Concept

Meet-in-the-middle attack

Publications associées (16)

Compact Circuits for Combined AES Encryption/Decryption

The implementation of the AES encryption core by Moradi et al. at Eurocrypt 2011 is one of the smallest in terms of gate area. The circuit takes around 2400 gates and operates on an 8 bit datapath. However this is an encryption only core and unable to cate ...

2019

Cryptanalysis of Plantlet

Subhadeep Banik, Khashayar Barooti

Plantlet is a lightweight stream cipher designed by Mikhalev, Armknecht and Muller in IACR ToSC 2017. It has a Grain-like structure with two state registers of size 40 and 61 bits. In spite of this, the cipher does not seem to lose in security against gene ...

2019

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

Cryptanalysis of Enhanced MORE

Serge Vaudenay, Damian Vizár

Fully homomorphic encryption (FHE) has been among the most popular research topics of the last decade. While the bootstrapping-based, public key cryptosystems that follow Gentry's original design are getting more and more efficient, their performance is st ...

2018

Generic Round-Function-Recovery Attacks for Feistel Networks over Small Domains

Serge Vaudenay, Fatma Betül Durak

Feistel Networks (FN) are now being used massively to encrypt credit card numbers through format-preserving encryption. In our work, we focus on FN with two branches, entirely unknown round functions, modular additions (or other group operations), and when ...

2018

Generic Round-Function-Recovery Attacks for Feistel Networks over Small Domains

Serge Vaudenay, Fatma Betül Durak

ePrint2018

Provably Secure Authenticated Encryption

Damian Vizár

Authenticated Encryption (AE) is a symmetric key cryptographic primitive that ensures confidentiality and authenticity of processed messages at the same time. The research of AE as a primitive in its own right started in 2000. The security goals of AE wer ...

EPFL2018

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

Authenticated Encryption with Variable Stretch

Serge Vaudenay, Damian Vizár, Reza Reyhanitabar

In conventional authenticated-encryption (AE) schemes, the ciphertext expansion, a.k.a.stretch or tag length, is a constant or a parameter of the scheme that must be fixed per key. However, using variable-length tags per key can be desirable in practice or ...

Springer-Verlag Berlin2016

On the Key Schedule of Lightweight Block Ciphers

Serge Vaudenay, Jialin Huang

Key schedules in lightweight block ciphers are often highly simplified, which causes weakness that can be exploited in many attacks. Today it remains an open problem on how to use limited operations to guarantee enough diffusion of key bits in lightweight ...

Springer-Verlag Berlin2014

Bounded Tamper Resilience: How to go beyond the Algebraic Barrier

Sebastian Faust

Related key attacks (RKAs) are powerful cryptanalytic attacks where an adversary can change the secret key and observe the effect of such changes at the output. The state of the art in RKA security protects against an a-priori unbounded number of certain a ...

2013

A Related-Key Attack against Multiple Encryption based on Fixed Points

Serge Vaudenay, Atefeh Mashatan, Asli Bay

In order to alleviate the burden of short keys, encrypting a multiple times has been proposed. In the multiple encryption mode, there may be encryptions under the same or different keys. There have been several attacks against this encryption mode. When tr ...

Springer2011

Related-Key Attack against Triple Encryption based on Fixed Points

Serge Vaudenay

Triple encryption was proposed to increase the security of single encryption when the key is too short. In the past, there have been several attacks in this encryption mode. When triple encryption is based on two keys, Merkle and Hellman proposed a subtle ...

SciTePress2011

Algebraic, AIDA/Cube and Side Channel Analysis of KATAN Family of Block Ciphers

Pouyan Sepehrdad, Jorge Nakahara

This paper presents the first results on AIDA/cube, algebraic and side-channel attacks on variable number of rounds of all members of the KATAN family of block ciphers. Our cube attacks reach 60, 40 and 30 rounds of KATAN32, KATAN48 and KATAN64, respective ...

Springer2010

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