ETW Logging Disabled For rpcrt4.dll

Hunt Hypothesis

Detects changes to the “ExtErrorInformation” key in order to disable ETW logging for rpcrt4.dll

Detection Rule

Sigma (Original)

title: ETW Logging Disabled For rpcrt4.dll
id: 90f342e1-1aaa-4e43-b092-39fda57ed11e
status: test
description: Detects changes to the "ExtErrorInformation" key in order to disable ETW logging for rpcrt4.dll
references:
    - http://redplait.blogspot.com/2020/07/whats-wrong-with-etw.html
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-12-09
modified: 2023-08-17
tags:
    - attack.persistence
    - attack.defense-impairment
    - attack.t1112
    - attack.t1685
logsource:
    product: windows
    category: registry_set
detection:
    selection:
        TargetObject|endswith: '\Microsoft\Windows NT\Rpc\ExtErrorInformation'
        Details:
            # This is disabled by default for some reason
            - 'DWORD (0x00000000)' # Off
            - 'DWORD (0x00000002)' # Off with exceptions
    condition: selection
falsepositives:
    - Unknown
level: low

KQL (Azure Sentinel)

imRegistry
| where RegistryKey endswith "\\Microsoft\\Windows NT\\Rpc\\ExtErrorInformation" and (RegistryValueData in~ ("DWORD (0x00000000)", "DWORD (0x00000002)"))

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where RegistryKey endswith "\\Microsoft\\Windows NT\\Rpc\\ExtErrorInformation" and (RegistryValueData in~ ("DWORD (0x00000000)", "DWORD (0x00000002)"))

Required Data Sources

False Positive Guidance

• Unknown

MITRE ATT&CK Context

• Tactic: Persistence
• Technique: T1112 — T1112
• Technique: T1685 — T1685

References

• http://redplait.blogspot.com/2020/07/whats-wrong-with-etw.html
• SigmaHQ Rule