Ports collection prior to the correction date.
FreeBSD 3.x, were named xntpd.
building of a response for a query with a large readvar argument.
problem since it was corrected before the release.
ntpd server as the user running the ntpd daemon, usually root.
ntpd, your system is not vulnerable.
The following patch applies to FreeBSD 4.x.
The folllowing patch applies to FreeBSD 3.x.
kill and restart the ntpd daemon if it is already running.
1) Upgrade your entire ports collection and rebuild the ntpd port.