Emergency Directive 21-01 Older Supplemental Guidance

Below are previous versions of supplemental guidance that have now been superseded. See Emergency Directive 21-01 for the latest guidance.

Supplemental Guidance v2

Original Release Date: December 30, 2020

This guidance supplements the Emergency Directive (ED) 21-01 and Supplemental Guidance v1 issued on December 18, 2020.

Specifically, all federal agencies operating versions of the SolarWinds Orion platform other than those identified as “affected versions” below are required to use at least SolarWinds Orion Platform version 2020.2.1HF2. The National Security Agency (NSA) has examined this version and verified that it eliminates the previously identified malicious code. Given the number and nature of disclosed and undisclosed vulnerabilities in SolarWinds Orion, all instances that remain connected to federal networks must be updated to 2020.2.1 HF2 by COB December 31, 2020. CISA will follow up with additional supplemental guidance, to include further clarifications and hardening requirements.

Orion Platform Version

Continued use of SolarWinds Orion permitted at this time

Update required?

Affected versions: 2019.4 HF5, 2020.2 RC1, 2020.2 RC2, 2020.2, 2020.2 HF1 (should be powered down or removed from networks based on ED 21-01)



All other versions that are currently online (if the instance did not previously use an affected version)


Yes (2020.2.1HF2)

Supplemental Guidance v1

Original Release Date: December 18, 2020

This section provides additional guidance on the implementation of CISA Emergency Directive (ED) 21-01, to include an update on affected versions, guidance for agencies using third-party service providers, and additional clarity on required actions. On December 13, 2020, CISA issued ED 21-01 to mitigate the SolarWinds Orion Code Compromise. As noted in ED 21-01, CISA continues to work with our partners to monitor for active exploitation associated with this compromise and will continue providing updated guidance to agencies as new information becomes available. ED 21-01 also indicated that agencies must wait until CISA provides further guidance before using any forthcoming patches to reinstall the SolarWinds Orion software in their enterprise. This supplemental guidance is the first in that series of guidance. CISA will continue to provide further guidance as new information becomes available.

ED 21-01 directed agencies to immediately disconnect or power down SolarWinds Orion, versions 2019.4 through 2020.2.1 HF1, from their network. As of this guidance and based on developing information, CISA is dividing this range of versions into two groups: versions that have been identified as containing a malicious backdoor (“affected versions”) and versions that have been identified as not containing that malicious backdoor (“unaffected versions”). ED 21-01 and this guidance also contain instructions relating to versions of SolarWinds Orion outside of this version range (“other versions”).

Affected Versions

The following versions are considered affected versions:

  • Orion Platform 2019.4 HF5, version 2019.4.5200.9083
  • Orion Platform 2020.2 RC1, version 2020.2.100.12219
  • Orion Platform 2020.2 RC2, version 2020.2.5200.12394
  • Orion Platform 2020.2, 2020.2 HF1, version 2020.2.5300.12432

Agencies that were using affected versions at any time prior to the issuance of ED 21-01 must:

  1. Keep these products disconnected as required by ED 21-01 pending further CISA guidance and not rebuild or reimage the affected platforms and host operating systems (OS), including (re)joining the host OS to the enterprise domain, until such time as CISA directs otherwise.
  2. Label and isolate all backups of the affected versions from their systems to prevent accidental re-introduction of malicious code to the production environment.
  3. Conduct forensic analysis or search, as appropriate based on capability, for indicators of compromise (IOCs) or other evidence of threat actor activity.

a. Agencies running affected versions that have no capability to conduct forensic analysis (system memory, host storage, network) shall, at minimum, search for IOCs or other evidence of threat actor activity published in ED 21-01, Activity Alert AA20-352A, and future associated guidance.

b. Agencies that find matches to these IOCs or evidence of threat actor activity through forensics analysis must report this as an incident to CISA through. If a reporting agency already submitted incident information to CISA, please send updates to CISA as you discover new evidence.

c. Agencies running affected versions that have no capability to conduct forensic analysis and no capability to search for IOCs shall assume breach, report the incident to CISA, and contact central@cisa.dhs.gov to coordinate finding a qualified service provider capable of conducting forensics.

