Whoami.EXE Execution Anomaly

Title: Whoami.EXE Execution Anomaly
Status: test
Description:Detects the execution of whoami.exe with suspicious parent processes.
References:
  -https://brica.de/alerts/alert/public/1247926/agent-tesla-keylogger-delivered-inside-a-power-iso-daa-archive/
  -https://app.any.run/tasks/7eaba74e-c1ea-400f-9c17-5e30eee89906/
  -https://www.youtube.com/watch?v=DsJ9ByX84o4&t=6s
Author: Florian Roth (Nextron Systems)
Date: 2021-08-12
modified:2025-03-06
Tags:

• -'attack.discovery'
• -'attack.t1033'
• -'car.2016-03-001'

Logsource:

• category: process_creation
• product: windows

Detection:
  selection:
Image|endswith:'\whoami.exe' OriginalFileName:'whoami.exe'   filter_main_known_parents:
    ParentImage|endswith:
      -'\cmd.exe'
      -'\powershell_ise.exe'
      -'\powershell.exe'
      -'\pwsh.exe'

  filter_optional_ms_monitoring_agent:
    ParentImage|endswith: ':\Program Files\Microsoft Monitoring Agent\Agent\MonitoringHost.exe'
  filter_main_parent_null:
    ParentImage: 'None'
  filter_main_parent_empty:
    ParentImage:
      -''
      -'-'

  condition:selection and not 1 of filter_main_* and not 1 of filter_optional_*
Falsepositives:
  -Admin activity
  -Scripts and administrative tools used in the monitored environment
  -Monitoring activity
Level: medium