T1685.005Clear Windows Event Logs

Adversaries may clear Windows Event Logs to hide the activity of an intrusion. Windows Event Logs are a record of a computer's alerts and notifications. There are three system-defined sources of events: System, Application, and Security, with five event types: Error, Warning, Information, Success Audit, and Failure Audit.

With administrator privileges, the event logs can be cleared with the following utility commands:

* `wevtutil cl system`
* `wevtutil cl application`
* `wevtutil cl security`

These logs may also be cleared through other mechanisms, such as the event viewer GUI or [PowerShell](https://attack.mitre.org/techniques/T1059/001). For example, adversaries may use the PowerShell command `Remove-EventLog -LogName Security` to delete the Security EventLog and after reboot, disable future logging. Note: events may still be generated and logged in the .evtx file between the time the command is run and the reboot.(Citation: disable_win_evt_logging)

Adversaries may also attempt to clear logs by directly deleting the stored log files within `C:\Windows\System32\winevt\logs\`.