Decoy Dog is a malware toolkit based on pupy that uses DNS to communicate.
https://insights.infoblox.com/resources-report/infoblox-report-decoy-dog-is-no-ordinary-pupy-distinguishing-malware-via-dns https://blogs.infoblox.com/threat-intelligence/decoy-dog-is-no-ordinary-pupy-distinguishing-malware-via-dns/