Date Added: May 2011
In this paper, the authors describe the first single-key attack which can break the full version of Grain-128 for arbitrary keys by an algorithm which is considerably faster than exhaustive search. It uses a new version of a cube tester, which uses an improved choice of dynamic variables to eliminate all the previously made assumptions on the key, to speed up the attack, and to simplify the final key recovery. Since it is extremely difficult to mathematically analyze the expected behavior of such attacks, they implemented it on RIVYERA, which is a new massively parallel reconfigurable hardware, and tested its main components for dozens of random keys. These tests experimentally verified the correctness and expected complexity of the attack.