Blockchain Papers

Mazharul Hasan, Mohammad Jabed Morshed Chowdhury, Kamanashis Biswas, Mahmudul Hasan · 5 authors

Non-Fungible Tokens (NFTs) have revolutionized the blockchain ecosystem by enabling the decentralized representation and ownership of unique digital assets. However, the NFT landscape is increasingly susceptible to security vulnerabilities and attack vectors, necessitating robust protection mechanisms. This research presents a comprehensive analysis and a structured framework to enhance the security of NFT transactions. The relevant studies were identified using a snowballing method as the paper searching approach, ensuring systematic and comprehensive coverage of the existing literature. Specifically, it examines critical security risks, including ownership duplication, duplicate token generation, unauthorized asset withdrawal, asset replication, and metadata manipulation. A key contribution of this study is the development of a detailed taxonomy of NFT-related threats and attacks, providing researchers and practitioners with a consolidated perspective on the evolving security landscape. Furthermore, we introduce and analyze attack vectors, demonstrating its implications and proposing an effective mitigation strategy.

Joel Poncha Lemayian, Ghyslain Gagnon, Kaiwen Zhang, Pascal Giard

ABSTRACT Cryptocurrency blockchain networks safeguard digital assets using cryptographic keys, with wallets playing a critical role in generating, storing, and managing these keys. Wallets, typically categorized as hot and cold, offer varying degrees of security and convenience. However, they are generally software‐based applications running on microcontrollers. Consequently, they are vulnerable to malware and side‐channel attacks, allowing perpetrators to extract private keys by targeting critical algorithms, such as ECC, which processes private keys to generate public keys and authorize transactions. To address these issues, this work presents EthVault, the first hardware architecture for an Ethereum hierarchically deterministic cold wallet, featuring hardware implementations of key algorithms for secure key generation. Also, an ECC architecture resilient to side‐channel and timing attacks is proposed. Moreover, an architecture of the child key derivation function, a fundamental component of cryptocurrency wallets, is proposed. The design minimizes resource usage, meeting market demand for small, portable cryptocurrency wallets. FPGA implementation results validate the feasibility of the proposed approach. The ECC architecture exhibits uniform execution behavior across varying inputs, while the complete design utilizes only 27%, 7%, and 6% of LUTs, registers, and RAM blocks, respectively, on a Xilinx Zynq UltraScale+ FPGA.

Lin Fei, T Zhang, Ziyang Gong, Fei–Yue Wang

In recent years, generative artificial intelligence (GenAI) has demonstrated remarkable capabilities in high-stakes domains such as molecular science. However, challenges related to the verifiability and structural privacy of its outputs remain largely unresolved. This paper focuses on the task of molecular toxicity repair. It proposes a structure-private verification framework—ToxiEval-ZKP—which, for the first time, introduces zero-knowledge proof (ZKP) mechanisms into the evaluation process of this task. The system enables model developers to demonstrate to external verifiers that the generated molecules meet multidimensional toxicity repair criteria, without revealing the molecular structures themselves. To this end, we design a general-purpose circuit compatible with both classification and regression tasks, incorporating evaluation logic, Poseidon-based commitment hashing, and a nullifier-based replay prevention mechanism to build a complete end-to-end ZK verification system. Experimental results demonstrate that ToxiEval-ZKP facilitates adequate validation under complete structural invisibility, offering strong circuit efficiency, security, and adaptability, thereby opening up a novel paradigm for trustworthy evaluation in generative scientific tasks. The code is available at: https://github.com/DeepYoke/ToxiEval-ZKP .

Aleksandra Szczegielniak-Rekiel, Krzysztof Kanciak, Jan M. Kelner

This study explored the diverse applications of zero-knowledge proofs (ZKPs) in next-generation network technologies, particularly in fifth-generation (5G) and emerging sixth-generation (6G) systems. ZKPs are cryptographic methods that enable one party to prove the validity of a statement without revealing the statement itself, thereby offering significant advantages in privacy-preserving authentication and authorization. Given these properties, ZKPs have garnered increasing research attention in contexts such as the Internet of Things (IoT), vehicular communications, and telecommunication protocols. To the best of our knowledge, this is the first study to provide a comprehensive, taxonomy-driven analysis of ZKP applications specifically designed for 5G and beyond. We categorize existing solutions according to the type of application, the underlying cryptographic technology, maturity level, and relevance to 6G. Furthermore, this paper examines how ZKPs can help mitigate various cybersecurity threats, such as distributed denial-of-service (DDoS) attacks, man-in-the-middle attacks, and location tracking. We also assess recent advancements in ZKP acceleration techniques and highlight the key implementation challenges. Finally, this study outlines promising directions for future research in this rapidly evolving field.

