CISA Issues Emergency Directive 21-01 for SolarWinds Orion Compromise
On December 13, 2020 CISA ordered federal civilian agencies to disconnect vulnerable SolarWinds Orion instances under Emergency Directive 21-01 after a nation-state supply-chain attack implanted the SUNBURST backdoor across Orion builds released between March and June 2020.
Executive briefing: The Cybersecurity and Infrastructure Security Agency (CISA) issued Emergency Directive 21-01 on requiring federal agencies to immediately disconnect and forensically triage affected SolarWinds Orion systems. The directive responded to FireEye’s disclosure of the SUNBURST backdoor, which allowed authenticated remote code execution across Orion application servers.
Containment requirements
- Immediate disconnect. Agencies had to power down Orion servers, block all traffic to and from SolarWinds domains, and preserve system images for investigation.
- Incident reporting. CISA mandated completion of incident response surveys and submission of forensic artifacts within 12 hours of discovery.
- Hunting guidance. The directive referenced malware analysis and IOCs that defenders needed to deploy across enterprise monitoring stacks.
Enterprise actions
- Inventory Orion usage across on-premises and hosted environments, ensuring service accounts and network paths tied to the platform remain disabled until patched builds are redeployed.
- Deploy network and endpoint detections using the CISA-provided Snort rules, YARA signatures, and forensic hunting queries.
- Update third-party risk registers and supplier due diligence workflows to capture tampering risks in software build pipelines.
Follow-up: The directive was closed in 2021 after federal agencies re-imaged SolarWinds assets, and CISA’s Known Exploited Vulnerabilities catalog plus the 2023 Secure by Design pledge now carry the supply-chain lessons into routine vulnerability management.
Sources
- CISA Emergency Directive 21-01 — cisa.gov; Emergency Directive ordering agencies to disconnect SolarWinds Orion platforms and follow specified incident response actions.
- FireEye Blog — Highly Evasive Attacker Leverages SolarWinds Supply Chain to Compromise Multiple Global Victims — mandiant.com; FireEye’s original disclosure detailing the SUNBURST backdoor, malicious update process, and post-compromise tradecraft.