Windows Process Command Line Containing Whoami as First Parameter

ATT&CK techniques

Discovery

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
- T1033System Owner/User Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule identifies newly created Windows processes whose command line includes a pattern where '.exe whoami' appears, indicating that whoami is being passed as the first parameter to an executable. Such usage can be part of discovery or local reconnaissance by attempting to determine the current security context. It relies on process creation telemetry, specifically the full command line recorded at process start time.

Reporting behind it

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Windows Process Command Line Containing Whoami as First Parameter

Pivot detection · T1033 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

windows-process-command-line-containing-whoami-as-first-parameter-e9142d84

title: Windows Process Command Line Containing Whoami as First Parameter
id: 9bd5905d-6b73-4479-877a-e7e73d1ac3fa
status: test
description: This rule identifies newly created Windows processes whose command line includes a pattern where '.exe whoami' appears, indicating that whoami is being passed as the first parameter to an executable. Such usage can be part of discovery or local reconnaissance by attempting to determine the current security context. It relies on process creation telemetry, specifically the full command line recorded at process start time.
references:
  - https://twitter.com/blackarrowsec/status/1463805700602224645?s=12
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_susp_whoami_as_param.yml
author: Florian Roth (Nextron Systems), Huntrule Team
date: 2021-11-29
modified: 2022-12-25
tags:
  - attack.discovery
  - attack.t1033
  - car.2016-03-001
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    CommandLine|contains: .exe whoami
  condition: selection
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: e9142d84-fbe0-401d-ac50-3e519fb00c89
    type: derived

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