Re: port scan rule

[Jason <jason () brvenik com>]

You can't really block port scans, you can potentially block port scanners.

The problem is that a port scan can manifest in hundreds of ways, from
hundreds of sources, or be an errant typo from one person trying to connect
to a different system.

When you see an event for a port scan it means that the system identified
activity typical of a scan, you would then need to block the scanner
_entirely_ to prevent them from being able to continue the scan.

It is really a futile effort as it opens you up to trivial denial of
service.



On Thu, May 9, 2013 at 5:22 PM, Balla István <balla.bmf () gmail com> wrote:

> hey guys,
>
> could you tell me which rule should I set to drop if I wanna block all
> port scan?
>
> from my snort.conf:
>
> *preprocessor sfportscan: proto  { all } memcap { 10000000 } sense_level
> { medium } detect_ack_scan*s
>
> if i m right it only detects ack flags without 3w hs. my question is how
> to configure it to detect all port scans and which rules to set to drop?
>
>
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"Graph Databases" is the definitive new guide to graph databases and 
their applications. This 200-page book is written by three acclaimed 
leaders in the field. The early access version is available now. 
Download your free book today! http://p.sf.net/sfu/neotech_d2d_may

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