full-disclosure - Re: SYN ACK scans to random ports

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Date: Tue, 24 Sep 2013 16:34:15 +0200
From: Fabio <ctrlaltca@...il.com>
To: full-disclosure@...ts.grok.org.uk
Subject: Re: SYN ACK scans to random ports

Il 24/09/13 14:49, silence_is_best@...hmail.com ha scritto:
> Can someone explain the point of a SYN ACK scan to random high ports?  I
> usually see a fair amount of these...at first I thought it was maybe a
> block to an initiating SYN packet, but I don't see any evidence that the
> SYN ACK isn't the first packet seen.  Danke.

Typically an ACK or SYN ACK scan is used to map out firewall rulesets,
determining whether they are stateful or not and which ports are filtered.

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