Thanks for all of the comments. I'm thinking about just suppressing those
alerts to the 169.254.0.0/16 range. The other strange thing about this that,
something I failed to mention in my original post, is the volume of these
alerts. It's not consistent across all of the machines. Usually, there will
be just one or two boxes out there that generate 300-400 of these types of
alerts over a 24-hour period. The next closest machine is usually generating
between 20 and 50 alerts. Then everything returns to normal.
For that reason, I think it might be something installed on those specific
computers that is generating all of that traffic. The traffic is probably
harmless, but now I'm curious. So I'm off to chase the wild goose!
:-)
AG
----- Original Message ----
From: Joel Esler <joel.esler@sourcefire.com>
To: dhottinger@harrisonburg.k12.va.us
Cc: snort-users@lists.sourceforge.net
Sent: Monday, February 25, 2008 5:02:04 PM
Subject: Re: [Snort-users] Strange portscan traffic with dest of 169.254.x.x
CunningPike had it right. When your machines can't find an IP (via
DHCP, or whatever), they default to the 169.254.x.x range.
Since your machines were contacting ports 139:445, I am willing to bet
that it's a Windows machine plugged into the network somewhere, (on
the same broadcast domain as your Snort sensor), and can't DHCP itself
for whatever reason.
My suggest is that you use Snort in sniffer mode like
#snort -vde 'net 169.254.x.x' look at the mac addresses. See if that
helps you out any.
Assigning these IPs should be the default behavior of both Windows and
OSX.
Joel
On Feb 25, 2008, at 5:47 PM, dhottinger@harrisonburg.k12.va.us wrote:
Quoting Aaron Giuoco <agiuoco@yahoo.com>:
True. But it is unusual to see so much traffic from 169.254 leaving
a computer that already has a network connection.
I haven't been able to confirm whether the packets are related to
ActiveSync like Paul mentioned. Thanks for the replies. I'll try
to confirm whether or not ActiveSync is being used on these PCs or
not and post back.
AG
I missed part of this post. However, I see lots of 169 traffic from
my apple 10.4, 10.5 computers. I think they use it for bonjour or
entourage, which is a way to find printers, and other network
resources.
--
Dwayne Hottinger
Network Administrator
Harrisonburg City Public Schools
"Everything should be made as simple as possible, but not simpler."
-- Albert Einstein
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Snort-users mailing list
Snort-users@lists.sourceforge.net
Go to this URL to change user options or unsubscribe:
https://lists.sourceforge.net/lists/listinfo/snort-users
Snort-users list archive:
http://www.geocrawler.com/redir-sf.php3?list=snort-users
--
Joel Esler ï joel.esler@sourcefire.com
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Snort-users mailing list
Snort-users@lists.sourceforge.net
Go to this URL to change user options or unsubscribe:
https://lists.sourceforge.net/lists/listinfo/snort-users
Snort-users list archive:
http://www.geocrawler.com/redir-sf.php3?list=snort-users
____________________________________________________________________________________
Looking for last minute shopping deals?
Find them fast with Yahoo! Search.
http://tools.search.yahoo.com/newsearch/category.php?category=shopping
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Snort-users mailing list
Snort-users@lists.sourceforge.net
Go to this URL to change user options or unsubscribe:
https://lists.sourceforge.net/lists/listinfo/snort-users
Snort-users list archive:
http://www.geocrawler.com/redir-sf.php3?list=snort-users
