Antivirus Filter Driver Disallowed On Dev Drive - Registry

Hunt Hypothesis

Detects activity that indicates a user disabling the ability for Antivirus mini filter to inspect a “Dev Drive”.

Detection Rule

Sigma (Original)

title: Antivirus Filter Driver Disallowed On Dev Drive - Registry
id: 31e124fb-5dc4-42a0-83b3-44a69c77b271
status: test
description: |
    Detects activity that indicates a user disabling the ability for Antivirus mini filter to inspect a "Dev Drive".
references:
    - https://twitter.com/0gtweet/status/1720419490519752955
author: '@kostastsale, Nasreddine Bencherchali (Nextron Systems)'
date: 2023-11-05
modified: 2024-08-16
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|endswith: '\FilterManager\FltmgrDevDriveAllowAntivirusFilter'
        Details: 'DWORD (0x00000000)'
    condition: selection
falsepositives:
    - Unlikely
level: high

KQL (Azure Sentinel)

imRegistry
| where RegistryKey endswith "\\FilterManager\\FltmgrDevDriveAllowAntivirusFilter" and RegistryValueData =~ "DWORD (0x00000000)"

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where RegistryKey endswith "\\FilterManager\\FltmgrDevDriveAllowAntivirusFilter" and RegistryValueData =~ "DWORD (0x00000000)"

Required Data Sources

False Positive Guidance

• Unlikely

MITRE ATT&CK Context

• Technique: T1685 — T1685

References

• https://twitter.com/0gtweet/status/1720419490519752955
• SigmaHQ Rule