Eberflus said the Bears were not sure if Jackson will need surgery to repair the Lisfranc injury.
"We'll have to wait and see when he sees the doctor, but we'll get that squared away," he said.
The Bears placed Jackson, tied for third in the NFL with four interceptions, on injured reserve on Tuesday. He was hurt in the second quarter of Sunday's loss to the New York Jets. Leading receiver Darnell Mooney also suffered a season-ending ankle injury in that game.
Jackson's injury combined with a concussion Jaquan Brisker already had and a hamstring injury to Dane Cruikshank left the Bears playing their only two remaining safeties - DeAndre Houston-Carson and rookie seventh-round pick Elijah Hicks.
The Bears placed Cruikshank on injured reserve on Wednesday and signed quarterback Tim Boyle from Detroit's practice squad to the active roster, with Justin Fields (left shoulder) and Trevor Siemian (strained oblique) hurt. They also signed defensive lineman Andrew Brown to the active roster from Arizona's practice squad.
The Bears (3-9) host rival Green Bay (4-8) on Sunday. The Packers beat them 27-10 at Lambeau Field in Week 2.