WMI Privilages for a non-administrator user using Powershell

To provide WMI privilages for a non administrator user. Supply the username and required permissions as parameters.

Script
<#
.SYNOPSIS
This script can be used to provide WMI privilages to a non administrator user account.
.DESCRIPTION
This script can be used to provide WMI privilages to a non administrator user account.
.EXAMPLE
C:\PS>.\Set-WmiNamespaceSecurity.ps1 root add nonadmin@mslync10.com Enable,RemoteAccess,MethodExecute,ReadSecurity
Provides execute method, enable account, remote enable and read security for user ‘nonadmin’.
#>

Param ( [parameter(Mandatory=$true,Position=0)][string] $namespace,
[parameter(Mandatory=$true,Position=1)][string] $operation,
[parameter(Mandatory=$true,Position=2)][string] $account,
[parameter(Position=3)][string[]] $permissions = $null,
[bool] $allowInherit = $false,
[bool] $deny = $false,
[string] $computerName = “.”,
[System.Management.Automation.PSCredential] $credential = $null)Process
{
$ErrorActionPreference = “Stop”Function Get-AccessMaskFromPermission($permissions)
{
$WBEM_ENABLE = 1
$WBEM_METHOD_EXECUTE = 2
$WBEM_FULL_WRITE_REP = 4
$WBEM_PARTIAL_WRITE_REP = 8
$WBEM_WRITE_PROVIDER = 0x10
$WBEM_REMOTE_ACCESS = 0x20
$WBEM_RIGHT_SUBSCRIBE = 0x40
$WBEM_RIGHT_PUBLISH = 0x80
$READ_CONTROL = 0x20000
$WRITE_DAC = 0x40000$WBEM_RIGHTS_FLAGS = $WBEM_ENABLE,$WBEM_METHOD_EXECUTE,$WBEM_FULL_WRITE_REP,`
$WBEM_PARTIAL_WRITE_REP,$WBEM_WRITE_PROVIDER,$WBEM_REMOTE_ACCESS,`
$READ_CONTROL,$WRITE_DAC
$WBEM_RIGHTS_STRINGS = “Enable”,”MethodExecute”,”FullWrite”,”PartialWrite”,`
“ProviderWrite”,”RemoteAccess”,”ReadSecurity”,”WriteSecurity”
$permissionTable = @{}
for ($i = 0; $i -lt $WBEM_RIGHTS_FLAGS.Length; $i++) {
$permissionTable.Add($WBEM_RIGHTS_STRINGS[$i].ToLower(), $WBEM_RIGHTS_FLAGS[$i])
}
$accessMask = 0
foreach ($permission in $permissions) {
if (-not $permissionTable.ContainsKey($permission.ToLower())) {
throw “Unknown permission: $permission`nValid permissions: $($permissionTable.Keys)”
}
$accessMask += $permissionTable[$permission.ToLower()]
}
$accessMask
}
if ($PSBoundParameters.ContainsKey(“Credential”)) {
$remoteparams = @{ComputerName=$computer;Credential=$credential}
} else {
$remoteparams = @{ComputerName=$computerName}
}
$invokeparams = @{Namespace=$namespace;Path=”__systemsecurity=@”} + $remoteParams
$output = Invoke-WmiMethod @invokeparams -Name GetSecurityDescriptor
if ($output.ReturnValue -ne 0) {
throw “GetSecurityDescriptor failed: $($output.ReturnValue)”
}
$acl = $output.Descriptor
$OBJECT_INHERIT_ACE_FLAG = 0x1
$CONTAINER_INHERIT_ACE_FLAG = 0x2
$computerName = (Get-WmiObject @remoteparams Win32_ComputerSystem).Name
if ($account.Contains(‘\’)) {
$domainaccount = $account.Split(‘\’)
$domain = $domainaccount[0]
if (($domain -eq “.”) -or ($domain -eq “BUILTIN”)) {
$domain = $computerName
}
$accountname = $domainaccount[1]
}
elseif ($account.Contains(‘@’)) {
$domainaccount = $account.Split(‘@’)
$domain = $domainaccount[1].Split(‘.’)[0]
$accountname = $domainaccount[0]
}
else {
$domain = $computerName
$accountname = $account
}
$getparams = @{Class=”Win32_Account”;Filter=”Domain=’$domain’ and Name=’$accountname'”}
$win32account = Get-WmiObject @getparams
if ($win32account -eq $null) {
throw “Account was not found: $account”
}
switch ($operation) {
“add” {
if ($permissions -eq $null) {
throw “-Permissions must be specified for an add operation”
}
$accessMask = Get-AccessMaskFromPermission($permissions)
$ace = (New-Object System.Management.ManagementClass(“win32_Ace”)).CreateInstance()
$ace.AccessMask = $accessMask
if ($allowInherit) {
$ace.AceFlags = $OBJECT_INHERIT_ACE_FLAG + $CONTAINER_INHERIT_ACE_FLAG
}
else {
$ace.AceFlags = 0
}
$trustee = (New-Object System.Management.ManagementClass(“win32_Trustee”)).CreateInstance()
$trustee.SidString = $win32account.Sid
$ace.Trustee = $trustee$ACCESS_ALLOWED_ACE_TYPE = 0x0
$ACCESS_DENIED_ACE_TYPE = 0x1if ($deny) {
$ace.AceType = $ACCESS_DENIED_ACE_TYPE
}
else {
$ace.AceType = $ACCESS_ALLOWED_ACE_TYPE
}$acl.DACL += $ace.psobject.immediateBaseObject
}
“delete” {
if ($permissions -ne $null) {
throw “Permissions cannot be specified for a delete operation”
}
[System.Management.ManagementBaseObject[]]$newDACL = @()
foreach ($ace in $acl.DACL) {
if ($ace.Trustee.SidString -ne $win32account.Sid) {
$newDACL += $ace.psobject.immediateBaseObject
}
}$acl.DACL = $newDACL.psobject.immediateBaseObject
}
default {
throw “Unknown operation: $operation`nAllowed operations: add delete”
}
}
$setparams = @{Name=”SetSecurityDescriptor”;ArgumentList=$acl.psobject.immediateBaseObject} + $invokeParams
$output = Invoke-WmiMethod @setparams
if ($output.ReturnValue -ne 0) {
throw “SetSecurityDescriptor failed: $($output.ReturnValue)”
}
}

Output

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