The Virut botnet was comprised of an estimated 300,000 compromised zombie systems. The botnet’s command-and-control servers were operating from top-level domain names in Poland. The anti-spam group Spamhaus and CERT Poland shut down 23 of those domains. Kaspersky Lab says 5.5% of all viruses detected on infected PCs globally were Virut in the third quarter of 2012. In 2012 for Poland alone, over 890,000 unique IP addresses were reported to be infected by Virut.”]
Source: https://www.darkreading.com/attacks-breaches/virut-malware-botnet-torpedoed-by-security-researchers