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Get all permissions granted to an app in Azure AD
<#
.SYNOPSIS
Lists delegated permission grants (OAuth2PermissionGrants) and application permissions grants (AppRoleAssignments) granted to an app.
.PARAMETER ObjectId
The ObjectId of the ServicePrincipal object for the app in question.
.PARAMETER AppId
The AppId of the ServicePrincipal object for the app in question.
.PARAMETER Preload
Whether to preload user and service principals into cache. Useful for processing many apps in small or medium-sized tenants.
.EXAMPLE
PS C:\> .\Get-AzureADPSPermissionGrants.ps1 -AppId "ec70084d-9b61-42bc-b29e-51e1ce39eb39"
Gets all permissions granted to an app, identifying the app by AppId.
.EXAMPLE
PS C:\> .\Get-AzureADPSPermissionGrants.ps1 -ObjectId "73523d04-f9e8-472c-b724-9cf68dcf81b7"
Get all permission granted to an app, identifying the app by ObjectId.
.EXAMPLE
PS C:\> Get-AzureADServicePrincipal -All $true | .\Get-AzureADPSPermissionGrants.ps1 -Preload
Get all granted permissions for all apps in the organization.
#>
[CmdletBinding(DefaultParameterSetName = 'ByObjectId')]
param(
[Parameter(ParameterSetName = 'ByObjectId', Mandatory = $true, ValueFromPipelineByPropertyName = $true)]
$ObjectId,
[Parameter(ParameterSetName = 'ByAppId', Mandatory = $true, ValueFromPipelineByPropertyName = $true)]
$AppId,
[switch] $Preload
)
begin {
# Get tenant details to test that Connect-AzureAD has been called
try {
$tenant_details = Get-AzureADTenantDetail
} catch {
throw "You must call Connect-AzureAD before running this script."
}
Write-Verbose ("TenantId: {0}, InitialDomain: {1}" -f `
$tenant_details.ObjectId, `
($tenant_details.VerifiedDomains | Where-Object { $_.Initial }).Name)
# This bit of magic will let us get a fresh Microsoft Graph access token using the same sesion as the Azure AD PowerShell module
$context = [Microsoft.Open.Azure.AD.CommonLibrary.AzureRmProfileProvider]::Instance.Profile.Context
$showDialogType = [Microsoft.Open.Azure.AD.CommonLibrary.ShowDialog]
$authenticationFactory = [Microsoft.Open.Azure.AD.CommonLibrary.AzureSession]::AuthenticationFactory
$msGraphEndpointResourceId = "MsGraphEndpointResourceId"
$msGraphEndpoint = $context.Environment.Endpoints[$msGraphEndpointResourceId]
$auth = $authenticationFactory.Authenticate($context.Account, $context.Environment, $context.Tenant.Id.ToString(), $null, $showDialogType::Never, $null, $msGraphEndpointResourceId)
# Build the headers used in manual Microsoft Graph requests, including the authorization header
function GetHeaders {
return @{
# This returns the authorization header value with a fresh access token
"Authorization" = $script:auth.AuthorizeRequest($script:msGraphEndpointResourceId)
}
}
# Make a GET request to Microsoft Graph and (optionally) page through the results
function Get ($Query, [switch]$All) {
do {
$morePages = $false
$result = Invoke-WebRequest -Method "Get" -Headers (GetHeaders) -Uri $Query
if ($result -ne $null) {
$r = $result.Content | ConvertFrom-Json
if ("value" -in $r.PSObject.Properties.Name -and $r.value -is [array]) {
$r.value
if ($All -and $r.'@odata.nextLink') {
$Query = $r.'@odata.nextLink'
$morePages = $true
}
} else {
$r
}
}
} while ($morePages)
}
# Function to get appRoleAssignments from Microsoft Graph. We use Microsoft Graph because it avoids
# having to sort out behavior differences in Get-AzureADServiceAppRoleAssignedTo and Get-AzureADServiceAppRoleAssignment
function GetServicePrincipalAppRoleAssignments($PrincipalId) {
Get -Query ("{0}/v1.0/servicePrincipals/{1}/appRoleAssignments" -f $script:msGraphEndpoint, $PrincipalId) -All
}
# An in-memory cache of objects by {object ID} and by {object class, object ID}
$script:ObjectByObjectId = @{}
$script:ObjectByObjectClassId = @{}
# Function to add an object to the cache
function CacheObject($Object) {
if ($Object) {
if (-not $script:ObjectByObjectClassId.ContainsKey($Object.ObjectType)) {
$script:ObjectByObjectClassId[$Object.ObjectType] = @{}
}
$script:ObjectByObjectClassId[$Object.ObjectType][$Object.ObjectId] = $Object
$script:ObjectByObjectId[$Object.ObjectId] = $Object
}
}
# Function to retrieve an object from the cache (if it's there), or from Azure AD (if not).
function GetObjectByObjectId($ObjectId) {
Write-Debug ("GetObjectByObjectId: ObjectId: '{0}'" -f $ObjectId)
if (-not $script:ObjectByObjectId.ContainsKey($ObjectId)) {
Write-Verbose ("Querying Azure AD for object '{0}'" -f $ObjectId)
