According to local news Agency, in China police arrested 20 employees of computer firms on suspicion that they are acting in collusion for the purpose of personal enrichment has extended the covert mining of more than one million computers.
The attackers created and deployed malicious software in browser plugins, for example, to «increase Internet speed». Then promote these plugins through the ad network, which had 5 million users.
Once the victim has installed this plugin, it infected the computer and the program covert mining started. According to police, all were infected over a million computers within two years was producing such crypto-currencies like Digibyte, Decred and Siacoin. The choice was due to the fact that their production was not required a lot of computing power, allowing background mining has been less visible to the victims of hacking. The most conservative estimate, sold coins brought the attackers more than two million dollars.
In addition, attackers managed to create a kind of irregular network, where they had over 100 agents promoting the program through their working relationship — for example, in Internet cafes, as in the recent case, which also happened in China when attackers managed to infect more than 100,000 computers.