ZeroAccess is a Trojan horse computer malware that affects Microsoft Windows operating systems.
Finally, a third infection vector used is an affiliate scheme where third-party persons are paid for installing the rootkit on a system.
[6][7] In December 2013 a coalition led by Microsoft moved to destroy the command and control network for the botnet.
The attack was ineffective though because not all C&C were seized, and its peer-to-peer command and control component was unaffected - meaning the botnet could still be updated at will.
[8] Once a system has been infected with the ZeroAccess rootkit it will start one of the two main botnet operations: bitcoin mining or click fraud.