Tyler Lizenby / CNET

Google's Nest Secure hub, the Nest Guard, had a microphone, but you wouldn't have known that from the specs or the company itself.

That became apparent after Feb. 4, when Google announced that its voice assistant would be coming to Nest Secure. The microphone has never been listed on Nest Secure's technical specifications, and was not publicized from Google.

In a statement first reported by Business Insider, Google said the omission was a mistake.

"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. The microphone has never been on and is only activated when users specifically enable the option," a Google spokesperson said in an email to CNET.

The spokesperson added that Nest Secure had the microphone for future features like detecting the sound of glass breaking.

Nest Secure is Nest's $399 home security system. Like the Ring Alarm Security Kit, Abode and SimpliSafe, Nest Secure is a user-installable home security system that includes a hub and a handful of sensor accessories. Nest announced in February that the Guard hub has built-in Google Assistant voice capabilities, but the company didn't previously disclose that the Guard hub had an integrated microphone.

The omission will strike some people as a privacy concern, given that the microphone has been on Nest's home security hub since 2017. Google has also been in hot water over privacy issues, for instance facing a $57 million fine in Europe for violating the European Union's General Data Protection Regulation.

Nest has suffered other privacy controversies recently. Last month, a hacker infiltrated the Nest Cam security camera of a San Francisco Bay Area family by using a password obtained from a third-party breach. The hacker convinced the family that the US was under nuclear attack from North Korea. In December, another hacker took over the camera of a man in Arizona to warn him of security vulnerabilities. In another case that month, a hacker told a couple through the device that he'd kidnap their child.

While Nest's systems weren't breached in any of those incidents, they raised concerns for consumers. Last month, Nest's general manager Rishi Chandra sent an email to customers reminding them of good cybersecurity habits.

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Google bought Nest for $3 billion in 2014. The startup, which largely brought smart home devices into the mainstream with its web-connected thermostat, was co-founded by former Apple hardware czar Tony Fadell. After Google restructured itself under its parent company, Alphabet, a year later, Nest became a semi-independent division within the conglomerate. But Nest rejoined Google last year as the search company was making a bigger push in smart home products.

Aside from its Nest devices, Google also makes the Home smart speaker, Home Hub smart display and Google WiFi mesh router.



Google has been slammed for its location data-tracking practices, along with allowing third-party developers to read people's emails on Gmail.

Last September, Google's chief privacy officer, Keith Enright, told the Senate Commerce Committee that the company has made mistakes on privacy issues. The hidden microphone is Google's latest error in privacy.

CNET's Richard Nieva contributed to this report.

Correction: This story originally misstated the location of the microphone. It's on Nest Secure's home security hub.

Originally published at 7:15 a.m. PT.

Updated at 7:34 a.m. PT: Adds details on privacy issues and Google; 8:43 a.m. PT: Adds details about Nest Secure; and 10:46 a.m. PT: Adds more background.