According to police, around 1:00 a.m. a vehicle was traveling northbound at the 79th Street exit of the highway when someone in another car fired shots.
Both victims were transported to the University of Chicago Medical Center with non-life threatening injuries, ISP said.
Troopers initially had part of the highway shut down while they investigated but all lanes have since reopened.
No one is in custody, ISP said.
No other injuries were reported.
Illinois State Police are investigating.