Detection rules › Sigma

Vulnerable Driver Blocklist Registry Tampering Via CommandLine

Status
experimental
Severity
high
Log source
product windows, category process_creation
Author
Swachchhanda Shrawan Poudel (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects tampering of the Vulnerable Driver Blocklist registry via command line tools such as PowerShell or REG.EXE. The Vulnerable Driver Blocklist is a security feature that helps prevent the loading of known vulnerable drivers. Disabling this feature may indicate an attempt to bypass security controls, often targeted by threat actors to facilitate the installation of malicious or vulnerable drivers, particularly in scenarios involving Endpoint Detection and Response

MITRE ATT&CK coverage

TacticTechniques
Defense ImpairmentT1685 Disable or Modify Tools

Event coverage

ProviderEventTitle
SysmonEvent ID 1Process creation

Rule body yaml

title: Vulnerable Driver Blocklist Registry Tampering Via CommandLine
id: 22154f0e-5132-4a54-aa78-cc62f6def531
related:
    - id: d526c60a-e236-4011-b165-831ffa52ab70
      type: similar
status: experimental
description: |
    Detects tampering of the Vulnerable Driver Blocklist registry via command line tools such as PowerShell or REG.EXE.
    The Vulnerable Driver Blocklist is a security feature that helps prevent the loading of known vulnerable drivers.
    Disabling this feature may indicate an attempt to bypass security controls, often targeted by threat actors
    to facilitate the installation of malicious or vulnerable drivers, particularly in scenarios involving Endpoint Detection and Response
references:
    - https://www.sophos.com/en-us/blog/sharpening-the-knife-gold-blades-strategic-evolution
    - https://learn.microsoft.com/en-us/windows/security/application-security/application-control/app-control-for-business/design/microsoft-recommended-driver-block-rules
author: Swachchhanda Shrawan Poudel (Nextron Systems)
date: 2026-01-26
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    category: process_creation
    product: windows
detection:
    selection_img:
        - Image|endswith:
              - '\powershell.exe'
              - '\pwsh.exe'
              - '\reg.exe'
        - OriginalFileName:
              - 'PowerShell.EXE'
              - 'pwsh.dll'
              - 'reg.exe'
    selection_cli_1:
        CommandLine|contains:
            - 'add '
            - 'New-ItemProperty '
            - 'Set-ItemProperty '
            - 'si '  # SetItem Alias
    selection_cli_2:
        CommandLine|contains|all:
            - '\Control\CI\Config'
            - 'VulnerableDriverBlocklistEnable'
    condition: all of selection_*
falsepositives:
    - It is very unlikely for legitimate activities to disable the Vulnerable Driver Blocklist via command line tools; thus it is recommended to investigate promptly.
level: high
regression_tests_path: regression_data/rules/windows/process_creation/proc_creation_win_vulnerable_driver_blocklist_registry_tampering/info.yml

Stages and Predicates

Stage 0: condition

all of selection_*

Stage 1: selection_img

selection_img:
    - Image|endswith:
          - '\powershell.exe'
          - '\pwsh.exe'
          - '\reg.exe'
    - OriginalFileName:
          - 'PowerShell.EXE'
          - 'pwsh.dll'
          - 'reg.exe'

Stage 2: selection_cli_1

selection_cli_1:
    CommandLine|contains:
        - 'add '
        - 'New-ItemProperty '
        - 'Set-ItemProperty '
        - 'si '

Stage 3: selection_cli_2

selection_cli_2:
    CommandLine|contains|all:
        - '\Control\CI\Config'
        - 'VulnerableDriverBlocklistEnable'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
CommandLinematch
  • New-ItemProperty corpus 3 (sigma 3)
  • Set-ItemProperty corpus 3 (sigma 3)
  • VulnerableDriverBlocklistEnable
  • \Control\CI\Config
  • add corpus 12 (sigma 12)
  • si corpus 5 (sigma 5)
Imageends_with
  • \powershell.exe corpus 182 (sigma 182)
  • \pwsh.exe corpus 168 (sigma 168)
  • \reg.exe corpus 58 (sigma 58)
OriginalFileNameeq
  • PowerShell.EXE corpus 120 (sigma 84, splunk 30, elastic 6)
  • pwsh.dll corpus 112 (sigma 79, splunk 30, elastic 3)
  • reg.exe corpus 42 (sigma 32, splunk 8, elastic 2)