sigmamediumHunting

Potentially Suspicious Child Process Of VsCode

Detects uncommon or suspicious child processes spawning from a VsCode "code.exe" process. This could indicate an attempt of persistence via VsCode tasks or terminal profiles.

MITRE ATT&CK

T1218 T1202

executiondefense-evasion

Detection Query

selection_parent:
  ParentImage|endswith: \code.exe
selection_children_images:
  Image|endswith:
    - \calc.exe
    - \regsvr32.exe
    - \rundll32.exe
    - \cscript.exe
    - \wscript.exe
selection_children_cli:
  Image|endswith:
    - \powershell.exe
    - \pwsh.exe
    - \cmd.exe
  CommandLine|contains:
    - Invoke-Expressions
    - IEX
    - Invoke-Command
    - ICM
    - DownloadString
    - rundll32
    - regsvr32
    - wscript
    - cscript
selection_children_paths:
  Image|contains:
    - :\Users\Public\
    - :\Windows\Temp\
    - :\Temp\
condition: selection_parent and 1 of selection_children_*

Author

Nasreddine Bencherchali (Nextron Systems)

Created

2023-01-26

Data Sources

windowsProcess Creation Events

Platforms

windows

References

Tags

attack.executionattack.defense-evasionattack.t1218attack.t1202

Raw Content

title: Potentially Suspicious Child Process Of VsCode
id: 5a3164f2-b373-4152-93cf-090b13c12d27
status: test
description: Detects uncommon or suspicious child processes spawning from a VsCode "code.exe" process. This could indicate an attempt of persistence via VsCode tasks or terminal profiles.
references:
    - https://twitter.com/nas_bench/status/1618021838407495681
    - https://twitter.com/nas_bench/status/1618021415852335105
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-01-26
modified: 2023-10-25
tags:
    - attack.execution
    - attack.defense-evasion
    - attack.t1218
    - attack.t1202
logsource:
    category: process_creation
    product: windows
detection:
    selection_parent:
        ParentImage|endswith: '\code.exe'
    selection_children_images:
        Image|endswith:
            - '\calc.exe'
            - '\regsvr32.exe'
            - '\rundll32.exe'
            - '\cscript.exe'
            - '\wscript.exe'
    selection_children_cli:
        Image|endswith:
            - '\powershell.exe'
            - '\pwsh.exe'
            - '\cmd.exe'
        CommandLine|contains:
            - 'Invoke-Expressions'
            - 'IEX'
            - 'Invoke-Command'
            - 'ICM'
            - 'DownloadString'
            - 'rundll32'
            - 'regsvr32'
            - 'wscript'
            - 'cscript'
    selection_children_paths:
        Image|contains:
            # Add more suspicious locations
            - ':\Users\Public\'
            - ':\Windows\Temp\'
            - ':\Temp\'
    condition: selection_parent and 1 of selection_children_*
falsepositives:
    - In development environment where VsCode is used heavily. False positives may occur when developers use task to compile or execute different types of code. Remove or add processes accordingly
level: medium