How many would you consider acceptable to have an international banking system? North Korea hackers stole $81 million from the Bangladesh central bank, and it was only a fluke that they didn't get away with over a billion from that one hack.

https://www.bbc.com/news/stories-57520169

More prosaic wire fraud is common in real estate and B2B transactions, and if not noticed immediately the funds are often lost after being transferred internationally and cashed out. It wouldn't be surprising if NK is behind some of that, given what they managed against Bangladesh.