$object = Get-AzureADObjectByObjectId -ObjectId $ObjectId
if ($object) {
CacheObject -Object $object
} else {
throw ("Object not found for ObjectId: '{0}'" -f $ObjectId)
}
}
return $script:ObjectByObjectId[$ObjectId]
}
$cache_preloaded = $false
$behavior = $null
}
process {
# Retrieve the client ServicePrincipal object (which also ensures it actually exists)
if ($PSCmdlet.ParameterSetName -eq "ByObjectId") {
try {
$client = GetObjectByObjectId -ObjectId $ObjectId
} catch {
Write-Error ("Unable to retrieve client ServicePrincipal object by ObjectId: '{0}'" -f $ObjectId)
throw $_
}
} elseif ($PSCmdlet.ParameterSetName -eq "ByAppId") {
try {
$client = Get-AzureADServicePrincipal -Filter ("appId eq '{0}'" -f $AppId)
CacheObject -Object $client
} catch {
Write-Error ("Unable to retrieve client ServicePrincipal object by AppId: '{0}'" -f $AppId)
throw $_
}
}
Write-Verbose ("Client DisplayName: '{0}', ObjectId: '{1}, AppId: '{2}'" -f $client.DisplayName, $client.ObjectId, $client.AppId)
# Get one page of User objects and one of ServicePrincipal objects, and add to the cache. For smaller tenants,
# this avoids a large number of requests to get individual objects. This behavior can be skipped with -NoPreload,
# in which the first time each object is needed it will be requested and loaded into the cache.
if (($Preload) -and (-not $cache_preloaded)) {
Write-Verbose ("Retrieving a page of User objects and a page of ServicePrincipal objects...")
Get-AzureADServicePrincipal -Top 999 | ForEach-Object { CacheObject -Object $_ }
Get-AzureADUser -Top 999 | ForEach-Object { CacheObject -Object $_ }
$cache_preloaded = $true
}
# Get all delegated permission grants
Write-Verbose "Retrieving delegated permission grants..."
Get-AzureADServicePrincipalOAuth2PermissionGrant -ObjectId $client.ObjectId | ForEach-Object {
$grant = $_
if ($grant.Scope) {
$grant.Scope.Split(" ") | Where-Object { $_ } | ForEach-Object {
$scope = $_
$resource = GetObjectByObjectId -ObjectId $grant.ResourceId
$permission = $resource.OAuth2Permissions | Where-Object { $_.Value -eq $scope }
$principalDisplayName = ""
if ($grant.PrincipalId) {
$principal = GetObjectByObjectId -ObjectId $grant.PrincipalId
$principalDisplayName = $principal.DisplayName
}
return New-Object PSObject -Property ([ordered]@{
"PermissionType" = "Delegated"
"ClientObjectId" = $grant.ClientId
"ClientDisplayName" = $client.DisplayName
"ResourceObjectId" = $grant.ResourceId
"ResourceDisplayName" = $resource.DisplayName
"Permission" = $scope
"PermissionId" = $permission.Id
"PermissionDisplayName" = $permission.AdminConsentDisplayName
"PermissionDescription" = $permission.AdminConsentDescription
"ConsentType" = $grant.ConsentType
"PrincipalObjectId" = $grant.PrincipalId
"PrincipalDisplayName" = $principalDisplayName
"PermissionGrantId" = $grant.ObjectId
})
}
}
}
# Get all application permission grants
Write-Verbose "Retrieving app role assignments..."
GetServicePrincipalAppRoleAssignments -PrincipalId $client.ObjectId | ForEach-Object {
$assignment = $_
$resource = GetObjectByObjectId -ObjectId $assignment.resourceId
$appRole = $resource.AppRoles | Where-Object { $_.Id -eq $assignment.appRoleId }
return New-Object PSObject -Property ([ordered]@{
"PermissionType" = "Application"
"ClientObjectId" = $assignment.principalId
"ClientDisplayName" = $client.DisplayName
"ResourceObjectId" = $assignment.resourceId
"ResourceDisplayName" = $resource.DisplayName
"Permission" = $appRole.Value
"PermissionId" = $assignment.appRoleId
"PermissionDisplayName" = $appRole.DisplayName
"PermissionDescription" = $appRole.Description
"PermissionGrantId" = $assignment.id
})
}
}
@RameshSubramanyamvari

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@RameshSubramanyamvari RameshSubramanyamvari commented Feb 18, 2021

Error

script not Fetching the ClientDisplayName (Application name) ("ClientDisplayName" = $client.DisplayName) for application permissions. how to resolve this???

@psignoret

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@psignoret psignoret commented Feb 24, 2021

@RameshSubramanyamvari Thanks for bringing this up! I tracked this down to an issue in how the script was detecting if the module was running as the default Microsoft Azure AD PowerShell app or as a customer third-party app.

I've updated the script to use a different approach, which should solve this problem.

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