Usman Khalil, Mueen Uddin, Hashem Alaidaros, Adnan Akhunzada

Abstract In the rapidly evolving landscape of IoT-enabled smart devices, significant challenges persist in integration to web3, security, and data reliability. This research presents the design and integration of IoT assets, particularly devices, through the Novel Decentralized Smart City of Things (DSCoT) framework. ESP32 microcontrollers serve as Ethereum clients, generating Externally Owned Accounts (EOA) for device identification and authentication. Despite resource constraints, including limited computational capabilities, essential libraries that manage tasks such as Wi-Fi module control, interaction with Ethereum-based blockchains, TCP connection management, and EEPROM operations for persistent data storage. The code is structured with functions for Wi-Fi setup, TCP API requests, and secure communication challenges. Integration involves compiling and flashing the code onto ESP32 devices, verifying EOA generation, and mapping devices, fog nodes, and users through smart contract interactions. The deployment process culminates in the generation of Non-Fungible Tokens (NFTs) for user authentication, with transaction verification on the Goerli testnet confirming successful DSCoT edge system implementation. This research underscores the importance of secure and decentralized integration of IoT-enabled smart devices to the blockchain, enhancing performance while ensuring security and transparency.

Shashank Balla, Yiming Zhao, Farinaz Koushanfar

Protecting integrated circuits (ICs) from piracy and theft throughout their lifecycle is a persistent and complex challenge. In order to safeguard against illicit piracy attacks, this work proposes a novel framework utilizing Non-Fungible Tokens (NFTs) called ICtokens, uniquely linked to their corresponding physical ICs. Each ICtoken contains comprehensive information, including authentication data, supply chain stage and status, ownership details, and other IC metadata, while also making provision for the secure integration of a logic-locking key. Designed to be publicly logged, ICtokens securely obscure metering information without compromising functionality. In addition, the ICtracker, a distributed ledger technology powered by a swift and energy-efficient consortium blockchain, is used to register and manage ICtokens and their respective owners, tracking all associated interactions. This robust ledger guarantees the traceability and auditing of ICtokens while simultaneously developing a product-level NFT at every transaction point within the supply chain. Consequently, a scalable framework is established, creating unique, immutable digital twins for ICs and IC-embedded products in the form of ICtokens and their transactions. This provides a robust and reliable supply chain trail back to the original IP owner, while also offering unprecedented assurance to consumers of IC-embedded products. The rich information contained within ICtokens facilitates more detailed audits than previous proposals for IC supply chain monitoring. A proof-of-concept, implemented as an open-source solution, ensures the ease of adoption of the proposed framework.

Jing Jiang, Xiaofeng Wang, Qianqian Xing, Jin Tang

Currently, personal information leakage and identity theft have become risks that cannot be ignored. As a robust authentication mechanism, multi-factor authentication (MFA) has gained prominence. However, many existing MFA schemes based on certificate-less public key cryptography amalgamate multiple authentication factors into a single factor for local verification, which fails to achieve independent authentication of each factor and is difficult to resist internal privilege attacks. To address these issues, this paper proposes a certificate-less multi-factor privacy authentication scheme based on elliptic curve cryptography. The proposed scheme divides the full private key into multiple authentication factors and employs the Schnorr zero-knowledge proof technique to independently generate challenge values for each factor, facilitating separate authentication of multiple factors. Notably, this approach eliminates the need to reconstruct the full private key during the authentication process, thereby effectively mitigating the risk of private key leakage.

Ingrid Verbauwhede

Hardware security is the root of trust in all modern ICT (Information and Communications Technology) systems. However, hardware security means something different for different communities. It has also a very wide scope. It covers efficient, secure implementations of new generations of cryptography such as light-weight crypto, post-quantum crypto as well as advanced schemes such as zero-knowledge proofs, fully homomorphic encryption, and computing on encrypted data in general [1][2]. Yet, implementations also must resist a wide variety of side-channel, fault, and micro-architectural attacks. Post-quantum algorithms might resist the attacks developed for quantum computers. Yet, they also have to be resistant to these attacks on classic platforms, see e.g. [3]. Security protocols rely on more than only cryptographic algorithms. They require analog and digital circuit techniques to design quality true random number generators, physically unclonable functions, secure key storage, and many more [4]. A recent report on "Revitalizing the U.S. Semiconductor Ecosystem" (from Executive Office of the President, President's Council of Advisors on Science and Technology, September 2022) [5] describes a set of recommendations on semiconductors and system security. In this presentation, we will demonstrate how our research addresses these recommendations and we will illustrate this with recent results and ongoing projects.

