RE: Snort false positive[Scanned]

["Omar A. Herrera" <omar.herrera () oissg org>]

Hi,

These false positives are common in internal networks if no tuning has been
done. 

The Readme.sfportscan file within the doc/ directory of the snort
distribution contains information on how to interpret these results and how
to fine tune this module.

Regards,

Omar Herrera

> -----Original Message-----
> From: Isidro Catalán Ramos 
>
> Hi list,
>
> We have Snort 2.4.4 and in the logs appear a lot of Port Scan traffic of
> this type:
>
> (portscan) TCP Portsweep
> (portscan) ICMP Sweep
> (portscan) UDP Portsweep
> (portscan) Open Port
>
> And the payload of this alerts is like the above:
>
> Payload (ASCII):
> Priority Count: 5.Co
> nnection Count: 4.IP
> Count: 14.Scanned I
> P Range: 192.168.1.9
> :65.54.171.28.Port/
> Proto Count: 8.Port/
> Proto Range: 80:3410
> .
>
> This alerts come from a lot of our network computers but they seems to
> be clean of spyware, worms, etc...
>
> We need to know if this is a false posivite or we have a problem in our
> LAN.
>
> Tanks!
> --


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