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// graph-permissions · Mail

Mail.SendMicrosoft Graph permission · High risk

Allows the app to send mail as any user without a signed-in user.

Application permission

High risk

Send mail as any user. Allows the app to send mail as any user without a signed-in user.

IDb633e1c5-b582-4048-a93e-9f11b44c7e96
ConsentAlways needs admin consent
RiskAs an application permission this reaches every user's data in the tenant, without anyone signed in.

Delegated permission

Medium risk

Send mail as a user . Allows the app to send mail as users in the organization.

IDe383f46e-2787-4529-855e-0e479a3ffac0
ConsentUsers can consent, if your consent settings allow it
RiskReads or changes the signed-in user's content, limited to what that user can access.

Least-privilege alternative

For application permissions, limit which mailboxes can be sent from with Exchange Online RBAC for applications.

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 "b633e1c5-b582-4048-a93e-9f11b44c7e96"

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 "Mail.Send"

Which apps already have it?

powershell6 lines
# Apps that hold Mail.Send 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 "b633e1c5-b582-4048-a93e-9f11b44c7e96" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for Mail.Send
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 "Mail.Send" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other Mail permissions

Check every app in your tenant → Permission explainer

Sources