Enlarge (credit: Xplora )

A popular smartwatch designed exclusively for children contains an undocumented backdoor that makes it possible for someone to remotely capture camera snapshots, wiretap voice calls, and track locations in real time, a researcher said.

The X4 smartwatch is marketed by Xplora, a Norway-based seller of children’s watches. The device, which sells for about $200, runs on Android and offers a range of capabilities, including the ability to make and receive voice calls to parent-approved numbers and to send an SOS broadcast that alerts emergency contacts to the location of the watch. A separate app that runs on the smartphones of parents allows them to control how the watches are used and receive warnings when a child has strayed beyond a present geographic boundary.

But that’s not all

It turns out that the X4 contains something else: a backdoor that went undiscovered until some impressive digital sleuthing. The backdoor is activated by sending an encrypted text message. Harrison Sand, a researcher at Norwegian security company Mnemonic, said that commands exist for surreptitiously reporting the watch’s real-time location , taking a snapshot and sending it to an Xplora server, and making a phone call that transmits all sounds within earshot.

With the name Smarter, you might expect a network-connected kitchen appliance maker to be, well, smarter than companies selling conventional appliances. But in the case of the Smarter’s Internet-of-things coffee maker, you’d be wrong.

As a thought experiment, Martin Hron, a researcher at security company Avast, reverse engineered one of the $250 devices to see what kinds of hacks he could do. After just a week of effort, the unqualified answer was: quite a lot. Specifically, he could trigger the coffee maker to turn on the burner, dispense water, spin the bean grinder, and display a ransom message, all while beeping repeatedly. Oh, and by the way, the only way to stop the chaos was to unplug the power cord. Like this:

“It’s possible,” Hron said in an interview. “It was done to point out that this did happen and could happen to other IoT devices. This is a good example of an out-of-the-box problem. You don't have to configure anything. Usually, the vendors don’t think about this.”