Screening Serpens MiniUpdate RAT Activity Detection
Detects indicators associated with the MiniUpdate RAT deployed by the threat group Screening Serpens. This rule identifies network connections to known C2 domains, the creation of a persistence scheduled task named 'WindowsSecurityUpdate', and the dropping of specific RAT module DLLs ('UpdateChecker.dll', 'InitInstall.dll', 'Updater.dll') in common user-writable directories. The file event detection is tuned to require multiple generic DLLs or the presence of 'InitInstall.dll' to reduce false positives.
Microsoft Sentinel (KQL)

