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// graph-permissions · Chat

Chat.ReadWrite.AllMicrosoft Graph permission · High risk

Allows an app to read and write all chat messages in Microsoft Teams, without a signed-in user.

Application permission

High risk

Read and write all chat messages. Allows an app to read and write all chat messages in Microsoft Teams, without a signed-in user.

ID294ce7c9-31ba-490a-ad7d-97a7d075e4ed
ConsentAlways needs admin consent
RiskAs an application permission this reaches every user's data in the tenant, without anyone signed in.

Delegated permission

High risk

Read and write all chat messages. Allows an app to read and write all one-to-one and group chats in Microsoft Teams, without a signed-in user. Does not allow sending messages.

ID7e9a077b-3711-42b9-b7cb-5fa5f3f7fea7
ConsentNeeds admin consent
RiskCan change data across the whole tenant.

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 "294ce7c9-31ba-490a-ad7d-97a7d075e4ed"

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 "Chat.ReadWrite.All"

Which apps already have it?

powershell6 lines
# Apps that hold Chat.ReadWrite.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 "294ce7c9-31ba-490a-ad7d-97a7d075e4ed" |
    Select-Object PrincipalDisplayName, PrincipalId, CreatedDateTime
powershell6 lines
# Apps with delegated consent for Chat.ReadWrite.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 "Chat.ReadWrite.All" } |
    Select-Object ClientId, ConsentType, PrincipalId

Other Chat permissions

Check every app in your tenant → Permission explainer

Sources