Package maintainers are aware of security issues. This leads to many "secure by default" service installations which could impose certain restrictions on their normal use. Debian does, however, try to balance security and ease of administration - the programs are not de-activated when you install them (as it is the case with say, the BSD family of operating systems). In any case, prominent security issues (such as
setuid
programs) are part of the
http://www.debian.org/doc/debian-policy/.