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// graph-permissions · CustomAuthenticationExtension

CustomAuthenticationExtension.ReadWrite.AllMicrosoft Graph permission · High risk

Allows the app to read or write your organization's custom authentication extensions without a signed-in user.

Application permission

High risk

Read and write all custom authentication extensions. Allows the app to read or write your organization's custom authentication extensions without a signed-in user.

IDc2667967-7050-4e7e-b059-4cbbb3811d03
ConsentAlways needs admin consent
RiskCan change data across the whole tenant.

Delegated permission

High risk

Read and write your organization's custom authentication extensions. Allows the app to read or write your organization's custom authentication extensions on behalf of the signed-in user.

ID8dfcf82f-15d0-43b3-bc78-a958a13a5792
ConsentNeeds admin consent
RiskCan change data across the whole tenant.

Grant it to an app

In the portal: App registrations › your app › API permissions › Add a permission › Microsoft Graph › Application permissions, then grant admin consent. Or with Graph PowerShell:

powershell5 lines
Connect-MgGraph -Scopes "Application.Read.All", "AppRoleAssignment.ReadWrite.All"
$graph = Get-MgServicePrincipal -Filter "appId eq '00000003-0000-0000-c000-000000000000'"
$app   = Get-MgServicePrincipal -Filter "appId eq '<your app's client id>'"
New-MgServicePrincipalAppRoleAssignment -ServicePrincipalId $app.Id `
    -PrincipalId $app.Id -ResourceId $graph.Id -AppRoleId "c2667967-7050-4e7e-b059-4cbbb3811d03"

Ask for it when signing in

Delegated permissions act as the signed-in user, so the app can never do more than that user can.

powershell1 line
Connect-MgGraph -Scopes "CustomAuthenticationExtension.ReadWrite.All"

Which apps already have it?

powershell6 lines
# Apps that hold CustomAuthenticationExtension.ReadWrite.All as an application permission
Connect-MgGraph -Scopes "Application.Read.All"
$graph = Get-MgServicePrincipal -Filter "appId eq '00000003-0000-0000-c000-000000000000'"
Get-MgServicePrincipalAppRoleAssignedTo -ServicePrincipalId $graph.Id -All |
    Where-Object AppRoleId -eq "c2667967-7050-4e7e-b059-4cbbb3811d03" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for CustomAuthenticationExtension.ReadWrite.All
Connect-MgGraph -Scopes "Application.Read.All", "Directory.Read.All"
$graph = Get-MgServicePrincipal -Filter "appId eq '00000003-0000-0000-c000-000000000000'"
Get-MgOauth2PermissionGrant -All |
    Where-Object { $_.ResourceId -eq $graph.Id -and ($_.Scope -split " ") -contains "CustomAuthenticationExtension.ReadWrite.All" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other CustomAuthenticationExtension permissions

Check every app in your tenant → Permission explainer

Sources