Exclusive: How One Line of Code Put Billions of Microsoft Android App Downloads at Risk

https://www.securityweek.com/wp-content/uploads/2026/06/Android-Microsoft_Apps-Flaw.jpg

Six Microsoft 365 Android apps contain an identical flaw that could risk billions of downloads being compromised.

The findings, shared exclusively with SecurityWeek ahead of the expected public release of the research on Tuesday, were uncovered by Enclave, an AI-powered exploitable bug hunter. It is nothing more than a single debug flag being left in the production code of Word, PowerPoint, Excel, Microsoft 365 Copilot, Microsoft Loop and OneNote for Android. Someone left debug mode enabled in production: – set IsDebugMode(true). This was enabled across all six apps, but was not enabled in other Microsoft (MS) apps such as Teams. These were not affected by any consequent potential exploitation attempt.

The effect of such debug flags varies. Sometimes the purpose is simply to affect logging or to test output. “This one changed the behavior around account access token sharing,” explains Enclave reporting its findings. “With debug mode enabled, the protection...

Copyright of this story solely belongs to securityweek.com. To see the full text click HERE

Read more