Red Star Linux Adds Secret Watermarks To Files

An anonymous reader writes: ERNW security analyst Florian Grunow says that North Korea's Red Star Linux operating system is tracking users by tagging content with unique hidden tags. He particularizes that files including Word documents and JPEG images connected to but not necessarily executed in Red Star will have a tag introduced into its code that includes a number based on hardware serial numbers. Red Star's development team seems to have created some quite interesting custom additions to Linux kernel and userspace, based on which Grunow has written a technical analysis.