Full back Sidibe limped out of Sunday's training session with an ankle injury a day after France beat Argentina 4-3 in the last 16.
"It's nothing serious. I can't say he'll train with the others today and his ankle is bruised but it's nothing big," Stephan told a news conference on Monday.
He added that full back Lucas Hernandez was nursing a minor muscle problem.
Another full back, Benjamin Mendy, had suffered a thigh muscle problem but "he will resume his activity today", said Stephan.
(Reporting by Julien Pretot; Editing by Amlan Chakraborty)
