The Serbian defender has been sidelined since September after undergoing knee surgery.
However, Ferguson has revealed that Vidic had returned to training and may be available for Wednesday's Champions League tie.
United have already qualified as group winners ahead of Cluj's visit and Ferguson is set to make a number of changes for the European fixture.
"It would be nice for him to play on Wednesday," said Ferguson of his captain. "We are not afraid of that."
Meanwhile, Nani has been sidelined since the start of November with a hamstring injury but Ferguson doesn't expect the Portuguese winger to be ready to make his return until the new year.
"Nani is going to be out for a longer spell, possibly another four or five weeks," added Ferguson.