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Date: Thu, 18 Oct 2012 15:26:54 +0200
From: Andre Oppermann <oppermann@networx.ch>
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To: h bagade <bagadeh@gmail.com>
Subject: Re: TCP_DROP_SYNFIN kernel option side effects?!
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On 16.10.2012 17:27, h bagade wrote:
> Hi all,
>
> I need to add this option to kernel in order to defeating Nmap
> OS-Fingerprinting. My system is running as Web Server and  also it is the
> gateway on the network.
> I want to know if setting this option has any side effects on other parts
> of the system? Is there any situation that SYN and FIN bits are set both in
> TCP packets? Is it a normal situation?

SYN and FIN is not normal. Doing TCP_DROP_SYNFIN is not RFC compliant
but doesn't cause any problems.

-- 
Andre