Detection rules › Sigma
Potentially Suspicious Execution From Parent Process In Public Folder
Detects a potentially suspicious execution of a parent process located in the "\Users\Public" folder executing a child process containing references to shell or scripting binaries and commandlines.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Execution | |
| Stealth |
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: Potentially Suspicious Execution From Parent Process In Public Folder
id: 69bd9b97-2be2-41b6-9816-fb08757a4d1a
status: test
description: |
Detects a potentially suspicious execution of a parent process located in the "\Users\Public" folder executing a child process containing references to shell or scripting binaries and commandlines.
references:
- https://redcanary.com/blog/blackbyte-ransomware/
author: Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)
date: 2022-02-25
modified: 2024-07-12
tags:
- attack.execution
- attack.stealth
- attack.t1564
- attack.t1059
logsource:
category: process_creation
product: windows
detection:
selection_parent:
ParentImage|contains: ':\Users\Public\'
selection_child:
- Image|endswith:
- '\bitsadmin.exe'
- '\certutil.exe'
- '\cmd.exe'
- '\cscript.exe'
- '\mshta.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\wscript.exe'
- CommandLine|contains:
- 'bitsadmin'
- 'certutil'
- 'cscript'
- 'mshta'
- 'powershell'
- 'regsvr32'
- 'rundll32'
- 'wscript'
condition: all of selection_*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
all of selection_*Stage 1: selection_parent
selection_parent:
ParentImage|contains: ':\Users\Public\'
Stage 2: selection_child
selection_child:
- Image|endswith:
- '\bitsadmin.exe'
- '\certutil.exe'
- '\cmd.exe'
- '\cscript.exe'
- '\mshta.exe'
- '\powershell.exe'
- '\pwsh.exe'
- '\regsvr32.exe'
- '\rundll32.exe'
- '\wscript.exe'
- CommandLine|contains:
- 'bitsadmin'
- 'certutil'
- 'cscript'
- 'mshta'
- 'powershell'
- 'regsvr32'
- 'rundll32'
- 'wscript'
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 |
ParentImage | match |
| field:"ParentImage" kind:match value:":\Users\Public\" |