All perfect praise be to Allah, the Lord of the Worlds; may His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
If you get a job in a Riba-based bank and that job doesn`t directly deal with Riba (Usury/interest)-a security guard or chief of personnel-then We (Iftaa` Department) pray that Allah doesn`t hold you accountable for that because such a job doesn`t directly help in Riba-based transactions.
Moreover, the Central Bank is the state`s treasury and deals with Riba. If your work in this institution involves dealing with Riba directly, then We hope that Allah doesn`t hold you liable for that, but We recommend that you look for another job to avoid this suspicious line of work. And Allah The Almighty Knows Best.