The article deals with the peculiarities of suspicious transactions in financial markets related to the use of cryptocurrencies, it also studies current issues regarding the classification of virtual assets. The features of countering suspicious transactions in financial markets associated with the use of cryptocurrency are highlighted. Topical issues of taxonomy of virtual assets and risk assessment of service providers' activities in assessing the risk of operations with virtual assets related to their use in legalization operations are investigated. The concepts of regulation of virtual assets are considered. The concept of mining, the problem of the relationship of varieties of mining activity to the classification of certain types of activity, its legalization are defined, and recommendations for the classification of mining activities are given. The relationship between miners, validators and virtual asset providers (VASP) in the event of a cyberattack or in the presence of certain rights to the network has been analyzed, which leads to the classification of this type of activity as risky regarding the use of cryptocurrencies with criminal intent. It is also underlined the need to introduce a risk-based approach to countering money laundering and terrorist financing (AML / CFT) by national state supervisory and law enforcement agencies, enterprises involved in the virtual asset market, preventing threats and developing a legislative framework for regulation the crypto market and interaction on these issues at the international level.