Your Android lock screen is supposed to keep your messages safe, even if someone gets hold of your phone. But a newly discovered Gemini bug could do the opposite. Since May, The Register has received multiple reports of people bypassing device authentication on Android 16 devices that allow Gemini access straight from the lock screen.
The flaw lets anyone use Gemini to send SMS and even WhatsApp messages without ever entering your PIN. It only works under specific conditions, but it is serious enough that Google has confirmed a fix is already rolling out.
How does the Gemini bug bypass your Android PIN?
The exploit comes down to a very specific move. Normally, if you have revoked Gemini’s access to Messages, asking it to send a text from the lock screen prompts you to open the app, which then correctly asks for your PIN. But pressing Continue at the exact same moment as Gemini’s Add Attachment button breaks that safeguard entirely, letting the SMS go through with zero authentication.
From there, things get worse. Typing something like @WhatsApp into Gemini’s text field can silently reconnect apps you had previously disconnected, again without ever requiring your PIN. As shown in the video below, checking your settings afterward would show WhatsApp linked to Gemini as if you had approved it yourself.
How risky is this, and what should you do about it?
The exploit requires someone to physically possess your phone, making it less dangerous than a remote attack. Even so, researchers warned it could be abused in phone theft cases, allowing thieves to send convincing messages from your number before you regain control of your device.
Interestingly, this bug is not limited to Pixel devices either, though some users reported being unable to reproduce it on Samsung phones. Google has yet to clarify exactly which manufacturers or models remain vulnerable.
Google also said it was already aware of the issue and scheduled a full fix for deployment this week. Until that update reaches your phone, disabling Gemini’s lock screen access entirely is your safest bet until the patch arrives.