SUNSPOT

S0562

Malware.View on attack.mitre.org

About this malware

SUNSPOT is an implant that injected the SUNBURST backdoor into the SolarWinds Orion software update framework. It was used by APT29 since at least February 2020.

Techniques used12

Procedure examples12

TechniqueProcedure example
T1027
Obfuscated Files or Information

SUNSPOT encrypted log entries it collected with the stream cipher RC4 using a hard-coded key. It also uses AES128-CBC encrypted blobs for SUNBURST source code and data extracted from the SolarWinds Orion <MsBuild.exe</code> process.

T1036.005
Match Legitimate Resource Name or Location

SUNSPOT was identified on disk with a filename of taskhostsvc.exe and it created an encrypted log file at C:\Windows\Temp\vmware-vmdmp.log.

T1057
Process Discovery

SUNSPOT monitored running processes for instances of MsBuild.exe by hashing the name of each running process and comparing it to the corresponding value 0x53D525. It also extracted command-line arguments and individual arguments from the running MsBuild.exe process to identify the directory path of the Orion software Visual Studio solution.

T1070.004
File Deletion

Following the successful injection of SUNBURST, SUNSPOT deleted a temporary file it created named InventoryManager.bk after restoring the original SolarWinds Orion source code to the software library.

T1083
File and Directory Discovery

SUNSPOT enumerated the Orion software Visual Studio solution directory path.

T1106
Native API

SUNSPOT used Windows API functions such as MoveFileEx and NtQueryInformationProcess as part of the SUNBURST injection process.

T1134
Access Token Manipulation

SUNSPOT modified its security token to grants itself debugging privileges by adding SeDebugPrivilege.

T1140
Deobfuscate/Decode Files or Information

SUNSPOT decrypts SUNBURST, which was stored in AES128-CBC encrypted blobs.

T1195.002
Compromise Software Supply Chain

SUNSPOT malware was designed and used to insert SUNBURST into software builds of the SolarWinds Orion IT management product.

T1480
Execution Guardrails

SUNSPOT only replaces SolarWinds Orion source code if the MD5 checksums of both the original source code file and backdoored replacement source code match hardcoded values.

T1480.002
Mutual Exclusion

SUNSPOT creates a mutex using the hard-coded value ` {12d61a41-4b74-7610-a4d8-3028d2f56395}` to ensure that only one instance of itself is running.

T1565.001
Stored Data Manipulation

SUNSPOT created a copy of the SolarWinds Orion software source file with a .bk extension to backup the original content, wrote SUNBURST using the same filename but with a .tmp extension, and then moved SUNBURST using MoveFileEx to the original filename with a .cs extension so it could be compiled within Orion software.

Groups that use it1

Campaigns1

References1

  1. CrowdStrike SUNSPOT Implant January 2021 Open source
    CrowdStrike Intelligence Team. (2021, January 11). SUNSPOT: An Implant in the Build Process. Retrieved January 11, 2021.

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