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// graph-permissions · Mail

Mail.ReadBasicMicrosoft Graph permission · High risk

Allows the app to read basic mail properties in all mailboxes without a signed-in user. Includes all properties except body, previewBody, attachments and any extended properties.

Application permission

High risk

Read basic mail in all mailboxes. Allows the app to read basic mail properties in all mailboxes without a signed-in user. Includes all properties except body, previewBody, attachments and any extended properties.

ID6be147d2-ea4f-4b5a-a3fa-3eab6f3c140a
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

Read user basic mail. Allows the app to read email in the signed-in user's mailbox except body, previewBody, attachments and any extended properties.

IDa4b8392a-d8d1-4954-a029-8e668a39a170
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.

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 "6be147d2-ea4f-4b5a-a3fa-3eab6f3c140a"

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.ReadBasic"

Which apps already have it?

powershell6 lines
# Apps that hold Mail.ReadBasic 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 "6be147d2-ea4f-4b5a-a3fa-3eab6f3c140a" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for Mail.ReadBasic
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.ReadBasic" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other Mail permissions

Check every app in your tenant → Permission explainer

Sources