Nice find Ali!

sorry this long, by I feel passionate about this...

Yet another disturbing insight into how exploitable
the modern PC is. To be 
fair, peaking into RAM of running systems has been
PoC'd more than a few times 
(as have a countermeasure or 2) all useless against a
fully unpowered system. 
Scary to have powered vs. not redefined though!

When I 1st started toying 10+ years ago with Norton
Your Eyes Only, E4M & later 
DriveCrypt it seemed the biggest issue after what
cipher, what app, was OS 
swapping RAM to disk either pagefile or for
hibernation. Yet for for years 
Crypto experts like Bruce Schneier and others have
been saying that no matter 
what, using general purpose computers to run
encryption software is flawed & 
exploitable.

It would seem that ultimately noting short of both
full RAM & storage encryption 
is going to prevent a running system from having it's
brains sucked out & 
scrutinized. We know of attempts with M$ XBOX, HDCP,
or HD-DVD/BluRay to secure 
against scrutiny. While they are seeing varying
degrees of success locking US 
out very little is coming in the form of letting us
lock THEM out. Obviously 
it's possible to build systems that once
set-in-motion, encrypt and continue to 
run leaving no "keys" in ram to sniff since only the
system knows what it's 
using to crypt/decrypt like Colossus & Guardian
talking to each other in a 
language only they knew!

Until then, on running systems, manual user
intervention is needed where 
auto-dismount is not practical. Passwords/phrases must
die, keys must be tied to 
a secure physical token so that removing it means
there are no keys. Removal of 
token should trigger memory wiping so keydata is not
cached. Some of this must 
already exist? I won't even go into EFS, it's default
lame option of obscuring 
the master keys in the registry, or the fact that mode
3 only works with floppies!

Now any system that can be suspended has got to be
easier to protect IMHO. If 
RAM sniffing an issue, then OTFE software needs to add
key flush on on suspend 
followed by re-authentication to retrieve keys from
external source (read not on 
the PC's RAM, HDD, SDD) on resume rather use RAM
cached copies. Don't know how 
easy that is to tie in, but I assume under the current
model apps have to wait 
for storage drivers to come back online after suspend
anyway so I imagine it how 
this hole gets closed. Personally I'd like to have a
encrypted hibernation file 
tied to a physical token for "plug & boot"
authentication.

Bottom line is time has come for *affordable*, faster,
dedicated hardware 
solutions to be made available. Either in the form of
TPM's in motherboards, 
storage devices, host controllers, or even inline
black boxes between device & 
host using a tamper-proof hardware solution. A
solution like the IronKey USB 
flash drive has between it's USB interface & flash
RAM. Give me a bunch of those 
modules in the form of SATA go-betweens & programmable
hardware security token 
I'd have all my SATA drives encrypted!


Mesdaq, Ali wrote:
> Interesting read for those into disk encryption
> 
> http://www.news.com/8301-13578_3-9876060-38.html
> 
> Thanks,
> ------------------------------------------
> Ali Mesdaq (CISSP, GIAC-GREM)
> Security Researcher II
> Websense Security Labs
> http://www.WebsenseSecurityLabs.com
> ------------------------------------------
> 
> 
>  Protected by Websense Messaging Security --
www.websense.com 
> 
> 


      
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