The European Union Police Service published an annual report on cybercrime, which reports an increase in the use of Zcash, Monero and Ether crypto currency in the implementation of illegal transactions in darknet. This is reported by the report prepared by Europol IOCTA 2017.
As noted in the document, despite the widespread use of bitcoin by cybercriminals, various altcoins are rapidly gaining popularity in the digital underground, including Ethereum and Zcash. Europol noted the Monero (XMR), which its popularity is largely due to "additional security and confidentiality functions."
The Europol report talks about the growing popularity of crypto-currencies on anonymous darknet platforms, as well as the Kirk, who claims for ransom in Monero. The document also says that darknet platforms can be created on the basis of Ethereum blockchain, and smart contracts can be used to pay for illegal goods.
As for the Zcash crypto currency, Europol does not mention any specific cases of its illegal use. At the same time, due to confidentiality and the ability to "hide both the transaction recipient and the amount," there is a growing interest among darkweb marketplaces from this anonymous cryptocurrency.
It should be noted, however, that contrary to the position of Europol, the Zcash project is a partner of The Blockchain Alliance forum, one of the main goals of which is to counteract cybercrime and the spread of malicious software.