Moses picked up the injury during the defeat to Burnley last weekend. He is currently on loan at the Britannia Stadium.
Moses sustained the injury during the 2-1 defeat to Burnley on Saturday and has been ruled out for up to eight weeks.
Hughes is sweating on the fitness of Asmir Begovic, Phil Bardlsey and Geoff Cameron after they were all sent home because of illness that has struck the club this week, and the Potters' boss is hopeful it is only a short-term illness.
He told reporters: "It could be the time of the year we are in, I don't know. Maybe it could have been picked up from youngsters. We're hoping that it's just a 24-hour thing."
There is, however, good news on the injury front for his side with Marc Wilson returning to full training and defender Robert Huth edging closer to full fitness.
Hughes will be looking for his player to take their third significant scalp of the season on the road having beaten Manchester City and Tottenham already in the Premier League this season, and the Welshman admitted the side relishes games against the more prolific opponents. They will be facing a Liverpool side that hasn't won in their last five matches and are struggling for form.
He said: "We've been organised and difficult to break down but have had a threat on the break. We've had success with that on our travels with that. Maybe it has been a little bit easier in some ways away from home.
"Fatigue can effect Liverpool with Champions League matches having an impact but they have a big squad and you see they have plenty of resources on the bench and in the squad. Maybe there is added focus on them at the moment though and if we can add to that then we will do. They are an outstanding team though and we won't take them lightly."