Microsoft 365 Android Apps Let Any App Steal Account Tokens via Leftover Debug Flag

A development flag left switched on in production builds of several Microsoft 365 Android apps disabled the check that limits account-token sharing to trusted Microsoft apps.

Any other app on the same phone could ask for the signed-in user's token and get it, then read email, open files, browse the calendar, and send messages as that user. No password, no login screen, no permission prompt.