Jiajing Wu, Kaixin Lin, Dan Lin, Bozhao Zhang · 6 authors

Cross-chain bridges are essential decentralized applications (DApps) to facilitate interoperability between different blockchain networks. Unlike regular DApps, the functionality of cross-chain bridges relies on the collaboration of information both on and off the chain, which exposes them to a wider risk of attacks. According to our statistics, attacks on cross-chain bridges have resulted in losses of nearly 4.3 billion since 2021. Therefore, it is particularly necessary to understand and detect attacks on cross-chain bridges. In this paper, we collect the largest number of cross-chain bridge attack incidents to date, including 49 attacks that occurred between June 2021 and September 2024, of which 22 were attacks on cross-chain bridge business logic. Our analysis reveal that attacks against cross-chain business logic cause significantly more damage than those that do not. These cross-chain attacks exhibit different patterns compared to normal transactions in terms of call structure, which effectively indicates potential attack behaviors. Given the significant losses in these cases and the scarcity of related research, this paper aims to detect attacks against cross-chain business logic, and propose the BridgeGuard tool. Specifically, BridgeGuard models cross-chain transactions from a graph perspective, and employs a two-stage detection framework comprising global and local graph mining to identify attack patterns in cross-chain transactions. We conduct multiple experiments on the datasets with 203 attack transactions and 40,000 normal cross-chain transactions. The results show that BridgeGuard's reported recall score is 36.32% higher than that of state-of-the-art tools and can detect unknown attack transactions.

Chinmay

The world has seen enormous disruption by new age technologies in every domain of today's economy including the arena of art, music and entertainment. Furthermore, the impact of artificial intelligence and blockchain technology particularly the Non Fungible Tokens (NFTs) has overwhelmed scholars about their understanding of laws related to intellectual property. Advances in technology are expanding the scope of intellectual property beyond traditional patents, trademarks, designs, trade secrets, plant breeders' rights, and more. Various issues related to intellectual property have taken centre stage in the world of NFTs and Blockchains. Intellectual property disputes over virtual goods and NFTs are on the rise, and countries across the world are endeavoring to address the issues related to the protection of virtual goods. This article analyses the nature and scope of protection granted to virtual goods and NFTs in major jurisdictions viz the US and China. Further, the article analyses if the provisions of Indian IP Laws particularly the Trademarks and Designs Acts are sufficient to grant protection to the virtual goods.

Nezer Zaidenberg, Michael Kiperberg

We present VirtSecIO, a hypervisor-based platform for executing secure modules. VirtSecIO provides the modules with secure paths to peripheral devices, which can be shared between the modules and the operating system. Moreover, VirtSecIO is a thin hypervisor with a negligible performance overhead and a minimal attack surface. We demonstrate VirtSecIO’s abilities by developing HyperWallet, a secure module that acts as a hardware crypto-wallet, without requiring any dedicated hardware.

Jun Kong Phiang, Vivian Yong Siew Yee, Hafizuddin Bin Hilmi, Dedree Leonna Lai · 6 authors

The Industrial Internet of Things (IIoT) has revolutionized industrial processes, offering automation and data-driven decision-making. However, this interconnectedness brings new security challenges, especially in crucial infrastructure sectors. Traditional security measures are inadequate, leading to the exploration of innovative solutions. Blockchain technology has emerged as a promising solution due to its decentralized and immutable nature. This paper proposes a Hybrid Blockchain-Based Authentication Mechanism for IIoT, combining Delegated Proof of Stake (DPoS) and Elliptic Curve Cryptography (ECC). The hybrid architecture utilizes public and private blockchains to ensure scalability, efficiency, and security. Lightweight consensus algorithms, DPoS, are incorporated to optimize performance, while ECC provides efficient cryptographic techniques suitable for IIoT environments. An interoperable framework facilitates seamless integration with existing infrastructure, ensuring regulatory compliance and compatibility. Decentralized identity management further enhances security and privacy. Results and analysis demonstrate the effectiveness of the proposed solution, positioning hybrid blockchain architecture as the most suitable approach for enhancing security in IIoT environments.

