## Cryptology ePrint Archive: Report 2016/743

Investigating Cube Attacks on the Authenticated Encryption Stream Cipher ACORN

Md Iftekhar Salam and Harry Bartlett and Ed Dawson and Josef Pieprzyk and Leonie Simpson and Kenneth Koon-Ho Wong

Abstract: The cube attack is an algebraic attack that allows an adversary to extract low degree polynomial equations from the targeted cryptographic primitive. This work applies the cube attack to a reduced round version of ACORN, a candidate cipher design in the CAESAR cryptographic competition. The cube attack on 477 initialization rounds of ACORN can recover the 128 bit key with a total attack complexity of about $2^{35}$. We have also shown that linear equations relating the initial state of the full version of ACORN can be be easily generated which can lead to state recovery attack with an attack complexity of about $2^{72.8}$.

Category / Keywords: secret-key cryptography / CAESAR, Authenticated Encryption, Cube Attack, ACORN, AEAD, Confidentiality

Date: received 29 Jul 2016, last revised 29 Jul 2016

Contact author: m salam at qut edu au

Available format(s): PDF | BibTeX Citation

Short URL: ia.cr/2016/743

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