FreeBSD Security Advisory FreeBSD-SA-14:31.ntp

[Garrett Wollman]

<<On Wed, 24 Dec 2014 17:12:04 +0000, Glen Barber <gjb at FreeBSD.org> said:

> On Wed, Dec 24, 2014 at 05:42:16PM +0100, Andrei wrote:
>> On Wed, 24 Dec 2014 00:33:09 +0100 (CET)
>> FreeBSD Security Advisories <security-advisories at freebsd.org> wrote:
>> > ports, namely tcp/123 and udp/123 when it is not clear that all
>> > systems have been patched or have ntpd(8) stopped.
>> 
>> Why tcp/123?
>> 

>  gjb at nucleus:~ % grep -i ^ntp /etc/services
>  ntp             123/tcp    #Network Time Protocol
>  ntp             123/udp    #Network Time Protocol

It's IANA's policy to reserve the ports for both TCP and UDP.  NTP
does not use TCP, nor has it ever done so.  It's highly unlikely that
it ever will.  You might as well tell people to firewall 123/sctp as
well; it will have just as much effect.

-GAWollman