Not really. WordPress uses SQL, which, if you take over an SQL server, you can see everything. I say "not really" because yes, there is always a possibility.
I've personally been using WP for several years and haven't had a problem with security, but I stay up to date on the versions. Secure passwords and a secure server are your biggest issues.
Besides, I don't think you want to dig through the code to do a search/replace of table names. Talk about a huge amount of work to be overwritten on the next upgrade.