INSIGHTi

SolarWinds Attack—No Easy Fix
Updated December 18, 2020
On December 13, 2020, the cybersecurity firm FireEye published research that a malicious actor was
exploiting a supply chain vulnerability in SolarWinds products to hack into government and private sector
information technology (IT) networks. SolarWinds confirmed the security incident. The Cybersecurity
and Infrastructure Security Agency (CISA) issued an emergency directive requiring federal agencies to
remove certain SolarWinds products from agency networks.
Media initially reported that the U.S. Treasury and Commerce departments were susceptible to this attack;
subsequent reports added additional agencies. The list of compromised agencies and companies is
expected to expand.
As private sector and government researchers continue investigating this incident, the cybersecurity
community expects to learn more about the attack, the adversary, their targets, compromised data and
systems, and ways to recover from the incident. This Insight provides an overview of the incident, federal
response, and policy considerations.
The Attack
SolarWinds (Austin, TX) makes IT management products for business customers. These products allow
chief information officers (CIOs) to automate certain activities such as managing internet protocol (IP)
addresses, monitoring devices, and deploying updates.
A critical element to any software application or platform is the mechanism by which the vendor pushes
updates and patches to users. SolarWinds built functions into their products which push update files to
users (as is common practice).
A malicious actor discovered a way to compromise SolarWinds’ software update service for the Orion IT
management platform (a SolarWinds suite of products). The actor was able to compromise the update
channel used by Orion to distribute malware. When run, the code executed the Sunburst malware in the
SolarWinds IT management platform. Once executed, Sunburst would go dormant for a period of time (to
avoid detection) before fetching additional instructions from its command-and-control (C2) server. The
additional instructions allowed the actors to exfiltrate files, execute new commands, profile the system,
and manipulate the machine. The actors sought to hide their presence by manipulating files and disguising
their activity as normal network traffic. SolarWinds stated that of their 300,000-plus customers, roughly
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18,000 are susceptible to this attack. Known vulnerable versions of the platform were released in spring
2020 and were still vulnerable through mid-December 2020.
The disclosed attack is likely part of a larger campaign to which there is no easy fix. The Sunburst
malware allowed the malicious actors a foothold in their victims’ networks. From there, they could persist
in the network through the creation of additional credentials for other software platforms. So merely
remedying the vulnerable versions of SolarWinds’ products would be insufficient in eradicating the
unauthorized actors from a compromised network.
News media has attributed the attack to Russian intelligence services, but the Russian government has
denied involvement. The U.S. government recently attributed an unrelated exploit to VMWare products to
Russian state-sponsored actors.
FireEye previously disclosed a breach of its own hacking tools. FireEye’s breach did not contain
unknown exploits or techniques, so the SolarWinds vulnerability was not part of that breach.
Federal Actions
On December 13, 2020, CISA directed federal agencies to:
 disconnect and turn off certain SolarWinds products;
 block web traffic to any SolarWinds product; and
 hunt for adversaries that may be on the network (e.g., search for unauthorized credentials
and files) and remove them.
The CISA guidance encourages agencies with resident expertise to examine their SolarWinds products for
new accounts and network traffic for new domains. If an agency does not have this expertise, they may
request technical assistance from CISA. While these actions are compulsory for federal agencies, CISA
recommends nonfederal entities also undertake these actions.
CISA promised to continue working with federal and nonfederal partners to discover more information
about this exploitation and is to provide additional guidance and remediation actions when available.
The National Security Council has activated the National Cyber Incident Response Plan and has stood up
the Unified Coordination Group to streamline interagency collaboration.
The Defense Science Board warned of software update risks in 2017. The National Counterintelligence
and Security Center warned of software supply chain attacks in 2019.
Policy Considerations
Cybersecurity is not a static goal. Instead, it is a risk management process, which involves continual
work. The National Institute of Standards and Technology (NIST) Cybersecurity Framework categorizes
this process cycle as: (1) identify; (2) protect; (3) detect; (4) respond; and (5) recover. Much of the recent
cybersecurity policy work has been on the first three processes; the SolarWinds attack highlights the need
for the last two.
Given the nature of the SolarWinds attack, it is unlikely existing programs would have prevented this
incident. The Federal Information Security Modernization Act (FISMA) lays out roles for federal agency
cybersecurity, but ultimately places implementation responsibility with agency heads. Other recent
congressional activities, such as the SECURE IT Act and the IT MGT Act, address how agencies acquire
and deploy technology, but not how to manage it once it’s deployed. Agencies were recently directed to

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create vulnerability disclosure programs (VDPs), but government contractors were not required to have a
VDP.
Federal incident response capabilities may be over-taxed in the aftermath of this incident. The nature of
the attack granted the malicious actors great latitude to move about networks and carry out their
objectives. Agencies and private sector companies may lack the expertise or capacity to conduct hunt
activities on their own networks. Additionally, third party IT companies may not have the requisite
experience in:
 addressing advanced persistent threats on networks; and
 dealing with organizations of different sizes, complexity, and operations.
This may create a delay in remediating the consequences of the attack.
Addressing the response provides policymakers opportunities to dictate subsequent federal actions to
victim companies, agencies, and attributed perpetrators, and could inform how the private sector will
prioritize scarce resources. Lessons learned from this attack may also inform systemic changes to
cybersecurity policy. Office of Management and Budget (OMB) guidance requires agencies to plan for
incident response activities, but does not specifically address this particular risk.

Author Information

Chris Jaikaran

Analyst in Cybersecurity Policy




Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan shared staff
to congressional committees and Members of Congress. It operates solely at the behest of and under the direction of
Congress. Information in a CRS Report should not be relied upon for purposes other than public understanding of
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