that is not incorrect and it is not manipulation either.
it simply is an average price that a couple of hundred exchanges report. so it will always have a certain percentage difference from any exchange that you look at. higher than some and lower than others. next time when you visited CMC check out the "Markets" tab and see how many values they are using to get to that average.

for example the current price in BTC/USD markets listed on CMC are in the range from $8,599.84 down to $8,201.80 so the average reported price in this site is $8,309.94 while Bitstamp price is $8,292 Bitfinex is $8,311 Kraken is $8,288,...