Faster multicollisions attack on sponge construction

Abstract

Multicollision attacks are sophisticated attacks that are analyzed in cryptographic hash functions. Previous works on multicollision have reported that the technique of determining the t-collisions where t > 2 is no more difficult than that of identifying the 2-collisions. Kelsey and Schneier have improved the technique by using a fixed point to locate the multicollision with the complexity of 3.2n/2. Aumasson has developed a new attack known as the faster multicollision based on the Kelsey and Schneier attacks and implemented it in the Merkle-Damgård construction with a complexity of 2n/2. However, this technique has never been applied to the sponge construction. In this paper, a recent multicollision attack is applied on sponge construction and we found that the sponge construction has no resistance against such attacks when c = n. © 2017 American Scientific Publishers All rights reserved.