CMC takes into account several prices from different exchanges and then gets an average price so you shouldn't expect the btc price on this site to 100% match with other exchanges. With that in mind, perhaps yesterday one of the exchanges glitched or something else happened which made CMC show a higher price (?).
To be honest, CMC has been accused of manipulating prices and display fake volume several times so i wouldn't be surprised if they messed with something yesterday.
I had read about it, was it true at the end? I don't really see the kind of manipulation that can be done by changing prices on CMC, as long as the real price is the one displayed on the exchange, where the trading is done... Wasn't it just the misunderstanding of some in the functioning of an exchange?