Necurs botnet

Reports

Around June 1, 2016, the botnet went offline, perhaps due to a glitch in the command and control server. However, three weeks later, Jon French from AppRiver discovered a spike in spam emails, signifying either a temporary spike in the botnet's activity or return to its normal pre-June 1 state. In late March, 2017, the botnet began to send spam emails as part of a pump and dump scam.

Distributed malware