Google mistakenly forgot to tell users that Nest Secure comes with built-in microphone

Google's revelation earlier this month that Google Assistant could be used with its Nest home security and alarm system security was a surprise.

Why? Because the Nest Guard alarm/motion sensor/keypad never listed a built-in microphone.

Now, Google has admitted it mistakenly did not list a microphone as part of the product's tech specifications. Its updated product page now mentions one.

"The on-device microphone was never intended to be a secret and should have been listed in the tech specs. That was an error on our part," Google said in a statement to USA Today.

"The microphone has never been on and is only activated when users specifically enable the option," the company's statement continued. "Security systems often use microphones to provide features that rely on sound sensing. We included the mic on the device so that we can potentially offer additional features to our users in the future, such as the ability to detect broken glass."

Google's admission, first reported by Business Insider, comes as consumers increasingly find their privacy being encroached upon by technology. Last month, Apple said a FaceTime bug let users eavesdrop on conversations even if they didn't answer a group chat request. And Facebook is still reeling from the Cambridge Analytica scandal in which the personal data of an estimated 87 million Americans were exposed to manipulation for political purposes during the 2016 election.

Google's Nest has not dodged concerns either. Last week, some Nest security system users got emails requiring them to update their passwords and suggesting they turn on two-factor authentication after reports of hackers taking over home security cameras—and scaring one family with a fake alert about an impending North Korea nuclear attack.

Google, which acquired Nest for $3.2 billion in 2014, announced the Google Assistant update for the Nest Guard product in a blog post two weeks ago. The update would let users arm their system with their voice and also control other products such as a Nest Thermostat and door locks.

"The Google Assistant on Nest Guard is an opt-in feature, and as the feature becomes available to our users, they'll receive an email with instructions on how to enable the feature and turn on the microphone in the Nest app," the company said. "Nest Guard does have one on-device microphone that is not enabled by default."

Security and privacy experts voiced concerns about Google's pronouncement at the time. Nest system users had been able to use Google Assistant but needed a separate Google Assistant-ready device to hear commands, security site CSO noted at the time. "I suppose it depends upon your outlook on if you are happy or creeped out that your security system secretly had an undocumented microphone capable of doing the listening all along," it said.

This isn't the first time Google has faced criticism. In August, the Associated Press reported that apps such as Google Maps will save time-stamped location data even with the location history turned off.

The Electronic Frontier Foundation, a nonprofit digital rights group, offered its take about the Nest development on Twitter on Wednesday: "No product should ever come with a secret microphone, regardless of whether or not it's enabled. That's just bad security design."