Unlike Bitcoin, Monero doesn't use a public ledger saying where every coin is, allowing users a greater degree of anonymity.
North Korea has been accused of hacking server networks to install mining scripts for the Monero cryptocurrency. A new Monero mining hacker group has been seizing control of servers over the past year. It's now been linked back to North Korea.
A spin-off of the Lazarus Group - a hacking organisation which cybersecurity researchers have linked to North Korea - is developing malware as a method of generating money rather than stealing data.
The hacking unit, called Andariel, penetrated a server at a South Korean company last summer and used it to mine a cryptocurrency called Monero.
Monero is privacy-oriented and easier to conceal than more mainstream alternatives such as Bitcoin and Ethereum. These qualities make it attractive to hacking groups looking to either steal or surreptitiously mine large quantities of cryptocash. Andariel obtained control of the target server without its real owners noticing.
According to Bloomberg, Kwak Kyoung-ju, the head of a cybersecurity analysis group at the South Korean government-backed Financial Security Institute, said Andariel used the server to generate around 70 Monero coins or roughly $25,000 (£18,400).
The news comes as reports surface of North Korea turning to cryptocurrencies as a source of funding for the government at a time when international sanctions against the reclusive state are tightening.