title: CMSTP UAC Bypass via COM Object Access
id: 4b60e6f2-bf39-47b4-b4ea-398e33cfe253
status: stable
description: Detects UAC Bypass Attempt Using Microsoft Connection Manager Profile Installer Autoelevate-capable COM Objects
tags:
    - attack.execution
    - attack.defense_evasion
    - attack.privilege_escalation
    - attack.t1548.002
    - attack.t1088  # an old one
    - attack.t1218.003
    - attack.t1191  # an old one
    - attack.g0069
    - car.2019-04-001
author: Nik Seetharaman
modified: 2019/07/31
date: 2019/01/16
references:
    - https://web.archive.org/web/20190720093911/http://www.endurant.io/cmstp/detecting-cmstp-enabled-code-execution-and-uac-bypass-with-sysmon/
    - https://twitter.com/hFireF0X/status/897640081053364225
logsource:
    category: process_creation
    product: windows
detection:
    selection1:
        ParentCommandLine|contains: '\DllHost.exe '
    selection2:
        ParentCommandLine|endswith:
            - '{3E5FC7F9-9A51-4367-9063-A120244FBEC7}'
            - '{3E000D72-A845-4CD9-BD83-80C07C3B881F}'
    condition: selection1 and selection2
fields:
    - CommandLine
    - ParentCommandLine
    - Hashes
falsepositives:
    - Legitimate CMSTP use (unlikely in modern enterprise environments)
level: high