Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 24 Jul 2001 19:38:10 -0500
From:      Jon Loeliger <jdl@jdl.com>
To:        Kris Kennaway <kris@obsecurity.org>
Cc:        Peter Pentchev <roam@orbitel.bg>, security@freebsd.org
Subject:   Re: Security Check Diffs Question 
Message-ID:  <200107250038.TAA07176@chrome.jdl.com>
In-Reply-To: Your message of "Tue, 24 Jul 2001 15:47:11 PDT." <20010724154711.B36368@xor.obsecurity.org> 

next in thread | previous in thread | raw e-mail | index | archive | help
So, like Kris Kennaway was saying to me just the other day:
> 
> > ypchfn changed its inode number, and its link count.  This means that
> > somebody performed an unlink() (delete) on ypchfn, and then created
> > a new ypchfn with the same size, timestamp, permissions and stuff,
> > but still a new file - and that's where the hardlink count + inum
> > tracking of /etc/security kicked in and alerted you.
> 
> This is a signature I've seen before; chances are someone has gained
> root on your machine (probably through telnetd)

Excellent.  So given the grim situation, this is what I want to hear.
The system was compromised.  My suspicion is that telnetd was the
culprit, given it came on the heals of the telnet Security announcement.
No, I hadn't fixed it yet.  Man, there just isn't enough time in the
day to do your real job _and_ plug the security holes!  :-(

So the machine is currently off the air.  I'll rebuild it.
And would that be 4.4 or 4.3?  Rats.

I'm also going to set up a more serious DMZ firewall.  Can I ask
you guys questions and hold my hand through setting it all up?

I am not familiar with IPFW, but I know what it does, how it
works, networking and IP details.  So here's what I think I want
to set up now:

    - External ISP ISDN wire comes out of the wall,
    - Hits the Ascend Pipeline-50 and comes out ethernet,
    - Goes into a DMZ box on one ether card,
    - Same DMZ box has IPFW rules allowing traffic (or not)
      to be forwarded to the second ether card in that box,
    - The second ether card plugs into the 24-port switch,
    - Everything else on the "inside" plugs into that same switch.

For starters, do I have the basic scheme right?

( So I'm waiting on the high speed link to come up again,
  and eventually the Pipe-50 gets replaced with a T-1 LMC card.
  (Does FreeBSD have an LMC T-1 driver?  Or will I have to use
  this old POS Linux box for that?) )

You know, this is a pain!  But I appreciate your suggestions! :-)

jdl

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-security" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200107250038.TAA07176>