Snort mailing list archives

Re: Homenet Question


From: "Gibson, Samuel" <gibsons () my uwstout edu>
Date: Wed, 2 May 2012 21:40:40 +0000

Thanks guys.  I will try setting EXTERNAL_NET to !$HOME_NET.  


________________________________________
From: Ian Bowers [iggdawg () gmail com]
Sent: Wednesday, May 02, 2012 12:11 PM
To: Adam Gardner
Cc: Gibson, Samuel; snort-users () lists sourceforge net
Subject: Re: [Snort-users] Homenet Question

Alternately, if you have some reason for using "any" as EXTERNAL_NET, you can change the variable in the rule from 
EXTERNAL_NET to !$HOME_NET.  If you use PulledPork, place this in modifysid.conf :

2009702 "$EXTERNAL_NET" "!$HOME_NET"

However I imagine similar issue will come up in other rules.  Adam's solution is probably the best way to go.

-Ian

On Wed, May 2, 2012 at 10:13 AM, Adam Gardner <adamgardner502 () gmail com<mailto:adamgardner502 () gmail com>> wrote:
Since your $EXTERNAL_NET is set to "any" 10.0.0.0/8<http://10.0.0.0/8> is included in that.  You'll probably want to 
set $EXTERNAL_NET to !$HOME_NET.


On Wed, May 2, 2012 at 9:46 AM, Gibson, Samuel <gibsons () my uwstout edu<mailto:gibsons () my uwstout edu>> wrote:
Hello,

I am having an interesting issue with the homenet.  I have it setup in snort.conf as follows:

ipvar HOME_NET [10.0.0.0/8<http://10.0.0.0/8>]

ipvar EXTERNAL_NET any

ipvar DNS_Servers [10.1.2.3,10.1.2.4]

Which we have subnetted into internal networks similar to 10.1.2.x, 10.2.3.x and so on.  However our VPN clients use 
10.1.20.x/24.

Whenever a VPN Client registers itself in DNS after connecting, I get an ET POLICY DNS Update From External net  (Gen 1 
Sig 2009702)

The rule triggers, for example, with a source of 10.10.20.10 and a destination of 10.1.2.3

I can suppress this, but am mostly wondering if anyone has any insight into why the VPN is not being considered part of 
HOMENET.

Thanks,
Sam



------------------------------------------------------------------------------
Live Security Virtual Conference
Exclusive live event will cover all the ways today's security and
threat landscape has changed and how IT managers can respond. Discussions
will include endpoint security, mobile security and the latest in malware
threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
_______________________________________________
Snort-users mailing list
Snort-users () lists sourceforge net<mailto: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

Please visit http://blog.snort.org to stay current on all the latest Snort news!


------------------------------------------------------------------------------
Live Security Virtual Conference
Exclusive live event will cover all the ways today's security and
threat landscape has changed and how IT managers can respond. Discussions
will include endpoint security, mobile security and the latest in malware
threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
_______________________________________________
Snort-users mailing list
Snort-users () lists sourceforge net<mailto: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

Please visit http://blog.snort.org to stay current on all the latest Snort news!



------------------------------------------------------------------------------
Live Security Virtual Conference
Exclusive live event will cover all the ways today's security and 
threat landscape has changed and how IT managers can respond. Discussions 
will include endpoint security, mobile security and the latest in malware 
threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
_______________________________________________
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

Please visit http://blog.snort.org to stay current on all the latest Snort news!


Current thread: