After a goalless draw at the Stadium of Light in the fourth round, the two sides go head-to-head again to earn the right to take on Chelsea's conquerors Bradford City.
When Symons replaced Felix Magath in mid-September Fulham only had one point from seven matches, but the former Wales international has secured a further 33 points to move the club away from danger.
One of their many impressive performances under Symons came in the first meeting with Sunderland when they almost caused an upset.
McCormack was guilty of spurning a couple of presentable chances to win that game, while Colombian team-mate Hugo Rodallega struck the post in stoppage time
And the former Leeds United striker believes the newfound confidence within the club can help them pick up a Premier League scalp.
"It's a good chance at Craven Cottage, where we've proven we can beat anyone – we can blow teams away and we'll definitely be looking to do that," he told the club's official website.
"I've heard a lot of people say that we should have beaten Sunderland at their place, but if you look at the game they had quite a few chances.
"Betts [goalkeeper Marcus Bettinelli] probably kept us in the game so I think a draw was a fair result in the end. If we were given that before the game, a clean sheet against a Premier League team and taking them back to the Cottage, I think we might have taken that."
The result was less impressive for Sunderland and they will be desperate to make the fifth round for the third time in four seasons.
Gus Poyet's side failed to win for the 12th time at home in all competitions this season, but they quickly recovered with a vital 2-0 Premier League triumph over Burnley on Saturday.
Victory included Jermain Defoe's first Sunderland goal following his move from Toronto FC earlier this month, and he is eager to add to his tally in the Cup.
"It's a massive game, especially when you look at who we could get after if we progress," he told Sunderland's official website. "You never know what can happen, especially in the FA Cup, I'm looking forward to that one.
"On the back of a win everyone will be confident going into the game. Hopefully we can go there, relax and play. I'm sure we'll create chances and I believe that we're good enough to win the game."
Poyet will be able to recall Jack Rodwell for the trip to London after he served his one-match suspension last weekend, having been sent off in the first game.
However, Lee Cattermole and Wes Brown remain doubtful as they recover from knee injuries.
