# T1491.001 - Internal Defacement
## [Description from ATT&CK](https://attack.mitre.org/techniques/T1491/001)
<blockquote>An adversary may deface systems internal to an organization in an attempt to intimidate or mislead users. This may take the form of modifications to internal websites, or directly to user systems with the replacement of the desktop wallpaper.(Citation: Novetta Blockbuster) Disturbing or offensive images may be used as a part of [Internal Defacement](https://attack.mitre.org/techniques/T1491/001) in order to cause user discomfort, or to pressure compliance with accompanying messages. Since internally defacing systems exposes an adversary's presence, it often takes place after other intrusion goals have been accomplished.(Citation: Novetta Blockbuster Destructive Malware)</blockquote>

## Atomic Tests

- [Atomic Test #1 - Replace Desktop Wallpaper](#atomic-test-1---replace-desktop-wallpaper)


<br/>

## Atomic Test #1 - Replace Desktop Wallpaper
Downloads an image from a URL and sets it as the desktop wallpaper.

**Supported Platforms:** Windows


**auto_generated_guid:** 30558d53-9d76-41c4-9267-a7bd5184bed3





#### Inputs:
| Name | Description | Type | Default Value |
|------|-------------|------|---------------|
| url_of_wallpaper | URL pointing to the image file you wish to set as wallpaper | Url | https://redcanary.com/wp-content/uploads/Atomic-Red-Team-Logo.png|
| pointer_to_orginal_wallpaper | Full path to where a file containing the original wallpaper location will be saved | String | $env:TEMP&#92;T1491.001-OrginalWallpaperLocation|
| wallpaper_location | Full path to where the downloaded wallpaper image will be saved | String | $env:TEMP&#92;T1491.001-newWallpaper.png|


#### Attack Commands: Run with `powershell`! 


```powershell
$url = "#{url_of_wallpaper}"
$imgLocation = "#{wallpaper_location}"
$orgWallpaper = (Get-ItemProperty -Path Registry::'HKEY_CURRENT_USER\Control Panel\Desktop\' -Name WallPaper).WallPaper
$orgWallpaper | Out-File -FilePath "#{pointer_to_orginal_wallpaper}"
$updateWallpapercode = @' 
using System.Runtime.InteropServices; 
namespace Win32{

    public class Wallpaper{ 
        [DllImport("user32.dll", CharSet=CharSet.Auto)] 
         static extern int SystemParametersInfo (int uAction , int uParam , string lpvParam , int fuWinIni) ; 
         
         public static void SetWallpaper(string thePath){ 
            SystemParametersInfo(20,0,thePath,3); 
        }
    }
} 
'@
$wc = New-Object System.Net.WebClient  
try{  
    $wc.DownloadFile($url, $imgLocation)
    add-type $updateWallpapercode 
    [Win32.Wallpaper]::SetWallpaper($imgLocation)
} 
catch [System.Net.WebException]{  
    Write-Host("Cannot download $url") 
    add-type $updateWallpapercode 
    [Win32.Wallpaper]::SetWallpaper($imgLocation)
} 
finally{    
    $wc.Dispose()  
}
```

#### Cleanup Commands:
```powershell
$updateWallpapercode = @' 
using System.Runtime.InteropServices; 
namespace Win32{

    public class Wallpaper{ 
        [DllImport("user32.dll", CharSet=CharSet.Auto)] 
         static extern int SystemParametersInfo (int uAction , int uParam , string lpvParam , int fuWinIni) ; 
         
         public static void SetWallpaper(string thePath){ 
            SystemParametersInfo(20,0,thePath,3); 
        }
    }
} 
'@
if (Test-Path -Path #{pointer_to_orginal_wallpaper} -PathType Leaf) {
     $orgImg = Get-Content -Path "#{pointer_to_orginal_wallpaper}"
     add-type $updateWallpapercode 
     [Win32.Wallpaper]::SetWallpaper($orgImg)
}
Remove-Item "#{pointer_to_orginal_wallpaper}" -ErrorAction Ignore
Remove-Item "#{wallpaper_location}" -ErrorAction Ignore
```





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