Date: Mon, 8 Jul 2002 13:35:53 +0700 From: "Eko Suwarsono" <ekoz@melsa.net.id> To: <freebsd-questions@freebsd.org> Subject: Re: hiding OS name Message-ID: <002301c22649$b671bad0$d4e18aca@melsa.net.id> References: <006601c22627$a9199000$21020a0a@mti.itb.ac.id>
next in thread | previous in thread | raw e-mail | index | archive | help
There is several method to hiding your OS name/version or making a network
scanner like nmap will try harder to finished his job.
1. You can using "iplog" (using ports in /usr/ports/net/iplog), to fooling a
portscanner guess about OS specification.
2. Using ipfw with "Default To deny" policy, which closing all unusable
port.
3. Changing your sysctl "blackhole" parameter :
sysctl -w net.inet.tcp.blackhole=2
sysctl -w net.inet.udp.blackhole=1
4. Insert an option,
options TCP_DROP_SYNFIN # read in
/usr/src/sys/i386/conf/LINT
in your kernel configuration and recompile the kernel, but this method
not recommended if you are running webserver.
The first article/document you must read is freebsd's handbook, you can read
it at http://www.freebsd.org or go straight to
security chapter at
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/security.html, a
nice article about security you can found at :
http://www.defcon1.org/html/freebsd_security.html
http://www.onlamp.com/pub/a/bsd/2001/02/07/FreeBSD_Basics.html?page=1
or...http://www.google.com..:)
eko suwarsono
-----------------------------------------
use perl;
program fulfillment
----- Original Message -----
From: "Asep Ruspeni" <ruspeni@mti.itb.ac.id>
To: <freebsd-security@FreeBSD.ORG>
Sent: Monday, July 08, 2002 9:32 AM
Subject: hiding OS name
> I am newbie in FreeBSD OS, but i have lot of concerned in securing system.
>
> I have questions like this :
>
> - how can i set-up FreeBSD, so when it being scanned, it's show no
operating
> system name + version.
> - is there any articles i colud read about securing freeBSD such as the
> question i ask above.
>
> thank you in advance.
>
> -asep-
>
>
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-security" in the body of the message
>
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?002301c22649$b671bad0$d4e18aca>