Disable Windows Event Logging Via Registry — Sigma Rule

Rule metadata and linked tags

Author: frack113, Nasreddine Bencherchali (Nextron Systems). Source status: test; severity: high. Source dates: 2022-07-04 / 2024-03-25.

{
  "category": "registry_set",
  "product": "windows"
}

Pinned original Sigma rule · Detection Rule License 1.1

Source SHA-256: 2d8718ab6e4692fa0afd9210cae634fb54beb7d7e921c4c8e5bd0ba4711be2c4

Detection logic

Original source YAML. Source-tag agreement is not proof of complete semantic coverage. This rule has not been compiled for a SIEM backend or validated against live telemetry here.

title: Disable Windows Event Logging Via Registry
id: 2f78da12-f7c7-430b-8b19-a28f269b77a3
status: test
description: Detects tampering with the "Enabled" registry key in order to disable Windows logging of a Windows event channel
references:
    - https://twitter.com/WhichbufferArda/status/1543900539280293889
    - https://github.com/DebugPrivilege/CPP/blob/c39d365617dbfbcb01fffad200d52b6239b2918c/Windows%20Defender/RestoreDefenderConfig.cpp
author: frack113, Nasreddine Bencherchali (Nextron Systems)
date: 2022-07-04
modified: 2024-03-25
tags:
    - attack.defense-impairment
    - attack.t1685.001
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains: '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\'
        TargetObject|endswith: '\Enabled'
        Details: 'DWORD (0x00000000)'
    filter_main_wevutil:
        Image: 'C:\Windows\system32\wevtutil.exe' # FP generated during installation of manifests via wevtutil
    filter_main_iis:
        Image|startswith: 'C:\Windows\winsxs\'
        Image|endswith: '\TiWorker.exe'  # Many different TargetObjects
    filter_main_svchost:
        Image: 'C:\Windows\System32\svchost.exe'
        TargetObject|contains:
            - '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-FileInfoMinifilter'
            - '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-ASN1\'
            - '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-Kernel-AppCompat\'
            - '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-Runtime\Error\'
            - '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-CAPI2/Operational\'
    filter_main_trusted_installer:
        Image: C:\Windows\servicing\TrustedInstaller.exe
        TargetObject|contains: '\Microsoft\Windows\CurrentVersion\WINEVT\Channels\Microsoft-Windows-Compat-Appraiser'
    filter_optional_empty: # This filter is related to aurora. Should be removed when fix is deployed. # TODO: Remove later
        Image: ''
    filter_optional_null: # This filter is related to aurora. Should be removed when fix is deployed. # TODO: Remove later
        Image: null
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
falsepositives:
    - Rare falsepositives may occur from legitimate administrators disabling specific event log for troubleshooting
level: high

Original YAML and metadata in JSON

False positives

• Rare falsepositives may occur from legitimate administrators disabling specific event log for troubleshooting

Source references

• https://twitter.com/WhichbufferArda/status/1543900539280293889
• https://github.com/DebugPrivilege/CPP/blob/c39d365617dbfbcb01fffad200d52b6239b2918c/Windows%20Defender/RestoreDefenderConfig.cpp