FCM Messages Blasted out to Teams Customers on Android

We have all been there, one slip of the script and instead of working in the dev environment, you nuke a production server. While this instance isn’t nearly that catastrophic, Microsoft is dealing with an issue of blasting out “Test” messages to Teams users but it’s not entirely clear who is at fault though.

The company is aware of the issue and has indicated that users, only on their mobile device, may receive “Test” notifications that state “FCM Messages Test Notifications” according to TM221041. According to reports on Twitter, these are not one-off instances with reports of up to 10 messages being received. But it may not be Microsoft’s fault (initially), users on Reddit suspect it may be related to Firebase but nothing official is known at this point; Microsoft has stated that this issue only impacts Android users.

If the issue is with Firebase, this is not a vulnerability in Teams but in the notification system for Android. Meaning, it looks like the Android SDK notification service is being hit with the result being non-geniune Teams notifications appearing that are not actually from the Teams app but from a potential weakness in Firebase/Android notification platform.

Christian on Twitter was one such “lucky” recipient and Todd Klindt shared the screenshot you see in this post. If you have users reporting this problem, you are not alone and there is not much that you can do. This is on Microsoft to resolve and hopefully, they will stop sending out these alerts.

While this is not the most significant issue to impact Teams, having test overlap with production is always a bit concerning about what other gremlins are making their way to production; no other major issues for Teams are being reported at this time.

To stay updated on this issue (and any others), login to your admin portal and click Health in the left rail and then on Service health.