EnableCertPaddingCheck-CVE-2013-3900.ps1

#=============================================================================================================================
#
# Script Name:      EnableCertPaddingCheck.ps1
# Description:      CVE-2013-3900 mitigation
#                   https://msrc.microsoft.com/update-guide/vulnerability/CVE-2013-3900
# Author:           Danny Chrismas - TheAutisticTechie
#
#=============================================================================================================================
$ErrorActionPreference = 'SilentlyContinue'
$regKey32 = test-path -path "hklm:\Software\Microsoft\Cryptography\Wintrust\Config\"
$regKey64 = test-path -path "hklm:\Software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config\"
$regValue32 = (Get-ItemProperty -Path hklm:\Software\Microsoft\Cryptography\Wintrust\Config\).EnableCertPaddingCheck
$regValue64 = (Get-ItemProperty -Path hklm:\Software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config\).EnableCertPaddingCheck
$ErrorActionPreference = 'stop'

try {
    if((!$regKey32) -and (!$regValue32)) {
        Write-Host "Creating 32-bit reg keys"
        New-Item -Path Registry::HKEY_LOCAL_MACHINE\software\Microsoft\Cryptography\Wintrust\
        New-Item -Path Registry::HKEY_LOCAL_MACHINE\software\Microsoft\Cryptography\Wintrust\Config\
        New-ItemProperty -Path Registry::HKEY_LOCAL_MACHINE\software\Microsoft\Cryptography\Wintrust\Config\ -Name EnableCertPaddingCheck -Value 1
    }

    if((!$regKey64) -and (!$regValue64)) {
        Write-Host "Creating 64-bit reg keys"
        New-Item -Path Registry::HKEY_LOCAL_MACHINE\software\Wow6432Node\Microsoft\Cryptography\Wintrust\
        New-Item -Path Registry::HKEY_LOCAL_MACHINE\software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config\
        New-ItemProperty -Path Registry::HKEY_LOCAL_MACHINE\software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config\ -Name EnableCertPaddingCheck -Value 1
    }

    
    if($regValue32 -ne 1) {
        Write-Host "Correcting 32-bit registry value to 1"
        Set-ItemProperty -Path Registry::HKEY_LOCAL_MACHINE\software\Microsoft\Cryptography\Wintrust\Config\ -Name EnableCertPaddingCheck -Value 1
    }

    if($regValue64 -ne 1) {
        Write-Host "Correcting 64-bit registry value to 1"
        Set-ItemProperty -Path Registry::HKEY_LOCAL_MACHINE\software\Wow6432Node\Microsoft\Cryptography\Wintrust\Config\ -Name EnableCertPaddingCheck -Value 1
    }
    exit 0
}
catch {
    $errMsg = $_.Exception.Message
    Write-Error $errMsg
    exit 1
}