PushDo has added a new botnet recovery technique capable of defeating earlier takedown strategies. The PushDo malware has borrowed a resiliency feature previously encountered in malware, such as Bobax, Sinowal, and Murofet. The technique forms the fallback mechanism should the original, “hard coded” command-and-control (C&C) be taken down. A minor tweak of the algorithm undoes much of the actionable intelligence that had previously been extracted from a captured PushDo sample.”]
Source: https://www.darkreading.com/attacks-breaches/much-ado-about-pushdo