For Kuznyechik we performed experiments of searching 240 slide pairs with MPI and special precomputed tables for encryption acceleration. The probability to find a correct key pair comprised 0.34. The time required for a single ex-periment comprised from 167 to 376 hours with a HP cluster with 20 Intel® XeonTM cores working on 1.77 GHz with 10 GB RAM tied with Gigabit Ethernet. The span of times is caused by the fact that the chance of finding a slide pair sooner or later depends on the input data.