It is crucial for a cipher to be trusted that its design be wellexplained. However, some designers do not publish their design methodand instead merely put forward a specification. While this information issufficient for implementers, the lack of explanation hinders third partycryptanalysis.In a recent string of papers, Biryukov, Perrin and Udovenko identifiedincreasingly strong patterns in a subcomponent shared by the last twoRussian standards in symmetric cryptography, namely the hash functionStreebog (GOST R 34.11-2012) and the block cipher Kuznyechik (GOSTR 34.12-2015). In this paper, we summarize the latest result of Perrinon this topic and argue that, in light of them, these algorithms must beavoided.