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Files.Read.AllMicrosoft Graph permission · High risk

Allows the app to read all files in all site collections without a signed in user.

Application permission

High risk

Read files in all site collections. Allows the app to read all files in all site collections without a signed in user.

ID01d4889c-1287-42c6-ac1f-5d1e02578ef6
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 all files that user can access. Allows the app to read all files the signed-in user can access.

IDdf85f4d6-205c-4ac5-a5ea-6bf408dba283
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

Use Sites.Selected, or delegated Files.Read for the user's own files.

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 "01d4889c-1287-42c6-ac1f-5d1e02578ef6"

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 "Files.Read.All"

Which apps already have it?

powershell6 lines
# Apps that hold Files.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 "01d4889c-1287-42c6-ac1f-5d1e02578ef6" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for Files.Read.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 "Files.Read.All" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other Files permissions

Check every app in your tenant → Permission explainer

Sources