Local reduction and the algebraic cryptanalysis of the block cipher gost

In our constribution we explore a combination of local reduction with the method of syllogisms and the applications of generic guessing strategies in the cryptanalysis of the block cipher GOST. Our experiments show that GOST with 64/128/256 bit key requires at least 12/16/22 rounds to achieve full bit security against the method of syllogisms combined with the ??maximum impact?? strategy.