Аннотация: The article is devoted to an overview of SHA hashing algorithms in cryptocurrencies, which are currently very relevant. This article gives the basic concepts of hashing algorithms in cryptocurrencies and the principles of their operation, discusses hash functions used in modern digital currencies, and explains the relevance of SHA and its types, as well as the development of the SHA family of algorithms in cryptography, the goals and reasons for using this algorithm in cryptocurrencies. The purpose of this article is to identify the main digital currencies that use SHA hashing algorithms, the advantage of using it, and how relevant and secure its transactions in currencies are. There has been also done an indication of the effectiveness of using the SHA algorithm in currencies. Based on the analyzed data, the conclusion is made of the features of the use of this algorithm in cryptography and in cryptocurrencies, vulnerabilities that can be observed. The article also examines possible attacks on blockchain and crypto wallets, systematizes and identifies the main ways to combat them, as well as ways to protect.