Buzzfeed doesn't so much "make up" their stories as publish whatever rumors they hear as "news" before they are validated.
they do virtually no research on their own - just run with what they hear in an effort to be the ones to "scoop".
This is because after years and years of trying to be a news agency - they are still really just the "what disney princess are you?" quiz site.
…making them really susceptible to leaks, planted or not.
MSM then "picks up" their "news" and runs with it if it looks bad for the other side (us) - mostly without verifying reports.