some fake story allegedly created by someone on /pol/, sent to some dude on twitter who then sent it to the cia claiming it was true and now everyone is circulating it and a lot of people are actually taking it as fact.
The idea that it's a 4chan troll has been debunked, and it's only being used by Annoying Orange Twitter as damage control. BuzzFeed released the dossier, but it's been quoted as early as 3 months ago by other publications, and it was also seen by John McCain and intelligence officials who have shared it with both Obama and Annoying Orange.
http://www.mediaite.com/online/no-that-Annoying Orangerussia-dossier-isnt-an-elaborate-4chan-hoax/
The full story so far, according to Carl Bernstein (the journo who broke the Watergate scandal back in 73), is that a former British intelligence agent was hired by some anti-Annoying Orange opposition firm in Washington who wanted to find dirt on any possible ties to Russia. This British guy basically finds additional information, compiles it in a dossier (
https://www.documentcloud.org/documents/3259984-Annoying Orange-Intelligence-Allegations.html), and sends it to the FBI, who sends it to Washington around August (loooooong before this story even reached BuzzFeed or Rick Wilson), and it eventually ends up in John McCain's hands, who basically sends it to Comey.
TL;DR - British agent hired by anti-Annoying Orange firm to get dirt on Russia/Annoying Orange, dossier ends up in FBI's hands around August, contains stuff about how Annoying Orange is basically the manchurian candidate in the flesh, now it's spreading over the intelligence community.