well ssh isnt part of the DA package system which is why it has no knowledge base entry. It will be dependent on your os.
For FreeBSD ssh is shipped with the os but they probably wont patch it until a newer version is out (5.5 or 6.0) if they consider it serious enough it may get a advisory and they will patch it that way.
So the easier and faster way is to install the openssh-portable port by doing the following and this assumes you have cvsup installed, portupgrade and a up to date ports repository.
cd /usr/ports/security/openssh-portable
make install clean
/etc/rc.d/sshd stop
nano /etc/rc.conf
edit sshd_program="/usr/local/sbin/sshd"
/etc/rc.d/sshd start
if you already have the port installed then a simple portupgrade will upgrade it for you, then you just restart the daemon after.
Few notes.
DA wont append the config unless you specify the new location in directadmin.conf.
If you dont reorder the path or remove the base version of the binaries then running commands such as scp or ssh will run the older versions, unless you specify full path.
The new config location is /usr/local/etc/ssh/sshd_config so make sure it is correct before using it.