PXE Booting

[o***@onetwo.com]

Hey pennies,

I performed an onsite pen test for a client who had network booting first in their BIOS boot order for their workstations. This was used to check for any updates that needed installing.

Therefore, as a demo, I setup a PXE server using CHAOS .. supercomputer for your wallet ;o) ... to force any system booting up to boot CHAOS and join my cluster - showing from there I theoretically had complete control of the underlying system.

My question is, what recommendations should I make to this client in relation to securing PXE booting? ... or any other useful suggestions that people feel like they have to make, like "Dont use PXE booting"! ;o)

Thanks,
One2

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[Andy Meyers]

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How bout boot directly to the hard drive unless otherwise needed and
password protecting the BIOS? And if possible password protect the boot
device selection.


- -----------
Ashes
PGP: http://ashesbelow.ath.cx/public.txt

- -----Original Message-----
From: ***@onetwo.com [mailto:***@onetwo.com]
Sent: Monday, June 26, 2006 9:21 PM
To: pen-***@securityfocus.com
Subject: PXE Booting

Hey pennies,

I performed an onsite pen test for a client who had network booting first
in their BIOS boot order for their workstations. This was used to check for
any updates that needed installing.

Therefore, as a demo, I setup a PXE server using CHAOS .. supercomputer for
your wallet ;o) ... to force any system booting up to boot CHAOS and join
my cluster - showing from there I theoretically had complete control of the
underlying system.

My question is, what recommendations should I make to this client in
relation to securing PXE booting? ... or any other useful suggestions that
people feel like they have to make, like "Dont use PXE booting"! ;o)

Thanks,
One2

-
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Concerned about Web Application Security?
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Choice Award from eWeek. As attacks through web applications continue to
rise, you need to proactively protect your applications from hackers.
Cenzic has the most comprehensive solutions to meet your application
security penetration testing and vulnerability management needs. You have
an option to go with a managed service (Cenzic ClickToSecure) or an
enterprise software (Cenzic Hailstorm). Download FREE whitepaper on how a
managed service can help you: http://www.cenzic.com/news_events/wpappsec.php
And, now for a limited time we can do a FREE audit for you to confirm your
results from other product. Contact us at ***@cenzic.com for details.
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you need to proactively protect your applications from hackers. Cenzic has the
most comprehensive solutions to meet your application security penetration
testing and vulnerability management needs. You have an option to go with a
managed service (Cenzic ClickToSecure) or an enterprise software
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[Tonnerre Lombard]

Salut,

Post by o***@onetwo.com
My question is, what recommendations should I make to this client in relation to securing PXE booting? ... or any other useful suggestions that people feel like they have to make, like "Dont use PXE booting"! ;o)

And old-fashioned solution would be to burn the image onto a boot ROM
and stuff that one onto the NIC. It's a bit harder to change from
software.

Tonnerre

[Akeru Ikena]

Post by o***@onetwo.com
My question is, what recommendations should I make to this client in relation to securing
PXE booting? ... or any other useful suggestions that people feel like they have to make,
like "Dont use PXE booting"! ;o)

There are some cases where PXE booting is really useful (quick
replications of clustered machines comes to mind). What I would look
into for this issue is DHCP Snooping, this is a common solution and a
rather simple one to ensure the security of the PXE Booting process.

Cheers,
A.

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you need to proactively protect your applications from hackers. Cenzic has the
most comprehensive solutions to meet your application security penetration
testing and vulnerability management needs. You have an option to go with a
managed service (Cenzic ClickToSecure) or an enterprise software
(Cenzic Hailstorm). Download FREE whitepaper on how a managed service can
help you: http://www.cenzic.com/news_events/wpappsec.php
And, now for a limited time we can do a FREE audit for you to confirm your
results from other product. Contact us at ***@cenzic.com for details.
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[AdamT]

Post by o***@onetwo.com
Hey pennies,
My question is, what recommendations should I make to this client in relation to securing PXE booting? ... or any other useful suggestions that people feel like they have to make, like "Dont use PXE booting"! ;o)

I'll second the recommendations to lock down BIOS configurations with
a password, and place HDD at the top of the boot order. Some BIOS
chips allow you to have a separate password that allows somebody to
select a boot device, without allowing them to make any permanent
changes. That could be useful for 2nd line support staff, who will
need to initiate a network or CD-ROM boot.

If you're worried about rogue PXE boot servers - don't they need to
assign an IP address first, and could that not be filtered out by a
layer 2 switch?
--
AdamT
"A casual stroll through the lunatic asylum shows that faith does not
prove anything." - Nietzsche

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Why not go with the #1 solution - Cenzic, the only one to win the Analyst's
Choice Award from eWeek. As attacks through web applications continue to rise,
you need to proactively protect your applications from hackers. Cenzic has the
most comprehensive solutions to meet your application security penetration
testing and vulnerability management needs. You have an option to go with a
managed service (Cenzic ClickToSecure) or an enterprise software
(Cenzic Hailstorm). Download FREE whitepaper on how a managed service can
help you: http://www.cenzic.com/news_events/wpappsec.php
And, now for a limited time we can do a FREE audit for you to confirm your
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