USA is really good at spinning stories.

https://sg.news.yahoo.com/exclusive-north-koreas-unit-180-cyber-warfare-cell-030700681.html

USA has claimed that wannacry ransomware is executed by NK which operates from a China base so that it won't be traced back to NK.  USA has been accusing China for a long time already but this time has shifted the blame to NK.

China can shift the blame to NK for future hackings now because USA has officially declared that NK operates in China.  This is definitely a good excuse for China.