[gentoo-user] Heads up for those who use grub2

[gentoo-user] Heads up for those who use grub2

[Mick]

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http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

-- 
Regards,
Mick

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[gentoo-user] Re: Heads up for those who use grub2

[Grant Edwards]

On 2015-12-19, Mick <michaelkintzios@gmail.com> wrote:

> http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

If somebody can touch your computer while it's booting, the game's
over anyway...

-- 
Grant

Re: [gentoo-user] Re: Heads up for those who use grub2

[Rich Freeman]

On Sat, Dec 19, 2015 at 4:06 PM, Grant Edwards
<grant.b.edwards@gmail.com> wrote:
> On 2015-12-19, Mick <michaelkintzios@gmail.com> wrote:
>
>> http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html
>
> If somebody can touch your computer while it's booting, the game's
> over anyway...
>

Actually, not necessarily, though there is still room to go.

With a TPM-backed full disk encryption scheme you can basically
prevent most attacks based on physical control.  If you were to go a
step further and secure RAM and bus IO (we're not quite there yet) you
could probably make almost any hardware attack completely impractical.
If you have TPM-backed encryption and you assume the software itself
is secure then to attack it you're going to have to actually intercept
data off the bus, or from RAM.  You certainly can't just install some
rootkit by booting from alternate media, or remove the drives and
attack them from another device you control.  That is, unless you
defeat the TPM, which is certainly within the realm of the laws of
physics, but in practice everything about a TPM's design is intended
to prevent that attack.

-- 
Rich

Re: [gentoo-user] Heads up for those who use grub2

[Bertram Scharpf]

Hi,

On Saturday, 19. Dec 2015, 17:57:33 +0000, Mick wrote:
> 
> http://hmarco.org/bugs/CVE-2015-8370-Grub2-authentication-bypass.html

Decrementing an unsigned int without checking it for zero is
a real boner. Where things like that happen, you will find
more flaws.

Bertram

-- 
Bertram Scharpf
Stuttgart, Deutschland/Germany
http://www.bertram-scharpf.de