[Bug] Crashing Microsoft.Identity.Client.Broker - WithBrokerPreview()

Logs and network traces

During logout:

Ausnahme ausgelöst: "Microsoft.Identity.Client.NativeInterop.MsalRuntimeException" in Microsoft.Identity.Client.NativeInterop.dll
GlobalExceptionHandler: Status: ApiContractViolation
Context: (pii)
Tag: 0x2039c1cb 
Ausnahme ausgelöst: "Microsoft.Identity.Client.NativeInterop.MsalRuntimeException" in Microsoft.Identity.Client.NativeInterop.dll
GlobalExceptionHandler: Status: ApiContractViolation
Context: (pii)
Tag: 0x2039c1cb 

During login:

no logs, app close without any error in VisualStudio. But not always (~70% crash), sometimes login is working.

Which version of MSAL.NET are you using? Microsoft.Identity.Client 4.46.2

Platform .NET 6 WPF

What authentication flow has the issue?

• Desktop / Mobile
  • Interactive
  • Integrated Windows Authentication
  • Username Password
  • Device code flow (browserless)
• Web app
  • Authorization code
  • On-Behalf-Of
• Daemon app
  • Service to Service calls

Is this a new or existing app? This is a new app or experiment.

Repro

readonly string tenantId = "common";
private static string Instance = "https://login.microsoftonline.com/";
readonly string clientId = "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx";
private IPublicClientApplication? _clientApp;
private IPublicClientApplication? PublicClientApp { get { return _clientApp; } }
private static AuthenticationResult? authResult;

...

_clientApp = PublicClientApplicationBuilder.Create(clientId)
                    .WithAuthority($"{Instance}{tenantId}")
                    .WithRedirectUri("http://localhost")
                    .WithBrokerPreview()
                    .Build();

...
authResult = await PublicClientApp.AcquireTokenInteractive(scopes)
                        .WithParentActivityOrWindow(new WindowInteropHelper(window).Handle)
                        .WithUseEmbeddedWebView(true)
                        .ExecuteAsync();
...

//logout
IEnumerable<IAccount> accounts = await PublicClientApp.GetAccountsAsync();
                if (accounts.Any())
                {
                    try
                    {
                        await PublicClientApp.RemoveAsync(accounts.First());
                    }
                    catch (MsalException ex)
                    {
                        Trace.WriteLine($"MsalException Error signing-out user: {ex.Message}");
                    }
                    catch (Exception ex)
                    {
                        Trace.WriteLine($"Exception Error signing-out user: {ex.Message}");
                    }
                }

Expected behavior No crashing app, no errors on logout.

Actual behavior During login, the app is crashing very often, during logout I get errors as above written

Possible solution not using WithBrokerPreview(), instead see alternative code.

Alternative working code same as above, just remove

.WithBrokerPreview()

and you receive the “old” Loginscreen from Microsoft.

[gladjohn]

Hi @pwallner

for the original issue that you see,

GlobalExceptionHandler: Status: ApiContractViolation Context: (pii) Tag: 0x2039c1cb

I am able to repro this when no scopes is passed, this works with the old WAM experience but not the Preview. We will have a fix for this in the next MSAL release

[pwallner]

Hi @gladjohn

This explains # 1 as I read, but not sure if it explains all other points. For now I use the broker (without preview), and there are no errors.