Scripted Diagnostics Turn Off Check Enabled - Registry

Hunt Hypothesis

Detects enabling TurnOffCheck which can be used to bypass defense of MSDT Follina vulnerability

Detection Rule

Sigma (Original)

title: Scripted Diagnostics Turn Off Check Enabled - Registry
id: 7d995e63-ec83-4aa3-89d5-8a17b5c87c86
status: test
description: Detects enabling TurnOffCheck which can be used to bypass defense of MSDT Follina vulnerability
references:
    - https://twitter.com/wdormann/status/1537075968568877057?s=20&t=0lr18OAnmAGoGpma6grLUw
author: 'Christopher Peacock @securepeacock, SCYTHE @scythe_io'
date: 2022-06-15
modified: 2023-08-17
tags:
    - attack.defense-impairment
    - attack.t1685
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|endswith: '\Policies\Microsoft\Windows\ScriptedDiagnostics\TurnOffCheck'
        Details: 'DWORD (0x00000001)'
    condition: selection
falsepositives:
    - Administrator actions
level: medium

KQL (Azure Sentinel)

imRegistry
| where RegistryKey endswith "\\Policies\\Microsoft\\Windows\\ScriptedDiagnostics\\TurnOffCheck" and RegistryValueData =~ "DWORD (0x00000001)"

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where RegistryKey endswith "\\Policies\\Microsoft\\Windows\\ScriptedDiagnostics\\TurnOffCheck" and RegistryValueData =~ "DWORD (0x00000001)"

Required Data Sources

False Positive Guidance

• Administrator actions

MITRE ATT&CK Context

• Technique: T1685 — T1685

References

• https://twitter.com/wdormann/status/1537075968568877057?s=20&t=0lr18OAnmAGoGpma6grLUw
• SigmaHQ Rule