[Cryptography] Useless side channels

[Alexander Klimov]

On Mon, 12 Feb 2018, Perry E. Metzger wrote:
> > A nitpick: Figure 9 (page 11) of <https://arxiv.org/pdf/1802.02317> 
> > shows a more realistic situation, where it is the smartphone that
> > is put inside a Faraday cage (bag) next to an air-gapped computer.
> 
> I don't consider that particularly realistic either I'm afraid.
> 
> If you can get software running on the target's phone, why are you
> bothering with this method of exfiltration when the thing has an LTE
> modem?

Once the data from an air-gapped computer is gathered by the phone, it 
will send it to attacker thru WiFi or modem.

> How often do people put their phones into Faraday cages while 
> they're still turned on (why not turn it off!?) as a method to 
> prevent data exfiltration?  If you're worried, why wouldn't you just 
> turn the phone off?

Many smartphones cannot be really turned off, that is you cannot 
disconnect the battery every time you report to work on an air-gapped 
computer, thus workers switch the phone off and put it into a Faraday 
bag for extra protection.

> lugging around a lot of test equipment

IIUC, there is no other "test equipment" except the compass in the 
phone.

-- 
Regards,
ASK