Microsoft and other vendors are quickly moving to block the Sunburst backdoor used in the attack. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has warned that SolarWinds may not be alone in its use in the campaign. FireEye has identified a kill switch for the malware, and Microsoft has begun blocking the versions of the updates containing the malicious binary, known as the Sunburst backdoor, and, FireEye have also found a killswitch.
Source: https://threatpost.com/solarwinds-default-password-access-sales/162327/