Skrine signed with the 49ers on Tuesday, David Lombardi of The Athletic reports.
Injuries are stacking up in the 49ers' secondary. Jason Verrett tore his ACL in Week 1. K'Waun Williams (calf) is expected to miss a few weeks. And Josh Norman is dealing with a lung contusion. Skrine, 32, averaged 46.3 defensive snaps across 12 games for the Bears last season, so he'll add dependable depth while the Niners heal.