The 31-year-old striker scored 26 goals in 58 games for Albion, before going on to win the Premier League title with Leicester.
He has struggled for game time at the Foxes recently and there has been speculation he is close to returning to the Seagulls on loan.
Asked if Brighton are trying to get Ulloa back, Hughton said after this afternoon's 1-0 FA Cup victory at Middlesbrough: "There's nothing I can tell you. We are trying to make sure we have the best squad we can by the time this window closes.
"We are working as hard as we can and certainly if we make any additions, then you will know once any business is done.
"But one thing I will reiterate is I am happy with the squad I've got. For the large part of the season so far, we've fared quite well. If we do (sign any more players), we do. If we don't, I'm very happy with the squad."