A specific multi-touch gesture bypasses an authentication prompt, allowing anyone to send messages
Picture this. Someone gets hold of your Android phone and, despite not knowing your PIN, they can use Gemini from the lock screen to send SMS or WhatsApp messages as you. This is a real bug and Google says a fix is coming as soon as this week.Since May, The Register has received multiple reports of users bypassing device authentication on Android 16 devices that enable Gemini access from the lock screen.These are distinct from the similar Gemini-based Android lock screen bypass bugs that have made the rounds since September 2025.
One of the bugs reported to us allowed unauthenticated users with physical access to an Android device to enable functionality such as phone, texts, and WhatsApp via Gemini on the lock screen using a specific multi-touch gesture.
When device owners revoke Gemini’s access to certain apps, like Messages, and someone later tries to send an SMS via Gemini on the lock screen, the chatbot will prompt the user to open the relevant app. Selecting "Continue" prompts the user to enter the correct PIN to access messages.However, when “Continue” is pressed simultaneously with Gemini’s “Add attachment” button, the device will then allow unauthenticated users to send that SMS via Gemini, without needing to enter a PIN.From there, users can enable Gemini’s access to other apps, which were previously disconnected from Gemini in the user’s Settings, by invoking the relevant prompt.
