How to Configure UAC Settings for Windows (PowerShell Script)

User Account Control (UAC) is a vital security feature in Windows operating systems. It acts as a gatekeeper, preventing unauthorized changes to your computer. UAC works by defining different levels of user permissions, ranging from always notifying about changes to never notifying. By understanding these levels and how they affect user permissions, IT professionals can better secure their systems.

Background

Introduced with Windows Vista, UAC has been a cornerstone of Windows security. When certain changes are attempted, UAC prompts users for permission or an administrator password before allowing the task to proceed. This script, tailored for Windows 7 and Windows Server 2012 onwards, offers a way to programmatically configure these UAC settings.

The Script

#Requires -Version 2.0

<#
.SYNOPSIS
    Configures UAC.
.DESCRIPTION
    Configures UAC to defaults if no parameters are specified.
.EXAMPLE
    No parameters needed.
    Sets all UAC settings to Microsoft's defaults.
.EXAMPLE
     -ConsentPromptBehaviorAdmin 5
    Sets ConsentPromptBehaviorAdmin to 5
.EXAMPLE
    PS C:> Set-Uac.ps1
    Sets all UAC settings to MS defaults.
.OUTPUTS
    None
.NOTES
    Minimum OS Architecture Supported: Windows 7, Windows Server 2012
    This script will show before and after UAC settings.
    Release Notes:
    Initial Release
By using this script, you indicate your acceptance of the following legal terms as well as our Terms of Use at https://www.ninjaone.com/terms-of-use.
    Ownership Rights: NinjaOne owns and will continue to own all right, title, and interest in and to the script (including the copyright). NinjaOne is giving you a limited license to use the script in accordance with these legal terms. 
    Use Limitation: You may only use the script for your legitimate personal or internal business purposes, and you may not share the script with another party. 
    Republication Prohibition: Under no circumstances are you permitted to re-publish the script in any script library or website belonging to or under the control of any other software provider. 
    Warranty Disclaimer: The script is provided “as is” and “as available”, without warranty of any kind. NinjaOne makes no promise or guarantee that the script will be free from defects or that it will meet your specific needs or expectations. 
    Assumption of Risk: Your use of the script is at your own risk. You acknowledge that there are certain inherent risks in using the script, and you understand and assume each of those risks. 
    Waiver and Release: You will not hold NinjaOne responsible for any adverse or unintended consequences resulting from your use of the script, and you waive any legal or equitable rights or remedies you may have against NinjaOne relating to your use of the script. 
    EULA: If you are a NinjaOne customer, your use of the script is subject to the End User License Agreement applicable to you (EULA).
.COMPONENT
    LocalUserAccountManagement
#>

[CmdletBinding()]
param (
    [Parameter()][ValidateRange(0, 5)][int]$ConsentPromptBehaviorAdmin = 5,
    [Parameter()][ValidateRange(0, 3)][int]$ConsentPromptBehaviorUser = 3,
    [Parameter()][ValidateRange(0, 1)][int]$EnableInstallerDetection = 1,
    [Parameter()][ValidateRange(0, 1)][int]$EnableLUA = 1,
    [Parameter()][ValidateRange(0, 1)][int]$EnableVirtualization = 1,
    [Parameter()][ValidateRange(0, 1)][int]$PromptOnSecureDesktop = 1,
    [Parameter()][ValidateRange(0, 1)][int]$ValidateAdminCodeSignatures = 0,
    [Parameter()][ValidateRange(0, 1)][int]$FilterAdministratorToken = 0
)

begin {
    function Test-IsElevated {
        $id = [System.Security.Principal.WindowsIdentity]::GetCurrent()
        $p = New-Object System.Security.Principal.WindowsPrincipal($id)
        if ($p.IsInRole([System.Security.Principal.WindowsBuiltInRole]::Administrator))
        { Write-Output $true }
        else
        { Write-Output $false }
    }
    function Set-ItemProp {
        param (
            $Path,
            $Name,
            $Value,
            [ValidateSet("DWord", "QWord", "String", "ExpandedString", "Binary", "MultiString", "Unknown")]
            $PropertyType = "DWord"
        )
        if ((Get-ItemProperty -Path $Path -Name $Name -ErrorAction SilentlyContinue)) {
            Set-ItemProperty -Path $Path -Name $Name -Value $Value -Force -Confirm:$false | Out-Null
        }
        else {
            New-ItemProperty -Path $Path -Name $Name -Value $Value -PropertyType $PropertyType -Force -Confirm:$false | Out-Null
        }
    }
}
process {
    if (-not (Test-IsElevated)) {
        Write-Error -Message "Access Denied. Please run with Administrator privileges."
        exit 1
    }
    $path = "HKLM:SOFTWAREMicrosoftWindowsCurrentVersionPoliciesSystem"
    $filter = "ConsentPromptBehaviorAdmin|ConsentPromptBehaviorUser|EnableInstallerDetection|EnableLUA|EnableVirtualization|PromptOnSecureDesktop|ValidateAdminCodeSignatures|FilterAdministratorToken"
    Write-Host "Before:"
    (Get-ItemProperty $path).psobject.properties | Where-Object { $_.name -match $filter } | Select-Object name, value

    try {
        $filter -split '|' | ForEach-Object {
            Set-ItemProp -Path $Path -Name $_ -Value (Get-Variable -Name $_).Value
        }
    }
    catch {
        Write-Error $_
        exit 1
    }

    Write-Host "After:"
    (Get-ItemProperty $path).psobject.properties | Where-Object { $_.name -match $filter } | Select-Object name, value
}
end {}

 

Potential Use Cases

Consider a scenario where a company is deploying new software that requires specific UAC settings for optimal performance and security. Instead of manually configuring each computer, the IT team can use this script to ensure every machine is set up correctly. Additionally, for companies that need to adhere to strict security regulations, this script can help ensure compliance by standardizing UAC settings across the board.

FAQs

• Which operating systems support this script?
  The script is designed for Windows 7, Windows Server 2012, and later versions.
• What permissions are required to run the script?
  The script must be run with administrative privileges.
• Are there risks associated with using this script?
  As with any script that modifies system settings, there’s a potential for unintended consequences. Always back up and test before widespread deployment.

Security Implications

UAC settings play a pivotal role in system security. Incorrect settings can inadvertently give malware the green light to install or run without user permission. By automating the configuration process, this script reduces the chances of human error but underscores the importance of understanding each setting’s implications.

Recommendations

• Always backup the registry before making changes to safeguard against potential issues.
• Test the script on a single machine or in a controlled environment before deploying it network-wide.
• Stay updated on best practices for UAC settings to ensure optimal security.

Final Thoughts

In the ever-evolving landscape of IT security, tools like this UAC configuration script are invaluable. By understanding and leveraging such tools, IT professionals can ensure a more secure and efficient environment for their users.