So for everyone asking if this report is legit, the answer is that we don't have official corroboration yet on the report details from anyone in the Intelligence community (other than the MI6 agent who produced the report).
HOWEVER, many sources confirmed that this was included in the briefing that Trump got on Friday. For something to be included in that briefing, it would have to be not only thoroughly reviewed by the CIA, but also that they believe a lot of it to be very credible. They simply aren't going to put any shaky evidence in front of the President Elect.