Windows Process Creation: whoami.exe Executed With /all for Full Identity Enumeration

Detects Windows executions of whoami.exe using the /all flag to enumerate full identity details.

FreeReviewedSigma · Medium · v1

Product: windows
Category: process_creation
Author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published: 2023-12-04
Updated: 2026-07-30

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 flags execution of whoami.exe when invoked with the /all argument, which returns comprehensive local user and system identity information. Attackers commonly use this output for discovery and to tailor follow-on actions based on the compromised environment. The detection relies on Windows process creation telemetry, specifically the executable identity (path or OriginalFileName) and the command line containing the /all flag.

Reporting behind it

Related detections9 linkedT1033 — drag to rearrange

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Suspicious Reconnaissance Spawned by Injected SearchProtocolHost via process_creation

Linux Process Execution of esxcli Network Commands for ESXi Network Discovery

Linux Process Execution of esxcli VM Listing Commands

Linux ESXi esxcli VSAN Information Discovery via esxcli Command

Linux Process Creation: ESXi esxcli system discovery via system namespace

Linux ESXi esxcli Storage Information Discovery via esxcli storage commands

Windows whoami.exe Group Membership Reconnaissance via /groups Flag

Windows Process Creation: whoami.exe Executed With /all for Full Identity Enumeration

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-creation-whoami-exe-executed-with-all-for-full-identity-enumerat-c248c896

title: "Windows Process Creation: whoami.exe Executed With /all for Full Identity Enumeration"
id: 115d3ec4-e77c-4a56-ba40-8f963105d61f
status: test
description: This rule flags execution of whoami.exe when invoked with the /all argument, which returns comprehensive local user and system identity information. Attackers commonly use this output for discovery and to tailor follow-on actions based on the compromised environment. The detection relies on Windows process creation telemetry, specifically the executable identity (path or OriginalFileName) and the command line containing the /all flag.
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
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_whoami_all_execution.yml
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-12-04
modified: 2024-03-05
tags:
  - attack.discovery
  - attack.t1033
  - car.2016-03-001
logsource:
  category: process_creation
  product: windows
detection:
  selection_main_img:
    - Image|endswith: \whoami.exe
    - OriginalFileName: whoami.exe
  selection_main_cli:
    CommandLine|contains|windash: " -all"
  condition: all of selection_main_*
falsepositives:
  - Unknown
level: medium
license: DRL-1.1
related:
  - id: c248c896-e412-4279-8c15-1c558067b6fa
    type: derived

Convert

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