New boss Claude Puel is planning a New Year shake-up and Musa, who cost £16.6m, and Ulloa, £8m, are thought to top his exit list. Super Eagles winger Musa was signed from CSKA Moscow in July, 2016.
He has made just 14 starts and 19 appearances on the bench for the Foxes, scoring four times.
Yohan Benalouane, who cost £5m, is also in line for the chop.
The three players have not played a minute of Premier League football so far this season under Craig Shakespeare and Puel.
He said, “Some players for the moment are starting players, on the bench, or cannot play, but for these games they can have some opportunities to play.
“So it’s important to keep them with a positive attitude, strong and with hard work on the pitch.
“And for this moment they are professional and very concentrated about training sessions.
“They also play sometimes with the U23s to keep a good level. That is very important.
“After the games in November and December, we will see in the window of course, with game time for every player whether it’s enough and not enough, and we will see what we can do with different players.
“But with the moment I am happy with the hard work of the team.”