Exum signed a one-year deal with the 49ers on Sunday.
Exum re-signed with the 49ers in March but was released at Saturday's roster cutdowns, only to end up back with the team a day later. The 28-year-old played more defensive snaps in 2018 than he did across his first three seasons and had 40 tackles (34 solo), one sack, one interception and one forced fumble.