Extent of the Supply Chain Attack on SolarWinds Orion Platform Software

Extent of the Supply Chain Attack on SolarWinds Orion Platform Software 

In the past few days, details about the supply chain attack on the SolarWinds Orion Platform software have slowly unfolded, highlighting the dangers of this type of cyberattack.

What Is a Supply Chain Attack?

Supply chain attack is a type of cyberattack in which attackers maliciously change the source code of a software with the goal of compromising the end users of the said software.

In a statement, SolarWinds said it was a victim of a supply chain attack in which a still unknown attacker inserted a malicious software (malware) dubbed as “Sunburst” within SolarWinds Orion Platform software. According to SolarWinds, versions 2019.4 HF 5, 2020.2 with no hotfix installed, and 2020.2 HF 1 of its Orion Platform software were compromised with the Sunburst malware.

Customers of SolarWinds that downloaded and installed the company’s Orion Platform software versions 2019.4 HF 5, 2020.2 with no hotfix installed, and 2020.2 HF 1 are at risk. If present and activated, the Sunburst malware, according to SolarWinds, “could potentially allow an attacker to compromise the server on which the Orion products run.”

The effects of a compromised server hosting the Sunburst malware is far and wide as SolarWinds Orion Platform software is specifically meant as a centralized monitoring and management software to keep track of all IT resources, including servers, workstations, mobile devices, and IoT devices.

Cybersecurity firm FireEye first discovered the Sunburst malware. The company is also responsible for naming this malware as “Sunburst.” Microsoft, meanwhile, refers to this malware as “Solorigate.” FireEye and Microsoft both admitted that they have been part of the victims of the supply chain attack on SolarWinds Orion Platform software.

Microsoft, in a statement, said: “Like other SolarWinds customers, we have been actively looking for indicators of this actor and can confirm that we detected malicious SolarWinds binaries in our environment, which we isolated and removed. We have not found evidence of access to production services or customer data. Our investigations, which are ongoing, have found absolutely no indications that our systems were used to attack others.”

In the case of FireEye, the attacker stole the company’s “Red Team assessment tools.” According to FireEye, the stolen Red Team assessment tools are used to test its customers’ security.

“These tools [Red Team assessment tools] mimic the behavior of many cyber threat actors and enable FireEye to provide essential diagnostic security services to our customers,” FireEye said. “None of the tools contain zero-day exploits.”

Sunburst/Solorigate Malware

According to FireEye, the Sunburst malware campaign may have started as early as Spring 2020 and is currently ongoing. In analyzing the Sunburst malware, FireEye said that after this malware is installed on the victim’s server, it stays dormant for up to two weeks. After this dormant period, the malware retrieves and executes commands, called “Jobs,” enabling transfer files, execute files, profile the system, reboot the machine, and disable system services.

FireEye added that the Sunburst malware hides its network traffic as the Orion Improvement Program (OIP) protocol “stores reconnaissance results within legitimate plugin configuration files,” allowing this malware to blend in with legitimate SolarWinds activity.

According to FireEye, victims of Sunburst malware include government, consulting, technology, telecom and extractive entities in North America, Europe, Asia and the Middle East. “We anticipate there are additional victims in other countries and verticals,” FireEye said.

In analyzing the Solorigate malware, Microsoft said that the malicious code inserted into SolarWinds Orion Platform software consists of nearly 4,000 lines of code. “The fact that the compromised file is digitally signed suggests the attackers were able to access the company’s software development or distribution pipeline,” said Microsoft 365 Defender Research Team and Microsoft Threat Intelligence Center in the blog post "Analyzing Solorigate, the compromised DLL file that started a sophisticated cyberattack, and how Microsoft Defender helps protect customers."

“Evidence suggests that as early as October 2019, these attackers have been testing their ability to insert code by adding empty classes,” Microsoft 365 Defender Research Team and Microsoft Threat Intelligence Center added. “Therefore, insertion of malicious code into the SolarWinds.Orion.Core.BusinessLayer.dll likely occurred at an early stage, before the final stages of the software build, which would include digitally signing the compiled code. As a result, the DLL containing the malicious code is also digitally signed, which enhances its ability to run privileged actions – and keep a low profile.”

Mitigating Measures Against Supply Chain Attack

In the case of the SolarWinds Orion Platform software supply chain attack, it’s important to apply the update released by SolarWinds. The company offers more details on how to apply the update here.

In case the Sunburst/Solorigate malware is suspected to be inside your organization’s network, it’s important to isolate and block internet access to IT infrastructure where SolarWinds software was installed for further review and investigation.

If isolation isn’t possible, the following mitigating measures should be taken:

• Block connectivity to endpoints from SolarWinds servers, especially those that contained critical data or those considered as crown jewel assets of your organization.
• Restrict the scope of accounts that have local administrator privileged on SolarWinds servers.
• Block internet access from servers or other endpoints with SolarWinds software.
• Change login details for accounts that have access to SolarWinds servers or infrastructure.
• Review network device configurations for unauthorized modifications.