Microsoft and Industry Partners Seize Key Domain Used In SolarWinds Hack

An anonymous reader quotes a report from ZDNet: Microsoft and a coalition of tech companies have intervened today to seize and sinkhole a domain that played a central role in the SolarWinds hack, ZDNet has learned from sources familiar with the matter. The domain in question is avsvmcloud[.]com, which served as command and control (C&C) server for malware delivered to around 18,000 SolarWinds customers via a trojanized update for the company’s Orion app. SolarWinds Orion updates versions 2019.4 through 2020.2.1, released between March 2020 and June 2020, contained a strain of malware named SUNBURST (also known as Solorigate). Once installed on a computer, the malware would sit dormant for 12 to 14 days and then ping a subdomain of avsvmcloud[.]com. According to analysis from security firm FireEye, the C&C domain would reply with a DNS response that contained a CNAME field with information on another domain from where the SUNBURST malware would obtain further instructions and additional payloads to execute on an infected company’s network. Earlier today, a coalition of tech companies seized and sinkholed avsvmcloud[.]com, transferring the domain into Microsoft’s possession. Sources familiar with today’s actions described the takedown as “protective work” done to prevent the threat actor behind the SolarWinds hack from delivering new orders to infected computers.