: Their analysis of the NOBELIUM toolset explains the handoff between different malware stages (e.g., from SUNBURST to Teardrop/PoolBoy).

The file is a widely documented example of a malware sample , specifically associated with a variant of the PoolBoy backdoor . This malware has been linked to the advanced persistent threat (APT) group UNC2452 (also known as DarkHALO or NOBELIUM), the actors behind the SolarWinds supply chain attack . Technical Overview

: Their report on the UNC2452/SolarWinds campaign provides the most granular details on how PoolBoy functions within the broader attack lifecycle.