[tor-relays] Exploiting firmware

[diffusae]

On 07.12.2016 23:50, Alex Haydock wrote:
> On 07/12/16 21:45, diffusae wrote:
>> Hmm, interesting subject ...
>>
>> On 07.12.2016 21:35, Gumby wrote:
>>>   Subject seems to have changed a bit, so not hijacking it.
>>> When thinking of any exploitation of firmware - should there be concerns
>>> of Intel's Management Engine in the CPU of any relays
>>>  running on "home hardware" in any common unused pc or laptop?
>>> Should that be a concern on ANY newer Intel hardware?
>>>
>>> Gumby
>> What do you think about Intel AMT, it's a part of the most modern PCs?
>>
> Intel ME/AMT concerns me too, especially how unavoidable it seems to be
> on modern CPUs (AMD is no escape, as they have an equivalent in the form
> of their "Platform Security Processor").
> 
> Though I this probably concerns me less than the fact that only the
> fastest relays are going to be deployed on colocated and fully
> owner-controlled hardware or under their own ASNs.
> 
> The rest are probably going to be VPS nodes or at least connected to
> some out-of-band network management interface for quick deployment and
> monitoring at the ISP-level. This can provide low-level access in a
> similar way to ME/AMT. I've seen many providers allowing access to
> management TTYs, or even raw disk management tools via HTTP web interfaces.
> 
> Abusing the ME/AMT would require some sort of co-operation on Intel's
> part, or stolen signing keys, but imagine if you could get access to
> some sort of administration panel for OVH/DigitalOcean etc. Co-opting a
> large number of relays/exits through that process might be a lot easier,
> so if I was going to worry about out-of-band management interfaces, I'd
> probably worry about those first.

I am totally agree with you.

One alternative would be to use coreboot on your machine. If you are
good, than you will put your kernel into the flash chip and make it
write protected.