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Message-ID: <52D6BF9C.8070405@bluerosetech.com>
Date: Wed, 15 Jan 2014 09:04:28 -0800
From: Darren Pilgrim <list_freebsd@bluerosetech.com>
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Subject: Re: [FreeBSD-Announce] FreeBSD Errata Notice FreeBSD-EN-14:01.random
References: <201401142011.s0EKBoi7082738@freefall.freebsd.org>
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On 1/14/2014 12:11 PM, FreeBSD Errata Notices wrote:
> III. Impact
>
> Someone who has control over these hardware RNGs would be able to
> predicate the output from random(4) and urandom(4) devices and may be able
> to reveal unique keys that are used to encrypt data.

This is good to know, but I have to wonder:

If the attacker has that level of access to the hardware, I would expect 
one of two things is also true:

1. If you're on "bare metal", the attacker has firmware-level or 
physical access to the machine;
2. If you're on a hypervisor, you can't trust the hypervisor;

In both cases, I would think the attacker can use much simpler, more 
direct vectors and you have much worse things to worry about than the 
quality of /dev/random.  I'm not questioning the validity of the 
advisory, I'm genuinely curious about this.  I can't think of a scenario 
were someone could attack /dev/random using this vector without 1 or 2 
above also being true.