That may not sound like a big deal. But imagine thousands or even hundreds of thousands of internet-connected devices in close proximity. Malware created by hackers could be spread like a pathogen among the devices by compromising just one of them.

And they wouldn’t have to have direct access to the devices to infect them: The researchers were able to spread infection in a network inside a building by driving a car 229 feet away.

Just two weeks ago, hackers briefly denied access to whole chunks of the internet by creating a flood of traffic that overwhelmed the servers of a New Hampshire company called Dyn, which helps manage key components of the internet.

Security experts say they believe the hackers found the horsepower necessary for their attack by taking control of a range of internet-connected devices, but the hackers did not use the method detailed in the report being made public Thursday. One Chinese wireless camera manufacturer said weak passwords on some of its products were partly to blame for the attack.

Though it was not the first time hackers used the Internet of Things to power an attack, the scale of the effort against Dyn was a revelation to people who didn’t realize that having internet-connected things knitted into daily life would come with new risks.