All other provisions specified in ED 21-01 remain in effect.

Federal Information Systems Hosted in Third-Party Environments (such as Cloud)

CISA is working closely with FedRAMP to coordinate the response to ED 21-01 with FedRAMP Authorized cloud service providers (CSPs). FedRAMP Authorized CSPs have been informed to coordinate with their agency customers.

  1. If FedRAMP Authorized CSPs are affected, their agency customers must report incidents to CISA in accordance with ED 21-01. Agencies hosting information in any third-party environment (FedRAMP Authorized or otherwise) must identify and contact their third-party service providers directly for status pertaining to, and to ensure compliance with, ED 21-01.
  2. Agencies are also instructed to supplement their reporting under ED 21-01 to incorporate relevant information from third-party service providers (to the extent that agencies have not already included this information), including to report any incident through CISA. In your incident reporting, please identify what data was exposed to the third-party service provider.

Conditions for Reconnecting Unaffected Versions

At this time, CISA is still assessing whether it is appropriate to relax ED 21-01’s requirement that agencies not install patches for their SolarWinds Orion software. Some older versions of SolarWinds Orion have been identified as not affected by the malicious backdoor. However, operating such older versions carries significant risk, because (1) like other types of older software, older versions of SolarWinds Orion contain known vulnerabilities; (2) the adversary that inserted the SolarWinds Orion backdoor is likely to be intimately familiar with SolarWinds Orion code, including known or unknown vulnerabilities that may exist separate and apart from the backdoor; and (3) this adversary has demonstrated the capability and willingness to exploit SolarWinds Orion to compromise U.S. government agencies, critical infrastructure entities, and private organizations.

Agencies are permitted to power back up and reintroduce into an agency production environment SolarWinds Orion instances that were disconnected pursuant to ED 21-01 only if each of the following conditions are met:

  1. The instance currently uses an unaffected version of the SolarWinds Orion, which are listed below.

a. Orion Platform 2019.4 2019.4.5200.8890

b. Orion Platform 2019.4 HF1 2019.4.5200.8950

c. Orion Platform 2019.4 HF2 2019.4.5200.8996

d. Orion Platform 2019.4 HF3 2019.4.5200.9001

e. Orion Platform 2019.4 HF4 2019.4.5200.9045

  1. The instance did not previously use an affected version (i.e., the instance was never rolled back from an affected version) and the instance is not restored from an affected version.
  2. The agency first (1) hunts for threat actors in their environment using all IOCs and indicators of threat actor activity published about this threat activity in ED 21-01, Activity Alert AA20-352A, and any additional related guidance related to this activity published by CISA or provided by the information security community prior to the instance being reintroduced to the environment, and (2) finds no evidence of such threat actor activity.
  3. The agency conducts a risk assessment to assess the impact of reintroducing the Orion Platform into agency production environments and accepts residual risk associated with running this unpatched software containing known vulnerabilities until such time as CISA permits agencies to patch these products.
  4. Block all incoming and outgoing (any:any) Internet traffic to and from hosts running SolarWinds Orion products (as required by ED 21-01).
  5. Follow the SolarWinds hardening guidelines provided by the vendor, which can be found at: https://documentation.solarwinds.com/en/Success_Center/orionplatform/content/core-secure-configuration.htm


a. Agencies shall not configure the SolarWinds software to implement SAML-based authentication that relies on Microsoft’s Active Directory Federated Services. This configuration is currently being exploited by the threat actor associated with this activity.

b. Agencies shall not follow the hardening guideline’s requirement to ensure their SolarWinds instance is patched to the latest version, pending further direction from CISA to do so.

  1. Ensure that the SolarWinds logs are being sent to the agency SOC for action.

Other Versions

Agencies continuing to run instances of SolarWinds Orion with other versions must comply with steps 5-7 listed for unaffected versions.

Agencies may apply updates to host operating system running SolarWinds Orion products in accordance with their respective vulnerability and patch management policies and programs.

All other provisions specified in ED 21-01 remain in effect.