huntrule

Windows whoami.exe Execution With /FO CSV or Output Redirection

Detects whoami.exe runs that request CSV output or indicate output redirection for saved results.

FreeReviewedSigma · Medium · v1
Product
windows
Category
process_creation
Author
Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-02-28
Updated
2026-07-30
AnalysisDetection

ATT&CK techniques

Discovery

  1. Recon

  2. Resource Dev

  3. Initial Access

  4. Execution

  5. Persistence

  6. Priv Esc

  7. Defense Evasion

  8. Cred Access

  9. Discovery

  10. Lateral Movement

  11. Collection

  12. C2

  13. Exfiltration

  14. Impact

What it detects

This rule flags process creation events where whoami.exe is executed with the /FO CSV option to format output as CSV, or where command-line patterns indicate exporting output to a file (including wildcard-style redirection such as whoami*>). Attackers commonly use whoami to enumerate the current user context before further actions, and exporting results can support staging or later collection. The detection relies on Windows process creation telemetry, specifically Image and OriginalFileName fields and CommandLine substring matches for the relevant flags and redirection patterns.

Reporting behind it

Related detections9 linkedT1033 — drag to rearrange
Suspicious Whoami Discovery Spawned by Windows Script Host via Process Creation (via process_creation)
Suspicious Localized Administrator Account and Group Enumeration After Citrix Bleed Exploitation
Malicious Recon Output Staged in Qlik Sense Fonts Directory by Cactus Ransomware
Suspicious Host Reconnaissance Command Chain via cmd
Malicious Child Process Spawned From n8n Node Process
Suspicious Credential Enumeration via cmdkey List
Suspicious IIS Worker Process Spawning Whoami Reconnaissance
Suspicious Whoami Execution With Output Redirected to a File (via process_creation)
Possible Logged-On Session Discovery via Quser or Qwinsta (via process_creation)
Windows whoami.exe Execution With /FO CSV or Output Redirection
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.