sigmahighTTP

CMSTP App Paths Registry Key Modification

Detects modifications to the CMSTP App Paths registry key. This may indicate abuse of Microsoft Connection Manager Profile Installer (CMSTP) for arbitrary code execution or UAC bypass.

MITRE ATT&CK

T1218.003 G0069

execution

Detection Query

selection:
  TargetObject|contains: SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\cmmgr32.exe\
filter_main_cmcfg32:
  TargetObject|endswith: SOFTWARE\Microsoft\Windows\CurrentVersion\App
    Paths\cmmgr32.exe\CmstpExtensionDll
  Details:
    - C:\Windows\System32\cmcfg32.dll
    - C:\Windows\SysWOW64\cmcfg32.dll
filter_main_empty:
  Details: (Empty)
condition: selection and not 1 of filter_main_*

Author

Nik Seetharaman

Created

2018-07-16

Data Sources

windowsRegistry Events

Platforms

windows

References

Tags

attack.executionattack.stealthattack.t1218.003attack.g0069car.2019-04-001

Raw Content

title: CMSTP App Paths Registry Key Modification
id: b6d235fc-1d38-4b12-adbe-325f06728f37
status: stable
description: |
    Detects modifications to the CMSTP App Paths registry key. This may indicate abuse of
    Microsoft Connection Manager Profile Installer (CMSTP) for arbitrary code execution or UAC bypass.
references:
    - https://lolbas-project.github.io/lolbas/Binaries/Cmstp/
    - https://web.archive.org/web/20190720093911/http://www.endurant.io/cmstp/detecting-cmstp-enabled-code-execution-and-uac-bypass-with-sysmon/
    - https://web.archive.org/web/20190722224110/https://oddvar.moe/2017/08/15/research-on-cmstp-exe/
author: Nik Seetharaman
date: 2018-07-16
modified: 2026-08-27
tags:
    - attack.execution
    - attack.stealth
    - attack.t1218.003
    - attack.g0069
    - car.2019-04-001
logsource:
    category: registry_event
    product: windows
detection:
    selection:
        TargetObject|contains: 'SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\cmmgr32.exe\'
    filter_main_cmcfg32:
        TargetObject|endswith: 'SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\cmmgr32.exe\CmstpExtensionDll'
        Details:
            - 'C:\Windows\System32\cmcfg32.dll'
            - 'C:\Windows\SysWOW64\cmcfg32.dll'
    filter_main_empty:
        Details: '(Empty)'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Legitimate CMSTP use (unlikely in modern enterprise environments)
level: high