The Cybersecurity and Infrastructure Security Agency (CISA) is aware of active exploitation of SolarWinds Orion Platform software versions 2019.4 HF 5 through 2020.2.1 HF 1, released between March 2020 and June 2020.
CISA encourages affected organizations to read the SolarWinds and FireEye advisories for more information and FireEye’s GitHub page for detection countermeasures:
SolarWinds Security Advisory
FireEye Advisory: Highly Evasive Attacker Leverages SolarWinds Supply Chain to Compromise Multiple Global Victims With SUNBURST Backdoor
FireEye GitHub page: Sunburst Countermeasures
https://us-cert.cisa.gov/ncas/current-activity/2020/12/13/active-exploitation-solarwinds-software