SigmaHQ/rules/windows/process_creation/win_shell_spawn_susp_program.yml

title: Windows Shell Spawning Suspicious Program
id: 3a6586ad-127a-4d3b-a677-1e6eacdf8fde
status: experimental
description: Detects a suspicious child process of a Windows shell
references:
    - https://mgreen27.github.io/posts/2018/04/02/DownloadCradle.html
author: Florian Roth
date: 2018/04/06
modified: 2020/09/06
tags:
    - attack.execution
    - attack.defense_evasion
    - attack.t1064 # an old one
    - attack.t1059.005
    - attack.t1059.001
    - attack.t1218    
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        ParentImage|endswith:
            - '\mshta.exe'
            - '\powershell.exe'
            # - '*\cmd.exe'  # too many false positives
            - '\rundll32.exe'
            - '\cscript.exe'
            - '\wscript.exe'
            - '\wmiprvse.exe'
        Image|endswith:
            - '\schtasks.exe'
            - '\nslookup.exe'
            - '\certutil.exe'
            - '\bitsadmin.exe'
            - '\mshta.exe'
    falsepositives:
        CurrentDirectory|contains: '\ccmcache\'
    condition: selection and not falsepositives
fields:
    - CommandLine
    - ParentCommandLine
falsepositives:
    - Administrative scripts
    - Microsoft SCCM
level: high