In a few days, Real Madrid will play against Real Betis. As guests, of course, they will get an onslaught from the host. If in this match Real Madrid will still concede (especially if many goals are created) then the Real Madrid defense line does need serious attention. The transfer window will also close in a few days, so Real Madrid has very little time if they want to make improvements. Hopefully, there is good news before the transfer window actually closes.
You are right when you say that there is no news yet about new transfers from Real, so there is no chenses of Real Madrid's defensive line renewal.We must also take into account that Betis is not an easy opponent for Real Madrid. The match will be interesting, I think that both teams will score goals, but most likely the bookmakers will give low odds for this event.