The local currency had closed at 397/dollar on Tuesday.
At the interbank market, the naira closed at 315.93/dollar, lower than 305.5 it recorded on Tuesday.
The naira, which hit a fresh record low since the CBN floated the currency on the official interbank market in June, first touched 400/dollar at the black market this month.
On the interbank market on Wednesday, no trades were posted until three minutes before the end of the session, when the CBN which has been reducing its dollar sales, intervened, Reuters reports.
Only three deals worth $0.75m were traded at 305.50 per dollar, a level the market has closed at since Monday. Also, the naira had hit an all-time low of 365.25 per dollar on the interbank on Thursday.