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The CID is considering the possibility that this is a deliberate operation by malicious actors -- criminals, terrorists, or state entities hostile to the U.S. -- to gain access to troops' personal data. It is also possible, according to the press release, that these episodes are what is known as "brushing" -- when a company sends products, often counterfeited, to users in hopes that they will offer the company positive user reviews online.

"It's almost always advisable to avoid pairing a personal device to something you cannot accurately confirm the authenticity of," said Joseph Corsi, an Army veteran and chief security officer for Foundry, a Digital Currency Group company. "That could be finding a USB in a parking lot (a popular attack used in the past) or connecting to Wi-Fi that may be maliciously impersonating something like a hotel or airport public network."

The strange smartwatches have arrived at a moment when the services are looking at ways to integrate smart and wearable technology into troops' professional lives. Increasingly, these devices offer opportunities to measure health and fitness, and help troops train toward goals.

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The military learned a lot about how to integrate wearable devices into readiness during the COVID-19 pandemic. A program run by the Defense Innovation Unit called the Rapid Assessment of Threat Exposure, or RATE, hopes to track service members' health and better predict and track dangerous infections. The Pentagon said the program received $10 million in funding in May. And the Space Force is in the process of rolling out a program that uses wearable fitness devices such as smartwatches to help gauge progress among its members.

"If it seems too good to be true, it probably is," Corsi said. "Toss strange or unsolicited equipment in the garbage and go on with your day. Maybe check with your spouse first, though."