You can read about the BuzzFeed story here:

http://www.lifezette.com/polizette/buzzfeed-runs-error-laden-unverifiable-trump-russia-claim/

But it was actually all made up by internet anarchists, as their own whacked-out version of political theater, in late October.

This chart gives the general scheme of the "information" flow:

In the above, the box labelled "Anonymous" represents someone who set up a fake Twitter account pretending to be someone with inside information, who eventually acquired 20,000 followers. Simultaneously this person described what he was doing on the highly anarchic 4chan.org/pol message board. The fake intel report made up by this person eventually made its way to the CIA, who apparently added more made up stuff of their own, and now have leaked it to BuzzFeed.

I hear this fake story may be presented as real in tomorrow's Washington Post. We'll have to wait and see.

Below is a link to a large infographic with more tidbits on how this scam came about:

http://www.rumormillnews.com/pix8/4chan_larp_1.jpg