Re: Snort

[Martin Roesch <roesch () sourcefire com>]

Just one note from me.  If you're going to only pay attention to  
priority 1 events then you need to tune the priorities on your rules  
for your environment.  As Ron Gula pointed out in another message there  
are several products out there to correlate contextual information  
about your operational network environment with Snort's data  
<plug>Sourcefire's RNA</plug> to provide proper prioritization.  The  
problem with basic priority as it's generated by most IDSes is that the  
priorities are assigned to the *rules* instead of being based on the  
impact on your particular network ("contextualized").  The person who  
writes the rule/sig usually is the one that determines the priority  
which typically has little bearing on your network, so if you don't  
have some sort of automated correlation you need to go thru your tuned  
rule set and set the priorities manually to better match your network.

     -Marty

On Sep 29, 2004, at 5:52 AM, Alex Butcher, ISC/ISYS wrote:

> --On 27 September 2004 14:09 -0700 Jeremy Gonzales  
> <jerdgonzales () yahoo com> wrote:
>
> > Does anyone have experience with snort reports? How do
> > you deal with the loads of information? Is there a way
> > to  generate reports that eliminate the false
> > positives? Any help will be appreciated.
>
> 1) Tune your rules to eliminate false positives
> 2) Tune classification of rules (e.g. add new, more specific,  
> classifications and use them appropriately)
> 3) Tune priority of classifications
> 4) Only report on priority 1 events.
>
> Oinkmaster is useful for part 3, as you can use modifysid to change  
> the classtype based on part of the message (e.g. 'P2P' or 'CHAT').
>
> > Thanks,
> > Jeremy.
>
> Best Regards,
> Alex.
> --  
> Alex Butcher: Security & Integrity, Personal Computer Systems Group
> Information Systems and Computing             GPG Key ID: F9B27DC9
> GPG Fingerprint: D62A DD83 A0B8 D174 49C4 2849 832D 6C72 F9B2 7DC9
>
>
>
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--
Martin Roesch - Founder/CTO, Sourcefire Inc. - +1-410-290-1616
Sourcefire - Discover.  Determine.  Defend.
roesch () sourcefire com - http://www.sourcefire.com
Snort: Open Source Network IDS - http://www.snort.org


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