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Re: OpenSSH is a good choice?
From: Ron DuFresne <dufresne () winternet com>
Date: Thu, 23 Dec 2004 00:43:31 -0600 (CST)

On Wed, 22 Dec 2004, Willem Koenings wrote:

On Wed, 22 Dec 2004 02:40:25 -0600 (CST), Ron DuFresne
<dufresne () winternet com> wrote:

I'd disagree in that the tools are getting to be well enough defined that
we are all targets.  Best game is to restrict who has access to the ports
being served whenever possible, openssh has a history that makes this a
good service to limit this way.  Little need to hide what's not openly
allowed to all.

take a recent phpBB worm Santy for an example. worm seaches
automatically targets via google - it searches
viewtopic.php. if, for an example, you change that file name to
something else (and also all the referrings inside the phpBB so that
everything still works), then Santy does not find you phpBB as a
target. this is only an illustration to my point.

My thoughts on this have centered on the point that there are too many
decent scanning and banner grabbing tools out there to make botuse port
assingments off the default any much good at obscuring the service.

We are lucky in that most the coded sploits and POCs tend to be cheap in
that they tend to look for specifics in a very narrowly focused tunnel.
The potentials for something being crafted that is much more insidiously
inventive in determing attack vectors that might be non-norm are there.
And beaucse they remain at this time 'potential' should not be a reason or
rationale to try and place minimally effective or incomplete controls in
the security layers one uses.  The IT community has been repeatedly bitten
by doing less then they know better to do due to the potential of
something not yet unleashed, say 1988 for example.

i wrote my post because you say "the non std port advice is not worth
much". i have lot of cases, when non standard configuration reduces
first impact greatly. of course you shouldn't rely only to non
standard ports/configuration, but it is not totally worthless - it
often helps you a lot.

Perhaps I should have pre or post pended YMMV <grin!>.


Ron DuFresne
"Sometimes you get the blues because your baby leaves you. Sometimes you get'em
'cause she comes back." --B.B. King
        ***testing, only testing, and damn good at it too!***

OK, so you're a Ph.D.  Just don't touch anything.

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