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// graph-permissions · Policy

Policy.Read.CrossTenantAccessMicrosoft Graph permission · Low risk

Allows the app to read your organization's cross tenant access policies without a signed-in user.

Application permission

Low risk

Read your organization's cross tenant access policies. Allows the app to read your organization's cross tenant access policies without a signed-in user.

ID8fc84b9a-5c21-479b-ba9d-02d252d062aa
ConsentAlways needs admin consent
RiskRead access, limited to what the signed-in user can see.

Delegated permission

Low risk

Read your organization's cross tenant access policies. Allows the app to read your organization's cross tenant access policies on behalf of the signed-in user.

IDb337372a-8b4d-428d-9cd8-3d7363865736
ConsentNeeds admin consent
RiskRead access, limited to what the signed-in user can see.

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 "8fc84b9a-5c21-479b-ba9d-02d252d062aa"

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 "Policy.Read.CrossTenantAccess"

Which apps already have it?

powershell6 lines
# Apps that hold Policy.Read.CrossTenantAccess 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 "8fc84b9a-5c21-479b-ba9d-02d252d062aa" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for Policy.Read.CrossTenantAccess
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 "Policy.Read.CrossTenantAccess" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other Policy permissions

Check every app in your tenant → Permission explainer

Sources