It has a cored deck, as do the vast majority of boats. BUT... The coring usually stops inboard of the toerail and the stanchions and toerail (which holds the boat together) are almost always mounted on solid fibreglass. In the case of a stanchion base with three screws, the inboard screw sometimes does pierce the core.
The crazing that you see at the stanchion bases is normal and not something to worry about too much. A surveyor can tell you what's going on there.
The link below will take you to a website that has vast amounts of information on C & C's:
C&C Yachts - C&C Photo Album & Resource Center