No one knows quite what to make of this. Maybe the Norks have gotten wind of an actual, honest-to-goodness CIA plot. Perhaps someone in the North Korean government wants Kim Jong Un gone, so they're offering the CIA helpful suggestions about how to do the deed. It's also possible that they finally got around to screening "The Interview" and they're under the mistaken impression that it's documentary.
All we really know is that Pyongyang is accusing the CIA of planning the assassination of Kim Jong Un, and they're weirdly specific about the methods that are going to come into play.