sigmahighHunting

Potential PowerShell Execution Via DLL

Detects potential PowerShell execution from a DLL instead of the usual PowerShell process as seen used in PowerShdll. This detection assumes that PowerShell commands are passed via the CommandLine.

MITRE ATT&CK

T1218.011

defense-evasion

Detection Query

selection_img:
  - Image|endswith:
      - \InstallUtil.exe
      - \RegAsm.exe
      - \RegSvcs.exe
      - \regsvr32.exe
      - \rundll32.exe
  - OriginalFileName:
      - InstallUtil.exe
      - RegAsm.exe
      - RegSvcs.exe
      - REGSVR32.EXE
      - RUNDLL32.EXE
selection_cli:
  CommandLine|contains:
    - Default.GetString
    - DownloadString
    - FromBase64String
    - "ICM "
    - "IEX "
    - Invoke-Command
    - Invoke-Expression
condition: all of selection_*

Author

Markus Neis, Nasreddine Bencherchali (Nextron Systems)

Created

2018-08-25

Data Sources

windowsProcess Creation Events

Platforms

windows

References

https://github.com/p3nt4/PowerShdll/blob/62cfa172fb4e1f7f4ac00ca942685baeb88ff356/README.md

Tags

attack.defense-evasionattack.t1218.011

Raw Content

title: Potential PowerShell Execution Via DLL
id: 6812a10b-60ea-420c-832f-dfcc33b646ba
status: test
description: |
    Detects potential PowerShell execution from a DLL instead of the usual PowerShell process as seen used in PowerShdll.
    This detection assumes that PowerShell commands are passed via the CommandLine.
references:
    - https://github.com/p3nt4/PowerShdll/blob/62cfa172fb4e1f7f4ac00ca942685baeb88ff356/README.md
author: Markus Neis, Nasreddine Bencherchali (Nextron Systems)
date: 2018-08-25
modified: 2024-03-07
tags:
    - attack.defense-evasion
    - attack.t1218.011
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\InstallUtil.exe'
              - '\RegAsm.exe'
              - '\RegSvcs.exe'
              - '\regsvr32.exe'
              - '\rundll32.exe'
        - OriginalFileName:
              - 'InstallUtil.exe'
              - 'RegAsm.exe'
              - 'RegSvcs.exe'
              - 'REGSVR32.EXE'
              - 'RUNDLL32.EXE'
    selection_cli:
        CommandLine|contains:
            - 'Default.GetString'
            - 'DownloadString'
            - 'FromBase64String'
            - 'ICM '
            - 'IEX '
            - 'Invoke-Command'
            - 'Invoke-Expression'
    condition: all of selection_*
falsepositives:
    - Unknown
level: high