Pagano, 58, was the Colts' coach from 2012-2017. He previously served as the defensive coordinator for the Baltimore Ravens and has been a defensive assistant since the 1980s at both the pro and collegiate level.
The Bears interviewed defensive backs coach Ed Donatell on Thursday for the position. Donatell has been with the organization since 2015.
Pagano was out of football during the 2018 season but is a sought-after candidate for a number of openings. Bob McManaman of the Arizona Republic reported the Cardinals and Browns both have interest in Pagano for their defensive coordinator position.
It would make some level of sense for the Bears to promote internally. Chicago led the NFL with 27 interceptions and held opposing quarterbacks to a quarterback rating of just 72.9. Donatell in many senses has earned the job, and it's possible he'll get a look for some other defensive openings when top picks start coming off the board.
Pagano, meanwhile, seemingly will have his pick of job offers. The Bears offer the most talented defense, and as Fangio proved, the easiest route to returning to a head coaching spot.