Sunderland goalkeeper Jordan Pickford has been ruled out for up to eight weeks with a cruciate ligament strain.
Pickford hurt his knee in a collision with Papy Djilobodji as Zlatan Ibrahimovic scored Manchester United's second goal in a 3-1 Premier League defeat on Boxing Day.
"Jordan Pickford has good news and bad news," Moyes told a news conference.
"The good news is he hasn't ruptured his ACL, the bad news is he's strained it.
"We're looking at six to eight weeks, it's a major disappointment for him and for us because he's been saving us points."
"Vito is fine and he's been training for many weeks since his injury. He has a lot of experience," he added.
Providing fitness updates on the rest of his squad, Moyes commented: "Jack Rodwell is back in training and Javier Manquillo and Steven Pienaar have also been involved."
