Allegri knows the experienced forward well, having previously coached him during their time at Milan.
Since his departure from Milan, the 32-year-old has turned out for both Inter and Parma, but he left the latter on Monday by mutual consent.
A 2-1 defeat to Cesena left Parma bottom of the table with just nine points, while they have also received a one-point deduction for unpaid player wages.
Now a free agent, Cassano has been linked with a number of clubs, and Allegri was coy when quizzed about bringing him to Juve.
"I don't talk about players from other teams, although at the moment Cassano is no longer in another team," explained Allegri.
"At the moment we have five strikers in attack, and at the moment no-one else has come in.
"Cassano is a player I coached at Milan, who fortunately was crucial in the Scudetto race.
"He's a player who has great quality on a technical level.
"I only speak about the players I have available, and then those who arrive I'll speak to when they get here.
"We'll see what opportunities there are before doing anything else, but we're alert to that, we don't need to worry and we can just think about the next game, which is tomorrow."
Juventus are the visitors at Cassano's former club Parma in the Coppa Italia quarter-finals on Wednesday.
