Researcher Troy Mursch published a report showing how he identified around 50,000 WordPress websites used to extract cryptocurrencies. For this purpose, the resources of the visitors' CPUs are used without their realizing it. The cryptocurrency mainly mined is Monero.
To identify these sites, the researcher used the PublicWWW search engine, a tool that indexes the source code. Then he looked for the main mining scripts such as Coinhive, Crypto-Loot, CoinImp and deepMiner.