North Korea’s surveillance extends beyond its streets and, turns out, even into its custom-built fledgling operating system, dubbed Red Star OS. According to Reuters, which spoke with security experts who had a rare chance to dive deeper into the new operating system, Red Star OS marks each individual file so that North Korea knows who viewed it, and where it came from.

Talk about privacy invasion, right?

The goal, it seems, is to keep the operating system completely locked down and from preventing anyone, even the end user, from tweaking settings that are intended to be active at all times, like the firewall, ERNW GmbH security researchers Florian Grunow and Niklaus Schiess explained to Reuters. Ultimately, though, that means the operating system also “watermarks” each file, even files that haven’t been opened, allowing North Korea to know where files have originated, and who has viewed potentially – but likely not always – illegal documents.

“It’s definitely privacy invading, it’s not transparent to the user,” Grunow told Reuters. “It’s done stealthily, and touches files you haven’t even opened.” Oddly enough, however, there seems to be two sides to this coin.

Grunow and Schiess noted the obvious negatives that come with this sort of surveillance of perhaps unsuspecting North Koreans. Can you imagine if, for example, the White House marked every single file on your computer? Was able to always know which files you created, and which ones passed through your machine? It’s kind of scary to think about.

The good news? The researchers also explained that the severe limitations of the operating system suggest that North Korea hasn’t been behind the high-profile attacks on U.S. computer systems after all. That would be under the assumption they used Red Star OS, however.