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// graph-permissions · Calendars

Calendars.Read.AllMicrosoft Graph permission · High risk

Allows the app to read work hours and locations settings, recurrences, and occurrences for all users in the organization, without a signed-in user.

Application permission

High risk

Read all users' work hours and locations. Allows the app to read work hours and locations settings, recurrences, and occurrences for all users in the organization, without a signed-in user.

ID470229df-a15a-4b08-9d95-8c534862b362
ConsentAlways needs admin consent
RiskAs an application permission this reaches every user's data in the tenant, without anyone signed in.

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 "470229df-a15a-4b08-9d95-8c534862b362"

Which apps already have it?

powershell6 lines
# Apps that hold Calendars.Read.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 "470229df-a15a-4b08-9d95-8c534862b362" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime

Other Calendars permissions

Check every app in your tenant → Permission explainer

Sources