Sigma rule: Potentially Suspicious Mofcomp Execution

Rule

Title

Potentially Suspicious Mofcomp Execution

Status

test

Level

high

Author

Nasreddine Bencherchali (Nextron Systems)

Date

2022-07-12

Modified

2026-08-06

File

rules/windows/process_creation/proc_creation_win_mofcomp_execution.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects execution of the "mofcomp" utility as a child of a suspicious shell or script running utility or by having a suspicious path in the commandline.
The "mofcomp" utility parses a file containing MOF statements and adds the classes and class instances defined in the file to the WMI repository.
Attackers abuse this utility to install malicious MOF scripts

Log source

product

windows

category

process_creation

Detection

selection_img:
    - Image|endswith: '\mofcomp.exe'
    - OriginalFileName: 'mofcomp.exe'
selection_case:
    - ParentImage|endswith:
          - '\cmd.exe'
          - '\powershell.exe'
          - '\pwsh.exe'
          - '\wsl.exe'
          - '\wscript.exe'
          - '\cscript.exe'
    - CommandLine|contains:
          - '\AppData\Local\Temp'
          - '\Contacts\'
          - '\Favorites\'
          - '\Favourites\'
          - '\Music\'
          - '\Pictures\'
          - '\Users\Public\'
          - '\Videos\'
          - '\WINDOWS\Temp\'
          - '%appdata%'
          - '%temp%'
          - '%tmp%'
filter_main_wmiprvse:
    ParentImage: 'C:\Windows\System32\wbem\WmiPrvSE.exe'
    CommandLine|contains: 'C:\Windows\TEMP\'
    CommandLine|endswith: '.mof'
filter_main_installutil:
    ParentCommandLine|endswith: '\InstallUtil.exe /Uninstall C:\Windows\CCM\Microsoft.ConfigurationManager.SVProvider.dll'
    ParentImage|endswith: '\InstallUtil.exe'
    CommandLine|contains|all:
        - 'C:\Windows\TEMP'
        - '.tmp'
filter_optional_null_parent:
    ParentCommandLine: null
condition: all of selection_* and not 1 of filter_main_* and not 1 of filter_optional_*

False positives (as the rule lists them)

• Unknown

Tags

• attack.stealth
• attack.t1218

MITRE ATT&CK ids this rule names

• T1218

References

• https://thedfirreport.com/2022/07/11/select-xmrig-from-sqlserver/
• https://github.com/The-DFIR-Report/Sigma-Rules/blob/75260568a7ffe61b2458ca05f6f25914efb44337/win_mofcomp_execution.yml
• https://learn.microsoft.com/en-us/windows/win32/wmisdk/mofcomp

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_mofcomp_execution.yml