Paper 2010/532
A 3-Subset Meet-in-the-Middle Attack: Cryptanalysis of the Lightweight Block Cipher KTANTAN
Andrey Bogdanov and Christian Rechberger
Abstract
In this paper we describe a variant of existing meet-in-the-middle attacks on block ciphers. As an application, we propose meet-in-the-middle attacks that are applicable to the full 254-round KTANTAN family of block ciphers accepting a key of 80 bits. The attacks are due to some weaknesses in its bitwise key schedule. We report an attack of time complexity 2^75.170 encryptions on the full KTANTAN32 cipher with only 3 plaintext/ciphertext pairs and well as 2^75.044 encryptions on the full KTANTAN48 and 2^75.584 encryptions on the full KTANTAN64 with 2 plaintext/ciphertext pairs. All these attacks work in the classical attack model without any related keys. In the differential related-key model, we demonstrate 218- and 174-round differentials holding with probability 1. This shows that a strong related-key property can translate to a successful attack in the non-related-key setting. Having extremely low data requirements, these attacks are valid even in RFID-like environments where only a very limited amount of text material may be available to an attacker.
Note: Fixed typos and extended acknowledgements.
Metadata
- Available format(s)
-
PDF
- Category
- Secret-key cryptography
- Publication info
- Published elsewhere. An extended version of the paper accepted for SAC 2010
- Keywords
- cryptanalysismeet-in-the-middle attacksblock cipherkey schedulelightweight cipherkey-recoveryRFID
- Contact author(s)
-
and bogdanov @ googlemail com
christian rechberger @ groestl info - History
- 2011-02-14: revised
- 2010-10-19: received
- See all versions
- Short URL
- https://ia.cr/2010/532
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2010/532,
author = {Andrey Bogdanov and Christian Rechberger},
title = {A 3-Subset Meet-in-the-Middle Attack: Cryptanalysis of the Lightweight Block Cipher {KTANTAN}},
howpublished = {Cryptology {ePrint} Archive, Paper 2010/532},
year = {2010},
url = {https://eprint.iacr.org/2010/532}
}
