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Mailing List Logs for ShadowRN

Message no. 1
From: gurth@******.nl (Gurth)
Subject: [OT] MAC-addresses (was Re: Hacking a Smartlink in SR4)
Date: Wed, 05 Oct 2005 11:44:47 +0200
According to Derek Hyde, on 5-10-05 08:36 the word on the street was...

> It's what? Have you done much networking? MAC Filtering to only allow
> pre-programmed MAC addresses in the router, is one of the most difficult to
> get around methods of network security there is. It's far better than
> software firewalls or anything else of the sort, because if your MAC address
> doesn't match one in the list of acceptable MAC addresses, you simply don't
> have access to the network at all.

As a local ISP around here does: if their system detects you're using a
different MAC-address than the one you used before, it refuses you
access -- even if you go back to your old MAC. Unfortunately, they don't
inform you about the reason, so only if you phone them up they'll say
"Oh, you installed a new network card? I'll switch you back on."

Which, of course, I found out when helping a friend set up a new
computer with a new network card. It only took us about four hours
before we called it quits, and he phoned up the next morning...

> Yes, you can do that to make the router appear to be a specific PC, but only
> once you're ON the router and within it's network

True, to a degree. I'm not sure you can't access the router from
outside, though (I can't check this, obviously).

> (testing the theory in this manner
> isn't illegal, as, there's nothing illegal about trying to hack your own
> personal network).

Or my ISP's -- at least, for me, but not for you: "4.4 Without prejudice
to article 4.3, customers are permitted to hack the XS4ALL system."

> Routers are setup to be able to do that specifically
> because there are ISP's that work off of the PC's MAC address for
> authentication, and the router won't allow that MAC address to be seen as
> it's inside the network. It's the only way that you can use any form of
> network setup on such ISP's.

Unless you use the router from day 1, of course. But if you change it,
or add it later, then (as I illustrated above), it can become a problem.

Gurth@******.nl - Stone Age:
I'll let you be in my dream if I can be in yours
-> Possibly NAGEE Editor & ShadowRN GridSec * Triangle Virtuoso <-
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Further Reading

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