Possible DLL Sideloading Of MsCorSvc.DLL (via image_load)

title: Possible DLL Sideloading Of MsCorSvc.DLL (via image_load)
id: fc886fe5-7a35-5ab3-969c-53f65efeaafa
status: stable
description: This rule detects potential DLL sideloading of "mscorsvc.dll".
references:
    - https://attack.mitre.org/techniques/T1574/001/
    - https://hijacklibs.net/entries/microsoft/built-in/mscorsvc.html
author: Huntrule Team
date: 2026-04-13
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.execution
    - attack.stealth
    - attack.t1574.001
logsource:
    product: windows
    category: image_load
detection:
    selection:
        ImageLoaded|endswith: '\mscorsvc.dll'
    filter_main_generic:
        ImageLoaded|startswith:
            - 'C:\Windows\Microsoft.NET\Framework\'
            - 'C:\Windows\Microsoft.NET\Framework64\'
            - 'C:\Windows\Microsoft.NET\FrameworkArm\'
            - 'C:\Windows\Microsoft.NET\FrameworkArm64\'
            - 'C:\Windows\WinSxS\'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium