Sigma rule: Suspicious PowerShell Get Current User

Rule

Title

Suspicious PowerShell Get Current User

Status

test

Level

low

Author

frack113

Date

2022-04-04

File

rules/windows/powershell/powershell_script/posh_ps_susp_get_current_user.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects the use of PowerShell to identify the current logged user.

Log source

product

windows

category

ps_script

definition

Requirements: Script Block Logging must be enabled

Detection

selection:
    ScriptBlockText|contains:
        - '[System.Environment]::UserName'
        - '$env:UserName'
        - '[System.Security.Principal.WindowsIdentity]::GetCurrent()'
condition: selection

False positives (as the rule lists them)

• Legitimate PowerShell scripts

Tags

• attack.discovery
• attack.t1033

MITRE ATT&CK ids this rule names

• T1033

References

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1033/T1033.md#atomic-test-4---user-discovery-with-env-vars-powershell-script
• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1033/T1033.md#atomic-test-5---getcurrent-user-with-powershell-script

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_susp_get_current_user.yml