Red Star OS is based on a Linux 2009 version called Fedora 11. It has its own firewall, antivirus system and web browser point to internal North Korean servers. OS is designed to crack down on the growing illegal exchange of foreign media content, including films, music or document files. OS monitors the computer for any changes made to the system files and monitors every move of a user. OS has no sign in the OS of cyber attack capability North Korea has been accused of, although visitors to North Korea say most computers still use Windows XP.
Source: https://thehackernews.com/2015/12/north-korea-red-star-os.html