The number one seed required one hour and 36 minutes to defeat the American 4-6 6-3 6-1 at the ATP 250 hard-court event on Thursday.
Ferrer - who was handed a bye in the first round - surrendered serve in just the fourth game of the opening set to trail 3-1 and although he eventually broke back, Sock was still good enough to take the first set.
It was a formality from there, however, with the American winning just four of the next 16 games, as Ferrer set up a quarter-final tie with fellow Spaniard Fernando Verdasco.
Verdasco hit seven aces as he overcame three-time finalist Jarkko Nieminen of Finland 6-2 3-6 6-3.
The winner showed plenty of resistance throughout the match, fending off eight of the 11 break points he faced.
Second seed Milos Raonic will face Benoit Paire in the last eight, after he knocked out qualifier Joachim Johansson.
The Canadian required one hour and 23 minutes to dispatch of the Swede 6-2 7-6 (7-3).
Fellow seeds Ernests Gulbis (fifth) and Grigor Dimitrov (seventh) also booked their spot in the quarter finals.
Latvian Gulbis - who has won two tour titles this season - saw off the challenge of Dutchman Igor Sijsling with a 6-3 7-6 (7-3) triumph, while Bulgarian Dimitrov had too much quality for German Jan-Lennard Struff and secured a comfortable 6-1 6-3 success.
There was a shock for fourth seed Kevin Anderson of South Africa, however, as he was ousted by world number 96 Kenny de Schepper.
The Frenchman was victorious in a close match, eventually earning a 7-6 (7-5) 4-6 6-3 victory in two hours and 13 minutes.