Victor Takashi Hayashi, Wilson Vicente Ruggiero

Although hardware trojans impose a relevant threat to the hardware security of RISC-V and Web3 applications, existing datasets have a limited set of examples, as the most famous hardware trojan dataset TrustHub has 106 different trojans. RISC-V specifically has study cases of three and four different hardware trojans, and no research was found regarding Web3 hardware trojans in modules such as a hardware wallet. This research presents a dataset of 290 Verilog examples generated with ChatGPT-4 Large Language Model (LLM) based on 29 golden models and the TrustHub taxonomy. It is expected that this dataset supports future research endeavors regarding defense mechanisms against hardware trojans in RISC-V, hardware wallet, and hardware Proof of Work (PoW) miner.

Daniel Commey, Sena Hounsinou, Garth V. Crosby

This paper presents a framework for securing blockchain-based IoT systems by integrating Physical Unclonable Functions (PUFs) and Zero-Knowledge Proofs (ZKPs) within a Hyperledger Fabric environment. Our approach leverages PUFs for robust device authentication and ZKPs for privacy-preserving transaction processing, addressing key challenges of security, privacy, and scalability in IoT systems. The framework’s architecture utilizes Hyperledger Fabric’s modular design and private channels to enhance scalability. Off-chain experimental results demonstrate the framework’s feasibility, with compact proof sizes (median 805 bytes) and efficient processing times (average 2,800 ms end-to-end). A comprehensive security analysis shows the framework’s resilience against various attacks, including device impersonation and data tampering. This work provides a foundation for secure and scalable blockchain-based IoT systems, with directions for future on-chain implementation and optimization for resource-constrained devices.

Marisol García‐Valls, Alejandro M. Chirivella-Ciruelos

Non-functional requirements related to safety, security, and timeliness have made cyber–physical systems (CPS) initially reluctant to their integration with blockchain technology. Despite the multiple advantages of blockchain like improved data security and traceability, the main reasons that have slowed down its adoption in CPS still remain. Examples of these are the inherent overhead of accessing the distributed ledger and the security incidents that a number of blockchain networks have suffered since its inception. This paper presents VelogCPS, a novel middleware that guarantees that logic and data managed by blockchain networks of cyber–physical systems is verified and generated by a legitimate source. Thus, VelogCPS avoids a kind of security incidents that impact the authenticity and integrity of the logic and data managed in blockchain networks. By authenticity we refer to provenance authenticity of the involved smart contracts, i.e., the perfect matching between the source-code and a corresponding advertised smart-contract logic. This middleware ensures that the entities that participate to a CPS use solely authentic logic. For this, our approach leverages block verification services and enforces them through the operation workflow. As a result, the middleware guarantees that the CPS participants use and share authentic logic. Our approach is validated by providing an implementation on a real blockchain network, employing actual smart contract verifier logic, and analysing the temporal behavior of the overall system operations; this ensures its utility for CPS and IoT.

Jonathan Fior

BACKGROUND: A blockchain can be described as a distributed ledger database where, under a consensus mechanism, data are permanently stored in records, called blocks, linked together with cryptography. Each block contains a cryptographic hash function of the previous block, a timestamp, and transaction data, which are permanently stored in thousands of nodes and never altered. This provides a potential real-world application for generating a permanent, decentralized record of scientific data, taking advantage of blockchain features such as timestamping and immutability. IMPLEMENTATION: Here, we propose INNBC DApp, a Web3 decentralized application providing a simple front-end user interface connected with a smart contract for recording scientific data on a modern, proof-of-stake (POS) blockchain such as BNB Smart Chain. Unlike previously proposed blockchain tools that only store a hash of the data on-chain, here the data are stored fully on-chain within the transaction itself as "transaction input data", with a true decentralized storage solution. In addition to plain text, the DApp can record various types of files, such as documents, images, audio, and video, by using Base64 encoding. In this study, we describe how to use the DApp and perform real-world transactions storing different kinds of data from previously published research articles, describing the advantages and limitations of using such a technology, analyzing the cost in terms of transaction fees, and discussing possible use cases. RESULTS: We have been able to store several different types of data on the BNB Smart Chain: raw text, documents, images, audio, and video. Notably, we stored several complete research articles at a reasonable cost. We found a limit of 95KB for each single file upload. Considering that Base64 encoding increases file size by approximately 33%, this provides us with a theoretical limit of 126KB. We successfully overcome this limitation by splitting larger files into smaller chunks and uploading them as multi-volume archives. Additionally, we propose AES encryption to protect sensitive data. Accordingly, we show that it is possible to include enough data to be useful for storing and sharing scientific documents and images on the blockchain at a reasonable cost for the users. CONCLUSION: INNBC DApp represents a real use case for blockchain technology in decentralizing biomedical data storage and sharing, providing us with features such as immutability, timestamp, and identity that can be used to ensure permanent availability of the data and to provide proof-of-existence as well as to protect authorship, a freely available decentralized science (DeSci) tool aiming to help bring mass adoption of blockchain technology among the scientific community.

