CISA and the Department of Defense (DoD) Cyber National Mission Force (CNMF) have analyzed additional SolarWinds-related malware variants—referred to as SUNSHUTTLE and SOLARFLARE. One of the analyzed files was identified as a China Chopper webshell server-side component that was observed on a network with an active SUNSHUTTLE infection. The webshell can provide a cyber threat actor an alternative method of accessing a network, even if the SUNSHUTTLE infection was remediated.
The U.S. Government attributes this activity to the Russian Foreign Intelligence Service (SVR).
CISA encourages users and administrators to review Malware Analysis Report MAR-10327841-1.v1, U.S. Cyber Command’s VirusTotal page, and the following resources for more information: