According to Ian Rapoport the 49ers will activate DB Eric Wright from the NFI List and release DB Nnamdi Asomugha to make room for Wright.
#49ers will have several moves today, including cutting Nnamdi, activating Eric Wright, and almost certainly activating Mario Manningham.
— Ian Rapoport (@RapSheet) November 4, 2013
In the offseason the 49ers had a trade in place for Wright, but he failed his physical which voided that trade. After the Buccaneers released Wright the 49ers signed him and placed him on the NFI List.
Nnamdi was signed in the offseason on a one year deal and he saw action in 3 games where he recorded two tackles and two passes defensed. Nnamdi was expendable due to the play of DB Tramaine Brock.