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Concept

Ciphertext-only attack

Publications associées (25)

Analyzing and Protecting Communication Metadata

Ludovic Barman

Most communication systems (e.g., e-mails, instant messengers, VPNs) use encryption to prevent third parties from learning sensitive information. However, encrypted communications protect the contents but often leak metadata: the amount of data sent and th ...

EPFL2021

Cryptanalysis of LowMC instances using single plaintext/ciphertext pair

Serge Vaudenay, Subhadeep Banik, Fatma Betül Durak, Khashayar Barooti

Arguably one of the main applications of the LowMC family ciphers is in the post-quantum signature scheme PICNIC. Although LowMC family ciphers have been studied from a cryptanalytic point of view before, none of these studies were directly concerned with ...

2020

Can Caesar Beat Galois?

Serge Vaudenay, Damian Vizár

The Competition for Authenticated Encryption: Security, Applicability and Robustness (CAESAR) has as its official goal to “identify a portfolio of authenticated ciphers that offer advantages over [the Galois-Counter Mode with AES]” and are suitable for wid ...

2018

The Hidden Vulnerability of Distributed Learning in Byzantium

Rachid Guerraoui, El Mahdi El Mhamdi, Sébastien Louis Alexandre Rouault

While machine learning is going through an era of celebrated success, concerns have been raised about the vulnerability of its backbone: stochastic gradient descent (SGD). Recent approaches have been proposed to ensure the robustness of distributed SGD aga ...

2018

Breaking The FF3 Format-Preserving Encryption Standard Over Small Domains

Serge Vaudenay, Fatma Betül Durak

The National Institute of Standards and Technology (NIST) recently published a Format-Preserving Encryption standard accepting two Feistel structure based schemes called FF1 and FF3. Particularly, FF3 is a tweakable block cipher based on an 8-round Feistel ...

2017

Breaking the FF3 Format Preserving Encryption

Serge Vaudenay, Fatma Betül Durak

The NIST standard FF3 scheme (also known as BPS scheme) is a tweakable block cipher based on a 8-round Feistel Network. We break it with a practical attack. Our attack exploits the bad domain separation in FF3 design. The attack works with chosen plaintext ...

2017

On Selection of Samples in Algebraic Attacks and a New Technique to Find Hidden Low Degree Equations

Serge Vaudenay, Pouyan Sepehrdad, Petr Susil

The best way of selecting samples in algebraic attacks against block ciphers is not well explored and understood. We introduce a simple strategy for selecting the plaintexts and demonstrate its strength by breaking reduced-round KATAN, LBLOCK and SIMON. Fo ...

Springer Verlag2016

Protecting against Multidimensional Linear and Truncated Differential Cryptanalysis by Decorrelation

Serge Vaudenay

The decorrelation theory provides a different point of view on the security of block cipher primitives. Results on some statistical attacks obtained in this context can support or provide new insight on the security of symmetric cryptographic primitives. I ...

Springer-Verlag Berlin2015

On Selection of Samples in Algebraic Attacks and a New Technique to Find Hidden Low Degree Equations

Serge Vaudenay, Pouyan Sepehrdad, Petr Susil

Springer-Verlag Berlin2014

Unifying Leakage Models: From Probing Attacks to Noisy Leakage

Alexandre Raphaël Duc, Sebastian Faust

A recent trend in cryptography is to formally show the leakage resilience of cryptographic implementations in a given leakage model. One of the most prominent leakage models -- the so-called bounded leakage model -- assumes that the amount of leakage is a- ...

Springer2014

Proactively Accountable Anonymous Messaging in Verdict

Bryan Alexander Ford, Henry Nathaniel Corrigan-Gibbs

Among anonymity systems, DC-nets have long held attraction for their resistance to traffic analysis attacks, but practical implementations remain vulnerable to internal disruption or “jamming” attacks, which require time-consuming detection procedures to r ...

2013

Resistance against Adaptive Plaintext-Ciphertext Iterated Distinguishers

Serge Vaudenay, Atefeh Mashatan, Asli Bay

Decorrelation Theory deals with general adversaries who are mounting iterated attacks, i.e., attacks in which an adversary is allowed to make d queries in each iteration with the aim of distinguishing a random cipher C from the ideal random cipher C^*. A b ...

2012

Statistical and Algebraic Cryptanalysis of Lightweight and Ultra-Lightweight Symmetric Primitives

Pouyan Sepehrdad

Symmetric cryptographic primitives such as block and stream ciphers are the building blocks in many cryptographic protocols. Having such blocks which provide provable security against various types of attacks is often hard. On the other hand, if possible, ...

EPFL2012

Security and Privacy in RFID Systems

Khaled Ouafi

This PhD thesis is concerned with authentication protocols using portable lightweight devices such as RFID tags. these devices have lately gained a significant attention for the diversity of the applications that could benefit form their features, ranging ...

EPFL2012

An Architecture-Independent Instruction Shuffler to Protect against Side-Channel Attacks

Paolo Ienne, Wayne Burleson, Ali Galip Bayrak, Nikola Velickovic

Embedded cryptographic systems, such as smart cards, require secure implementations that are robust to a variety of low-level attacks. Side-Channel Attacks (SCA) exploit the information such as power consumption, electromagnetic radiation and acoustic leak ...

2012

Statistical Attack on RC4: Distinguishing WPA

Serge Vaudenay, Pouyan Sepehrdad, Martin Vuagnoux

In this paper we construct several tools for manipulating pools of biases in the analysis of RC4. Then, we show that optimized strategies can break WEP based on 4000 packets by assuming that the first bytes of plaintext are known for each packet. We descri ...

Springer2011

New Impossible Differential and Known-Key Distinguishers for the 3D Cipher

Jorge Nakahara

The contributions of this paper are new 6-round impossible-differential (ID) and 9.75-round known-key distinguishers for the 3D block cipher. The former was constructed using the miss-in-the-middle technique, while the latter with an inside-out technique. ...

Springer-Verlag Berlin2011

Analysis and Optimization of Cryptographically Generated Addresses

Jean-Pierre Hubaux, Joppe Willem Bos, Onur Özen

The need for nodes to be able to generate their own address and verify those from others, without relying on a global trusted authority, is a well-known problem in networking. One popular technique for solving this problem is to use self-certifying address ...

Springer-Verlag New York, Ms Ingrid Cunningham, 175 Fifth Ave, New York, Ny 10010 Usa2009

Linear (Hull) and Algebraic Cryptanalysis of the Block Cipher PRESENT

Pouyan Sepehrdad, Jorge Nakahara

The contributions of this paper include the first linear hull and a revisit of the algebraic cryptanalysis of reduced-round variants of the block cipher PRESENT, under known-plaintext and ciphertext- only settings. We introduce a pure algebraic cryptanalys ...

Springer Berlin / Heidelberg2009

Evaluating Resistance of MCML Technology to Power Analysis Attacks Using a Simulation-Based Methodology

Yusuf Leblebici, Paolo Ienne, Francesco Regazzoni, Zeynep Toprak Deniz

This paper explores the resistance of MOS Current Mode Logic (MCML) against attacks based on the observation of the power consumption. Circuits implemented in MCML, in fact, have unique characteristics both in terms of power consumption and the dependency ...

2009