Only 1 / 67 antivirus engines list SUNBURST backdoor as malicious - SolarWinds.Orion.Core.BusinessLayer.dll https://www.virustotal.com/gui/file/32519b85c0b422e4656de6e6c41878e95fd95026267daab4215ee59c107d6c77/detection #SUNBURST #UNC2452
SolarWinds' digital certificate hasn't been revoked yet.
The full compromised package is still being hosted online as well 😓 hxxps://downloads.solarwinds[.]com/solarwinds/CatalogResources/Core/2019.4/2019.4.5220.20574/SolarWinds-Core-v2019.4.5220-Hotfix5.msp
Job class within the backdoored #Sunburst DLL is pretty straight forward and aligns with @FireEye's analysis. CollectSystemDescription:
DeleteFile
DeleteRegistryValue
FileExists
#UNC2452 prefers MD5 for their file hashing routine
#UNC2452's DirList is savvy enough to always expand environment variables. Doesn't appear to have any recursion or depth arguments for DirWalk'ing.
Use of token manipulation was underwhelming. Sets process privilege to SeTakeOwnershipPrivilege, SeRestorePrivilege, and SeShutdownPrivilege.
Domain1 = http://avsvmcloud.com 
(just like the report said). Thus far all analysis has held up (no real surprise there).
One of the anomalous #SUNBURST DLLs from October 2019 that Microsoft highlighted can be found in the SolarWinds Coreinstall.msi for 2019.4.5220.20161 - hxxps://downloads.solarwinds[.]com/solarwinds/CatalogResources/Core/2019.4/2019.4.5220.20161/CoreInstaller.msi
Malicious #SUNBURST DLL CE77D116A074DAB7A22A0FD4F2C1AB475F16EEC42E1DED3C0B0AA8211FE858D6 from May 2020 can be found in CoreInstaller.msi for 2020.2.5320.27438 -hxxps://downloads.solarwinds[.]com/solarwinds/CatalogResources/Core/2020.2/2020.2.5320.27438/CoreInstaller.msi
Malicious #SUNBUST DLL 019085A76BA7126FFF22770D71BD901C325FC68AC55AA743327984E89F4B0134 from April 2020 can be found in CoreInstaller.msi for 2020.2.5220.27327 - hxxps://downloads.solarwinds[.]com/solarwinds/CatalogResources/Core/2020.2/2020.2.5220.27327/CoreInstaller.msi
For those asking about the "obfuscation" of strings, here's a quick and dirty way to convert their base64 into a cleartext result. https://gist.github.com/KyleHanslovan/8e81c2faba42bc8108cdd996ac8d860a
This gist emulates the ZipHelper class method Unzip() which base64 decodes then calls Decompress().
https://gist.github.com/KyleHanslovan/8e81c2faba42bc8108cdd996ac8d860a
You can follow @KyleHanslovan.
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