical Unclonable Functions (PUFs) and Hardware Security
Michael Adjedj, Constantin Blokh, Geoffroy Couteau, Arik Galansky · 6 authors
We present a novel protocol for two-party ECDSA that achieves two rounds (a single back-and-forth communication) at the cost of a single oblivious linear function evaluation (OLE). In comparison, the previous work of Boneh, Haitner, Lindell, and Segev (EUROCRYPT 2025) achieves two rounds but requires expensive zero-knowledge proofs on top of the OLE. We demonstrate this by proving that in the generic group model, any adversary capable of generating forgeries for our protocol can be transformed into an adversary that finds preimages for the ECDSA message digest function (e.g., the SHA family). Interestingly, our analysis is closely related to, and has ramifications for, the âpresignaturesâ mode of operationâCanetti, Gennaro, Goldfeder, Makriyannis, and Peled (CCS 2020), Groth and Shoup (EUROCRYPT 2022).Motivated by applications to embedded cryptocurrency wallets, where a single server maintains distinct, shared public keys with separate clients (i.e., a star-shaped topology), and with the goal of minimizing communication, we instantiate our protocol using Paillier encryption and suitable zero-knowledge proofs. To reduce computational overhead, we thoroughly optimize all components of our protocol under sound cryptographic assumptions, specifically small-exponent variants of RSA-style assumptions.Finally, we implement our protocol and provide benchmarks. At the 128-bit security level, the signing phase requires approximately 50 ms of computation time on a standard linux machine, and 2 KB of bandwidth.
Rajasekaran P., Duraipandian M., Johny Renoald Albert, R. Jamuna · 5 authors
The Internet of Medical Things (IoMT) in the IoT with Cloud Healthcare (CHI) creates a high volume of realâtime medical data, but traditional compression methods suffer high computation costs, privacy leaks and quantum attacks, while advanced cryptographic algorithms such as homomorphic encryption are costly and have poor scalability for the realâtime system application. In this work, we propose a quantumâenhanced zeroâknowledge healthcare compression network (QZâHCN) that associates zeroâknowledge proofs (ZKPs) with quantumâinspired deep learning (QIDL) by introducing an innovative adaptive quantumâsupported ZKP verification mechanism (AQâZKV) and a quantum fusion autoconventional neural network (QFâAutoCNN) technique to achieve efficient, privacyâpreserving compression. For healthcare IoT datasets, QZâHCN can reach 98.16% in accuracy, 97.09% in Fâmeasure, 96.32% in precision and 97.45% in recall, with a throughput of 449.57 bits/s; processing time is reduced to 0.85 s, and memory cost is minimised to be only 192 kbits, which outperforms CNNâEncryption (90.23% accuracy), proxy reâencryption and homomorphic encryption by at most 13 percentage points in accuracy and 75 percentage points in memory efficiency. The secure and scalable management for CHI data is achieved by QZâHCN, which solves the problems of privacy threats and space costs of realâtime medical applications.
Shraddha M. Naik, Huned Materwala, Davor SvetinoviÄ
Maximal Extractable Value (MEV) poses significant threats to the security and fairness of Ethereum's decentralized finance ecosystem by enabling participants to exploit transaction ordering to extract profits at the expense of others. Heuristic-based detection methods have been widely adopted to identify MEV transactions such as sandwich, arbitrage, and liquidation. However, a lack of standardized evaluation across heuristics limits the ability to compare their detection behavior and computational characteristics. This paper presents a unified experimental framework to systematically evaluate the detection capabilities, agreement rates, and resource efficiency of existing heuristic approaches. An agreement metric is introduced to quantify consistency across detection methods. Additionally, we assessed resource utilization and execution time to evaluate computational scalability. Our empirical findings reveal that while these approaches exhibit scalability, their reliability, measured in terms of detection consistency, varies significantly across different MEV types. Agreement rates averaged 0.53 for sandwich detection, 0.40 for arbitrage, and 0.81 for liquidation, highlighting substantial differences in detection capabilities and heuristic formulations. These findings offer valuable insights into the practical challenges of achieving consistent MEV detection and highlight the need for developing more robust security countermeasures.