Windows Event Log Cleared (EventID 104, Microsoft-Windows-Eventlog)

Alerts when Microsoft-Windows-Eventlog reports Event ID 104 for core event log channels, indicating log clearing.

FreeReviewedSigma · High · v2
Product
windows
Service
system
Author
Florian Roth (Nextron Systems), Tim Shelton, Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2022-05-17
Updated
2026-07-31
title: Windows Event Log Cleared (EventID 104, Microsoft-Windows-Eventlog)
id: 78feca32-739a-4e32-884f-1c1a391f831f
related:
  - id: a62b37e0-45d3-48d9-a517-90c1a1b0186b
    type: derived
  - id: 100ef69e-3327-481c-8e5c-6d80d9507556
    type: derived
status: test
description: This rule identifies when a Windows Core Event Log is cleared by matching EventID 104 from the Microsoft-Windows-Eventlog provider. Clearing event logs can help an attacker reduce visibility by removing forensic evidence and weakening detection opportunities. It relies on System logs capturing EventID 104, including the affected Channel information (e.g., Security, System, PowerShell operational logs).
references:
  - https://twitter.com/deviouspolack/status/832535435960209408
  - https://www.hybrid-analysis.com/sample/027cc450ef5f8c5f653329641ec1fed91f694e0d229928963b30f6b0d7d3a745?environmentId=100
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/system/microsoft_windows_eventlog/win_system_susp_eventlog_cleared.yml
author: Florian Roth (Nextron Systems), Tim Shelton, Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2022-05-17
modified: 2023-11-15
tags:
  - attack.defense-impairment
  - attack.t1685.005
  - car.2016-04-002
logsource:
  product: windows
  service: system
detection:
  selection:
    EventID: 104
    Provider_Name: Microsoft-Windows-Eventlog
    Channel:
      - Microsoft-Windows-PowerShell/Operational
      - Microsoft-Windows-Sysmon/Operational
      - PowerShellCore/Operational
      - Security
      - System
      - Windows PowerShell
  condition: selection
falsepositives:
  - Rollout of log collection agents (the setup routine often includes a reset of the local Eventlog)
  - System provisioning (system reset before the golden image creation)
level: high
license: DRL-1.1