Chrome OS will Block USBs on Lock Screen, But You Can Whitelist Devices

Remember this post about an upcoming Chrome OS feature that will block new USB devices on the lock screen? Looks like you will have an option to add trusted devices to a whitelist.

Update: The latest Chrome OS Canary version has this flag:

Block new USB devices at the lock screen.

Prevents newly connected USB devices from operating at the lock screen until Chrome OS is unlocked to protect against malicious USB devices. Already connected USB devices will continue to function. – Chrome OS

USBGuard

Internal code calls this feature USBGuard. I can see a new internal flag right next to the “Enable USBGuard at the on Chrome OS” flag in the code.

The new flag is explained thus:

Enable USB Bouncer for managing a device whitelist for USBGuard on Chrome OS

Here is the commit log that explains this feature further:

Add USB Bouncer feature flag for Chrome OS.

This adds the USB Bouncer feature flag that controls whether or not a
user specific USB device whitelist will be used for generating the
policy for USB Guard.

Based on this limited information that is available to us, this is how I think this will work. You will have an option to disable USB devices on the Chrome OS lock screen. If we opt-in for this, there will also be an option to whitelist our existing devices. For example, keyboard and mice.

That’s all we have for now. I am sure we will see this new feature in action soon. Stay tuned for more updates!