No, there is no default certificate store. There is a README file under
/usr/src/crypto/openssl/certs, that states that
The OpenSSL project does not (any longer) include root CA certificates.
Please check out the FAQ:
* How can I set up a bundle of commercial root CA certificates?
The FAQ in question can be found here, and basically says that the OpenSSL project doesn't have a policy on what CAs to include or exclude. Installing the
security/ca_root_nss port is the best thing to do, if you need a CA store. Indeed, many ports depend on it, so it's probably installed on a high proportion of FreeBSD systems.