DPRK seems to know a LOT more than HTML. They are not dependent on (read vulnerable to) the Internet in the burgeoning ways of the rest of the world. They clearly see it asymmetrically, as our Kryptonite:
This doesn't tell me they know what they're doing. This tells me they are scrambling for a few million here and there when they can. Wouldn't you guess that a state funded actor could be much more dangerous than encrypting your personal files and demanding $400 while leaving a kill switch easily available?
1) "its connection to a hacking group called Lazarus that is linked to last year’s $81 million cyber heist at the Bangladesh central bank and the 2014 attack on Sony’s Hollywood studio" - https://www.reuters.com/article/us-cyber-northkorea-exclusiv...
2) "Bureau 121 is staffed by some of North Korea's most talented computer experts and is run by the Korean military." - https://en.wikipedia.org/wiki/Bureau_121#cite_note-reuters-1
3) "The wannacry ransomware has a link to suspected North Korean hackers" - https://www.wired.com/2017/05/wannacry-ransomware-link-suspe...