Always-on listening devices were popularised with the first Moto X back in 2013. Saying “Ok Google Now” could wake the phone up even from standby, because dedicated hardware was constantly listening to ambient sounds to pick up that catchphrase. We’ve come a long way since then, and today you have dedicated voice assistants like Google Home and Amazon Echo, that can be activated hands-free, by simply saying the hotword “Ok Google” or “Alexa” respectively. Now however, researchers claim they can use hidden voice commands to access the assistants.
The Atlantic reported about researchers from the UC Berkley and Georgetown University, who claim they were successful at waking up such devices using sounds that might come across as garbled noises to you.
The video above shows how a smartphone kept many feet away could pick up garbled noises that sound like something out of a horror movie, and perform actions like opening a website or switching the phone to airplane mode. Although you have to listen closely to try and decipher those noises, they’re deliberately designed such that a voice recognition system would be able to clearly understand the command. In the demo, the smartphone was also able to pick up commands with background noises too.
It is fair to note that for long, the Google Now app has had something called ‘Trusted Voice’, where your voice samples are used to identify if it’s the owner saying “Ok Google”. But turning on this feature gives a warning saying, “This can be less secure: a similar voice or recording of yours could unlock your device”. Suffice to say that it’s not a reliable authentication mechanism unlike say, the fingerprint scanner on your phone.
There have been instances in the past where where many Amazon Echos ordered dollhouses for their owners by simply listening to a command playing on TV. Our phones may also be listening to ultrasonic sounds for better ad tracking. It just goes to show that the always-on, voice activated assistants still have a long way to go, until we can trust them to do critical things like making payments or controlling doors at our home.