Re: Snort false positive

["Joel Esler" <eslerj () gmail com>]

Sounds like you need to tune your sfportscan preprocessor.

http://www.snort.org/docs/snort_htmanuals/htmanual_2.4/rc1/node11.html#SECTION00317000000000000000

Refer to above link for help.  Also be sure and subscribe to the
Snort-Users list at:
http://www.snort.org/community/lists.html

Joel

On 5/16/06, Isidro Catalán Ramos <icatalan () amigophone es> wrote:
> 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!
> --
>
>    Isidro Catalán Ramos
>    Administrador de sistemas
>   -----------------------
>       Amigophone S.L.
>    [ www.amigophone.es ]
>   -----------------------
>    Telf: +34 933 661 007
>    Fax:  +34 933 661 012
>    icatalan () amigophone es
>
>
>
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--
--Joel

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