General

  • Target
    https://github.com/theevilteam/Killer-Clown/releases
  • Sample260827-nb7h3atdqa

Malware Config

Targets

    • Modifies WinLogon for persistence

    • Deletes shadow copies

      Ransomware often targets backup files to inhibit system recovery.

    • Boot or Logon Autostart Execution: Active Setup

      Adversaries may achieve persistence by adding a Registry key to the Active Setup of the local machine.

    • Downloads MZ/PE file

    • Drops file in Drivers directory

    • Checks computer location settings

      Looks up country code configured in the registry, likely geofence.

    • Creates a file in the Startup directory

      A file was written to a Windows startup folder. Files in these directories are executed automatically when a user logs on or an application initializes.

    • Event Triggered Execution: Component Object Model Hijacking

      Adversaries may establish persistence by executing malicious content triggered by hijacked references to Component Object Model (COM) objects.

    • Executes dropped EXE

    • Loads dropped DLL

    • Modifies system executable filetype association

    • Adds Run key to start application

    • Enumerates connected drives

      Attempts to read the root path of hard drives other than the default C: drive.

    • Writes to the Master Boot Record (MBR)

      Bootkits write to the MBR to gain persistence at a level below the operating system.

    • Drops file in System32 directory

    • Executes a VBScript file via the Windows Script Host.

    • Sets desktop wallpaper using registry

    • Suspicious use of SetThreadContext

MITRE ATT&CK Enterprise v16

Tasks