Biagio Boi, Christian Esposito, Jung Taek Seo

Hardware-based solutions are becoming more and more popular as a result of the increased need for practical and safe authentication methods. However, one of the key challenges in these systems is the lack of a robust mechanism to revoke compromised credentials effectively. The Ethereum Attestation Service (EAS), which uses the blockchain-based Ethereum platform to create a decentralized, tamper-resistant infrastructure for credential attestation and revocation, is presented in this article as a novel solution to this critical issue. By combining the transparency and immutability of blockchain technology with smart contracts and cryptographic techniques, the EAS enables secure and auditable management of certificates. The conducted study investigates the limitations of existing revocation methods of password-less mechanisms and proposes the EAS as a viable alternative. In the design phase, the paper demonstrates the system's efficiency in handling attestation requests, verifying attestations, and securely managing revocations. EAS excels in providing reliable revocation, thereby reducing the risks associated with compromised hardware-based passwordless systems. Moreover, this research explores the benefits of EAS-based revocation within the IoT context, where Physically Unclonable Functions (PUFs) face similar challenges as HSMs. Experimental results, obtained in a testnet environment, reveal reduced authentication times, making this solution suitable for real-time scenarios as well.

Anne M. Luescher, Andreas L. Gimpel, Wendelin J. Stark, Reinhard Heckel · 5 authors

Abstract Physical unclonable functions (PUFs) based on unique tokens generated by random manufacturing processes have been proposed as an alternative to mathematical one-way algorithms. However, these tokens are not distributable, which is a disadvantage for decentralized applications. Finding unclonable, yet distributable functions would help bridge this gap and expand the applications of object-bound cryptography. Here we show that large random DNA pools with a segmented structure of alternating constant and randomly generated portions are able to calculate distinct outputs from millions of inputs in a specific and reproducible manner, in analogy to physical unclonable functions. Our experimental data with pools comprising up to >10 10 unique sequences and encompassing >750 comparisons of resulting outputs demonstrate that the proposed chemical unclonable function (CUF) system is robust, distributable, and scalable. Based on this proof of concept, CUF-based anti-counterfeiting systems, non-fungible objects and decentralized multi-user authentication are conceivable.

Dechao Kong, Xiaoqi Li, Wenkai Li

Non-Fungible Tokens (NFTs) are digital assets recorded on the blockchain, providing cryptographic proof of ownership over digital or physical items. Although Solana has only begun to gain popularity in recent years, its NFT market has seen substantial transaction volumes. In this paper, we conduct the first systematic research on the characteristics of Solana NFTs from two perspectives: longitudinal measurement and wash trading security audit. We gathered 132,736 Solana NFT from Solscan and analyzed the sales data within these collections. Investigating users' economic activity and NFT owner information reveals that the top users in Solana NFT are skewed toward a higher distribution of purchases. Subsequently, we employ the Local Outlier Factor algorithm to conduct a wash trading audit on 2,175 popular Solana NFTs. We discovered that 138 NFT pools are involved in wash trading, with 8 of these NFTs having a wash trading rate exceeding 50%. Fortunately, none of these NFTs have been entirely washed out.

Venkata K. V. V. Bathalapalli, Saraju P. Mohanty, Elias Kougianos, Vasanth Iyer · 5 authors

