Re: Unexpected results with reputation preprocessor

[Dave Corsello <snort-users () wintertreemedia com>]

My last sentence was unclear.  I should have said that the preprocessor
seems to be reporting a non-existent outbound HTTP packet for each
blocked inbound _HTTP_ packet.

On 3/19/2014 3:22 PM, Dave Corsello wrote:
> Thanks Joel and James.  The problem is that according to my maillog the
> preprocessor did its job--the inbound traffic never made it to my
> server, so there was no outbound response traffic.  It looks to me like
> for each inbound packet that the preprocessor reports, it's also
> reporting a second, non-existent packet with all of the same
> information, including timestamp, except that the source and destination
> addresses are reversed.  I also see this at a client location where I
> recently upgraded to 2.9.6.0 and turned on the reputation preprocessor. 
> In that case, assuming that the inbound traffic was successfully
> blocked, the preprocessor seems to be reporting a non-existent outbound
> HTTP packet for each blocked inbound packet.
>
> On 3/19/2014 1:42 PM, James Lay wrote:
> > On 2014-03-19 10:34, Joel Esler (jesler) wrote:
> > > You could suppress by destination IP.
> > >
> > > But I’d warrant that if you have an internal host going outbound to
> > > an externally reputation blocked IP, then that’s a problem too!
> > >
> > > --
> > > Joel Esler
> > > Open Source Manager
> > > Threat Intelligence Team Lead
> > > Vulnerability Research Team
> > >
> > > On Mar 19, 2014, at 10:13 AM, Dave Corsello
> > > <snort-users () wintertreemedia com> wrote:
> > >
> > > > Folks,
> > > >
> > > > Any ideas on how to prevent the reputation preprocessor from 
> > > > producing
> > > > alerts on both inbound and outbound traffic in cases where there is 
> > > > only
> > > > inbound traffic?  Trying to determine whether the traffic was 
> > > > inbound or
> > > > outbound can be time consuming.  Apologies for assuming that Snort 
> > > > is in
> > > > error in my last message.  I certainly could be doing something 
> > > > wrong.
> > > >
> > > > Thanks,
> > > > Dave
> > People that run mail servers with realtime blocklists will most likely 
> > see a fair amount of these.
> >
> > James
> >
> > ------------------------------------------------------------------------------
> > Learn Graph Databases - Download FREE O'Reilly Book
> > "Graph Databases" is the definitive new guide to graph databases and their
> > applications. Written by three acclaimed leaders in the field,
> > this first edition is now available. Download your free book today!
> > http://p.sf.net/sfu/13534_NeoTech
> > _______________________________________________
> > 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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users
> >
> > Please visit http://blog.snort.org to stay current on all the latest Snort news!
>
> ------------------------------------------------------------------------------
> Learn Graph Databases - Download FREE O'Reilly Book
> "Graph Databases" is the definitive new guide to graph databases and their
> applications. Written by three acclaimed leaders in the field,
> this first edition is now available. Download your free book today!
> http://p.sf.net/sfu/13534_NeoTech
> _______________________________________________
> 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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users
>
> Please visit http://blog.snort.org to stay current on all the latest Snort news!


------------------------------------------------------------------------------
Learn Graph Databases - Download FREE O'Reilly Book
"Graph Databases" is the definitive new guide to graph databases and their
applications. Written by three acclaimed leaders in the field,
this first edition is now available. Download your free book today!
http://p.sf.net/sfu/13534_NeoTech
_______________________________________________
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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users

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