This winter, Jeffrey Bigham, a computer science professor at Carnegie Mellon University, rented an Airbnb with his family. During the stay he noticed something weird: two white objects hiding in plain sight in the rental’s rooms. It was a security camera, which Bigham found unsettling. “I was shocked, and immediately unplugged them,” he wrote in a blog post yesterday.

It seems like a pretty blatant invasion of privacy. Bigham admits that the rental property told him there were cameras “at the entrance,” which is not the location of either of the ones he found. And when he reported his findings to Airbnb, the platform said the hosts properly disclosed the camera because of a picture in the listing. The picture shows one of the rooms with the camera. In the foreground is a couch and a TV, along with three oddly placed pictures on the wall in the background. If you squint your eyes and look to the left corner, you can see a white object. It’s not obviously a camera. Yet Bigham says that’s what Airbnb considered proper disclosure. (Update: see below.)

Bigham’s experience is indicative of a growing problem on Airbnb. More hosts are surreptitiously recording guests–likely as a defense in case crazy stuff happens. Sometimes we hear of egregious examples, where guests were able to get Airbnb’s attention because they discovered a hidden camera in a place like a bathroom. But during these less outrageous situations–which are invasions of privacy, nonetheless–Airbnb users have less recourse.

“I feel like our experience is in some ways more insidious,” writes Bigham. “If you find a truly hidden camera in your bedroom or bathroom, AirBnB will support you. If you find an undisclosed camera in the private living room, AirBnB will not support you.”

For now, Bigham can find solace in the fact that he wrote something that’s shedding light on the issue. We’ll see if this saga hurts his Airbnb standing; the host left him a bad review for unplugging the camera.

You can read Bigham’s full post here.

Update: Airbnb tells me it now has given Bigham a refund. A spokesperson provided me with the following statement: