Microsoft has confirmed the latest evolution of the Kelihos botnet is on its radar, suggesting that a renewed takedown effort may be on the cards. From V3:

The evolved botnet is more dangerous than previous versions as it features so-called fast-flux capabilities, which make it harder for security firms to identify the command and control servers.

Kaspersky has since linked the new Kelihos botnet to the Nap Trojan discovered by security firm FireEye last week.

Microsoft had claimed to have taken down the botnet down by sinkholing the domains that Kelihos was using in 2011.

 Microsoft confirms Kelihos botnet return on its radar