Publications related to On the Pseudorandom Function Assumption in (Secure) Distance-Bounding Protocols

On the Theory and Practice of Modern Secure Messaging

Billions of people now have conversations daily over the Internet. A large portion of this communication takes place via secure messaging protocols that offer "end-to-end encryption'" guarantees and resilience to compromise like the widely-used Double Ratc ...

EPFL2024

Side-channel analysis of isogeny-based key encapsulation mechanisms and hash-based digital signatures

Aymeric Genet

Current cryptographic solutions will become obsolete with the arrival of large-scale universal quantum computers. As a result, the National Institute of Standards and Technology supervises a post-quantum standardization process which involves evaluating ca ...

EPFL2024

Anonymous Tokens with Stronger Metadata Bit Hiding from Algebraic MACs

Serge Vaudenay, Fatma Betül Durak

On the one hand, the web needs to be secured from malicious activities such as bots or DoS attacks; on the other hand, such needs ideally should not justify services tracking people's activities on the web. Anonymous tokens provide a nice tradeoff between ...

2023

A review of the security vulnerabilities and countermeasures in the Internet of Things solutions: A bright future for the Blockchain

Jan Van Herle, Hossein Pourrahmani

The current advances in the Internet of Things (IoT) and the solutions being offered by this technology have accounted IoT among the top ten technologies that will transform the global economy by 2030. IoT is a state-of-the-art paradigm that has developed ...

2023

Revisiting the Indifferentiability of the Sum of Permutations

Ritam Bhaumik

The sum of two n-bit pseudorandom permutations is known to behave like a pseudorandom function with n bits of security. A recent line of research has investigated the security of two public n-bit permutations and its degree of indifferentiability. Mandal e ...

Springer2023

The Side-channel Metrics Cheat Sheet

Francesco Regazzoni, Mirjana Stojilovic, Dorian Ros, Ognjen Glamocanin

Side-channel attacks exploit a physical observable originating from a cryptographic device in order to extract its secrets. Many practically relevant advances in the field of side-channel analysis relate to security evaluations of cryptographic functions a ...

2023

Modelling and design of CMOS SPAD sensors for quantum random number generation

Pouyan Keshavarzian

Modern digital connectivity has necessitated the creation of robust methods for securely storing and transferring data. At the heart of all security infrastructure is the random number generator (RNG). While random numbers find use in a variety of applicat ...

EPFL2023

Public-Key Encryption with Quantum Keys

Khashayar Barooti

In the framework of Impagliazzo's five worlds, a distinction is often made between two worlds, one where public-key encryption exists (Cryptomania), and one in which only one-way functions exist (MiniCrypt). However, the boundaries between these worlds can ...

Springer International Publishing Ag2023

EOS: Efficient Private Delegation of zkSNARK Provers

Yinuo Zhang, Alessandro Chiesa

Succinct zero knowledge proofs (i.e. zkSNARKs) are powerful cryptographic tools that enable a prover to convince a verifier that a given statement is true without revealing any additional information. Their attractive privacy properties have led to much ac ...

Usenix Assoc2023

A 3.3-Gb/s SPAD-Based Quantum Random Number Generator

Edoardo Charbon, Francesco Gramuglia, Pouyan Keshavarzian, Mario Stipcevic

Quantum random number generators (QRNGs) are a burgeoning technology used for a variety of applications, including modern security and encryption systems. Typical methods exploit an entropy source combined with an extraction or bit generation circuit in or ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2023

Cryptographic Administration for Secure Group Messaging

Serge Vaudenay, Daniel Patrick Collins

Many real-world group messaging systems delegate group administration to the application level, failing to provide formal guarantees related to group membership. Taking a cryptographic approach to group administration can prevent both implementation and pr ...

Berkeley2023

Toward Mobile Distributed Ledgers

Boi Faltings, Sujit Prakash Gujar, Dimitrios Chatzopoulos, Anurag Jain

Advances in mobile computing have paved the way for new types of distributed applications that can be executed solely by mobile devices on Device-to-Device (D2D) ecosystems (e.g., crowdsensing). Sophisticated applications, like cryptocurrencies, need distr ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Optimal Symmetric Ratcheting for Secure Communication

Serge Vaudenay, Andrea Felice Caforio, Daniel Patrick Collins, Hailun Yan

To mitigate state exposure threats to long-lived instant messaging sessions, ratcheting was introduced, which is used in practice in protocols like Signal. However, existing ratcheting protocols generally come with a high cost. Recently, Caforio et al. pro ...

OXFORD UNIV PRESS2022

PROFACTORY: Improving IoT Security via Formalized Protocol Customization

Fei Wang, Mathias Josef Payer, Xiangyu Zhang, Duo Xu

As IoT applications gain widespread adoption, it becomes important to design and implement IoT protocols with security. Existing research in protocol security reveals that the majority of disclosed protocol vulnerabilities are caused by incorrectly impleme ...

USENIX ASSOC2022

Analysis and Improvements of the Sender Keys Protocol for Group Messaging

Daniel Patrick Collins

Messaging between two parties and in the group setting has enjoyed widespread attention both in practice, and, more recently, from the cryptographic community. One of the main challenges in the area is constructing secure (end-to- end encrypted) and effici ...

2022

Blockchain-based Practical Multi-agent Secure Comparison and its Application in Auctions

Boi Faltings, Sujit Prakash Gujar, Sankarshan Damle

AI applications find widespread use in a variety of domains. For further acceptance, mostly when multiple agents interact with the system, we must aim to preserve the privacy of participants information in such applications. Towards this, the Yao’s Million ...

ACM2022

BLURtooth: Exploiting Cross-Transport Key Derivation in Bluetooth Classic and Bluetooth Low Energy

Mathias Josef Payer, Daniele Antonioli

Bluetooth is a pervasive wireless technology specified in an open standard. The standard defines Bluetooth Classic (BT) for high-throughput wireless services and Bluetooth Low Energy (BLE) very low-power ones. The standard also specifies security mechanism ...

ASSOC COMPUTING MACHINERY2022

Protecting privacy through metadata analysis

Sandra Deepthy Siby

Although encryption hides the content of communications from third parties, metadata, i.e., the information attached to the content (such as the size or timing of communication) can be a rich source of details and context. In this dissertation, we demonstr ...

EPFL2022

Beyond Security and Efficiency: On-Demand Ratcheting with Security Awareness

Serge Vaudenay, Andrea Felice Caforio, Fatma Betül Durak

Secure asynchronous two-party communication applies ratcheting to strengthen privacy, in the presence of internal state exposures. Security with ratcheting is provided in two forms: forward security and post-compromise security. There have been several suc ...

2021

Integrity and Metadata Protection in Data Retrieval

Kirill Nikitin

Secure retrieval of data requires integrity, confidentially, transparency, and metadata-privacy of the process. Existing protection mechanisms, however, provide only partially these properties: encryption schemes still expose cleartext metadata, protocols ...

EPFL2021