buying home with un permitted room addition

[Lenin Belangonda]

Hi, I am buying a home in southern california. This home has a bonus room that was converted into two bedrooms by constructing a wall in the middle with a door. There is no permit and also building codes were not considered. This is stated in the sellers disclosure which was not sent to me by my agent (by mistake). When i am asked to sign the disclosure i noticed this but i have release all contingencies alreaday and only few days left for the escrow closure. Is it ok to keep the unpermitted room as is. Is it still considered illegal if found even though i didnt make that construction. Appreiate any expert advice on this, thx.