Sigma rule: Potentially Suspicious Child Process Of Regsvr32

Rule

Title

Potentially Suspicious Child Process Of Regsvr32

Status

test

Level

high

Author

elhoim, Florian Roth (Nextron Systems), Nasreddine Bencherchali (Nextron Systems)

Date

2022-05-05

Modified

2023-05-26

File

rules/windows/process_creation/proc_creation_win_regsvr32_susp_child_process.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects potentially suspicious child processes of "regsvr32.exe".

Log source

product

windows

category

process_creation

Detection

selection:
    ParentImage|endswith: '\regsvr32.exe'
    Image|endswith:
        - '\calc.exe'
        - '\cscript.exe'
        - '\explorer.exe'
        - '\mshta.exe'
        - '\net.exe'
        - '\net1.exe'
        - '\nltest.exe'
        - '\notepad.exe'
        - '\powershell.exe'
        - '\pwsh.exe'
        - '\reg.exe'
        - '\schtasks.exe'
        - '\werfault.exe'
        - '\wscript.exe'
filter_main_werfault:
    Image|endswith: '\werfault.exe'
    CommandLine|contains: ' -u -p '
condition: selection and not 1 of filter_main_*

False positives (as the rule lists them)

• Unlikely, but can rarely occur. Apply additional filters accordingly.

Tags

• attack.stealth
• attack.t1218.010

MITRE ATT&CK ids this rule names

• T1218.010

Related rules

• 8e2b24c9-4add-46a0-b4bb-0057b4e6187d (obsolete)

References

• https://redcanary.com/blog/intelligence-insights-april-2022/
• https://www.echotrail.io/insights/search/regsvr32.exe
• https://www.ired.team/offensive-security/code-execution/t1117-regsvr32-aka-squiblydoo

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_regsvr32_susp_child_process.yml