This article presents a novel hardware-assisted distributed ledger-based solution for simultaneous device and data security in smart healthcare. This article presents a novel architecture that integrates PUF, blockchain, and Tangle for Security-by-Design (SbD) of healthcare cyber-physical systems (H-CPSs). Healthcare systems around the world have undergone massive technological transformation and have seen growing adoption with the advancement of Internet-of-Medical Things (IoMT). The technological transformation of healthcare systems to telemedicine, e-health, connected health, and remote health is being made possible with the sophisticated integration of IoMT with machine learning, big data, artificial intelligence (AI), and other technologies. As healthcare systems are becoming more accessible and advanced, security and privacy have become pivotal for the smooth integration and functioning of various systems in H-CPSs. In this work, we present a novel approach that integrates PUF with IOTA Tangle and blockchain and works by storing the PUF keys of a patient's Body Area Network (BAN) inside blockchain to access, store, and share globally. Each patient has a network of smart wearables and a gateway to obtain the physiological sensor data securely. To facilitate communication among various stakeholders in healthcare systems, IOTA Tangle's Masked Authentication Messaging (MAM) communication protocol has been used, which securely enables patients to communicate, share, and store data on Tangle. The MAM channel works in the restricted mode in the proposed architecture, which can be accessed using the patient's gateway PUF key. Furthermore, the successful verification of PUF enables patients to securely send and share physiological sensor data from various wearable and implantable medical devices embedded with PUF. Finally, healthcare system entities like physicians, hospital admin networks, and remote monitoring systems can securely establish communication with patients using MAM and retrieve the patient's BAN PUF keys from the blockchain securely. Our experimental analysis shows that the proposed approach successfully integrates three security primitives, PUF, blockchain, and Tangle, providing decentralized access control and security in H-CPS with minimal energy requirements, data storage, and response time.

Mariem Turki, Bouthaina Dammak, Amnah Alshahrani

Smart Parking Systems have emerged as a transformative solution to address the growing challenges associated with urbanization and increasing vehicular traffic. Such system integrates sensors, cameras, and other IoT connected devices to monitor parking spaces in real time. However, there are many security vulnerabilities in existing solutions, especially when it comes to car authentication at parking entry points. IoT sensors my be susceptible to Cyber-attacks and fraudulent activities, such as car theft, can exploit these vulnerabilities due to limited built-in security features. The reliability of authentication systems, based on IoT sensors can also be compromised by factors such as extreme weather conditions and physical damage. The cyber-physical solution we propose relies on Physical Unclonable Functions (PUFs) for identification and authentication in IoT devices to mitigate these challenges. The use of PUFs enhances the reliability and security of smart parking systems against unauthorized access and fraud. Furthermore, to ensure the integrity and confidentiality of the data within the smart parking ecosystem and to improve authentication process, we propose the implementation of a tailored blockchain framework. This framework incorporates lightweight local blockchains dedicated to individual parking slots, complemented by a central blockchain that manages data at the city level. The experimental results demonstrate the feasibility of the PUF computation process, showcasing an acceptable runtime for practical implementation. In the experimental results, we evaluated the SRAM used for the PUF implementation process and demonstrated its stability (intra HD equals to 2.25.

Dahong Qian, Yiyang Xu, Yuncong Hu

No abstract is available for this record.

Aurélien Boeuf, Anne Canteaut, Léo Perrin

Motivated by progress in the field of zero-knowledge proofs, so-called Arithmetization-Oriented (AO) symmetric primitives have started to appear in the literature, such as MiMC, Poseidon or Rescue. Due to the design constraints implied by this setting, these algorithms are defined using simple operations over large (possibly prime) fields. In particular, many rely on simple low-degree monomials for their non-linear layers, essentially using x ↦ x3 as an S-box.In this paper, we show that the structure of the material injected in each round (be it subkeys in a block cipher or round constants in a public permutation) could allow a specific pattern, whereby a well-defined affine space is mapped to another by the round function, and then to another, etc. Such chains of one-dimensional subspaces always exist over 2 rounds, and they can be extended to an arbitrary number of rounds, for any linear layer, provided that the round-constants are well chosen.As a consequence, for several ciphers like Rescue, or a variant of AES with a monomial Sbox, there exist some round-key sequences for which the cipher has an abnormally high differential uniformity, exceeding the size of the Sbox alphabet.Well-known security arguments, in particular based on the wide-trail strategy, have been reused in the AO setting by many designers. Unfortunately, our results show that such a traditional study may not be sufficient to guarantee security. To illustrate this, we present two new primitives (the tweakable block cipher Snare and the permutation-based hash function Stir) that are built using state-of-the-art security arguments, but which are actually deeply flawed. Indeed, the key schedule of Snare ensures the presence of a subspace chain that significantly simplifies an algebraic attack against it, and the round constants of Stir force the presence of a subspace chain aligned with the rate and capacity of the permutation. This in turns implies the existence of many easy-to-find solutions to the so-called CICO problem.

M. Kiran, Biplob Ray, Jahan Hassan, Aman Kashyap · 5 authors

No abstract is available for this record.