Microsoft releases Teams update that fixes emergency calls on Android

Microsoft has released an update for Teams on Android that fixes the emergency calling bug. This new version also undoes any “damage” from previous versions regarding this issue.

It concerns version 1416/1.0.0.2021194504 of the application. The app frees up its input in the TelecomManager part of the Android system when it first runs after an update, which should fix the problem. Android itself, and then specifically version 10 and later, will receive an update to fix the vulnerability. However, it will not be released until January 4, with the Android platform update of that month.

For those who can’t see the update in the Play Store yet and want to make sure that he or she is not vulnerable, Google gives some advice: make sure the Teams app is logged in. If that doesn’t work, reinstalling Teams is also a good method to mitigate the issue. If the app is not logged in, it is still not a certainty that the problem occurs.

The problem arose with an American Reddit user, who then posted about it. His mother had a stroke and he placed an emergency call with his Pixel 3, which runs on Android 11. “My device hung after the line rang once. I could only browse apps while the call was still ringing in the background,” he said. “My phone said my location was being forwarded to emergency services, but I couldn’t hear anyone and tell anyone what was going on.”

Although the affected user is an American, the vulnerability is in the Android component that places an emergency call, for example from the lockscreen. This suggests that the problem is not limited to the United States and can occur in any country.

Rahman and others have written an extensive account of his research into this problem. The problem is that Teams inadvertently registers itself many times as an app capable of making phone calls, including emergency calls. This in itself isn’t a problem yet, but the app did that much more than once over a period of time, causing the registry to fill up and the emergency call system to fail as it did.