Re: Is FreeBSD susceptible to this vulnerability?

From: Jacques A. Vidrine (nectar@FreeBSD.ORG)
Date: 03/28/02 

Date: Thu, 28 Mar 2002 09:03:25 -0600
From: "Jacques A. Vidrine" <nectar@FreeBSD.ORG>
To: Brett Glass <brett@lariat.org>

On Thu, Mar 28, 2002 at 07:31:03AM -0700, Brett Glass wrote:
> Apparently, several UNIX-like operating systems can be penetrated via
> XDMCP/UDP; see
>
> http://www.procheckup.com/security_info/vuln_pr0208.html
>
> Is FreeBSD vulnerable? What about the other BSDs?

No, and this isn't exactly a `vulnerability'. It is an insecure
default configuration. This ``advisory'' is mostly a marketing ploy
for this ProCheckUp tool.

This is ancient issue. I really don't get their `Comment' --- this
has been an administration issue since XDMCP existed (decades). You
can find your `Xaccess' file in /etc/X11/xdm/Xaccess or
/usr/X11R6/lib/X11/xdm/Xaccess. By default, XFree86 does not allow
remote hosts.

Of course, this only applies if you are running xdm. You have to turn
xdm on yourself --- it is not on by default.

Note that wdm, gdm, and kdm have their own Xaccess files (IIRC), and
these have to be checked also if you are running them (duh).

Cheers, 

-- 
Jacques A. Vidrine <n@nectar.cc>                 http://www.nectar.cc/
NTT/Verio SME          .     FreeBSD UNIX     .       Heimdal Kerberos
jvidrine@verio.net     .  nectar@FreeBSD.org  .          nectar@kth.se
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