LOLBIN Execution From Abnormal Drive (via process_creation)

This rule detects LOLBINs running from an abnormal or uncommon drive such as a mounted ISO.

SigmamediumWindowsv1
sigma
title: LOLBIN Execution From Abnormal Drive (via process_creation)
id: b02a2d93-a870-5a0e-a572-0e112943c74f
status: stable
description: This rule detects LOLBINs running from an abnormal or uncommon drive such as a mounted ISO.
references:
    - https://thedfirreport.com/2021/12/13/diavol-ransomware/
    - https://www.scythe.io/library/threat-emulation-qakbot
    - https://sec-consult.com/blog/detail/bumblebee-hunting-with-a-velociraptor/
author: Huntrule Team
date: 2026-03-24
tags:
    - attack.stealth
    - attack.defense-evasion
    - attack.t1218
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        - Image|endswith:
              - '\calc.exe'
              - '\certutil.exe'
              - '\cmstp.exe'
              - '\cscript.exe'
              - '\installutil.exe'
              - '\mshta.exe'
              - '\regsvr32.exe'
              - '\rundll32.exe'
              - '\wscript.exe'
        - OriginalFileName:
              - 'CALC.EXE'
              - 'CertUtil.exe'
              - 'CMSTP.EXE'
              - 'cscript.exe'
              - 'installutil.exe'
              - 'MSHTA.EXE'
              - 'REGSVR32.EXE'
              - 'RUNDLL32.EXE'
              - 'wscript.exe'
    filter_main_currentdirectory:
        CurrentDirectory|contains: 'C:\'
    filter_main_empty:
        CurrentDirectory: ''
    filter_main_null:
        CurrentDirectory:
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: medium

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.