Re: AD in the DMZ . . . OK?

[Ansgar -59cobalt- Wiechers <bugtraq () planetcobalt net>]

On 2004-08-01 Dieter Sarrazyn wrote:
> On 2004-07-30 Ansgar -59cobalt- Wiechers wrote:
> > On 2004-07-30 Dieter Sarrazyn wrote:
> > > Wouldn't using LDAP be a solution here? Every AD system is in fact
> > > also an ldap server.
> > >
> > > If the only thing needed is authentication with userid/password,
> > > then this is fairly simple to do. A special group could be created
> > > containing all users that are allowed to use this type of
> > > authentication. Using a "ldap-read" user which has only read access
> > > to this group is pretty secure I guess.
> >
> > If I'm reading you correctly that would still require access from the
> > DMZ to the DC, thus still violating the DMZ. No host in the DMZ
> > should ever be able to access any service inside the internal
> > network.
>
> What about your email traffic then?

What about it? Your internal MTA polls the MTA in your DMZ which
receives mail from the outside world.

> The traffic I'm talking about is only a very limited ldap traffic with
> a very restricted user.

I know. However, it doesn't matter how limited the traffic is. The
internal network should not be accessible from the DMZ. Period. Of
course there may be exceptions, but I seriously doubt that a web-
application qualifies as such.

Regards
Ansgar Wiechers
-- 
"Those who would give up liberty for a little temporary safety
deserve neither liberty nor safety, and will lose both."
--Benjamin Franklin

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