Snooping TV.

Mar 10, 2017 282 Replies

Maybe not simple, but there are some advantages in putting the mic in (almost) the same place as the sound source. This is fundamentally no different from what the echo canceller in a hands-free speakerphone does. They can work very well in full duplex so long as the speaker and mic are reasonably linear. The echo canceller knows what the drive to the speakers is and can deal with frequency response variations.

Cheap electret mics are very linear over a reasonable range of sound pressures. Their noise floor is not anywhere near as good as studio mics, but is probably good enough for use in a normal room. They don't usually cope very well with high sound pressure levels, but again this is unlikely to be a problem in this situation.

John

Its important to realise that when talking about nation state security services, to all intents and purposes they do have unlimited resources.

It would require a patch certainly - but hardly a rewrite.

Many internet routers are insecure anyway. Snowden et al made it clear that they the NSA have back doors into many popular bits of networking infrastructure.

One would hope it would be targeted to individuals or organisations of interest. However if they can get away with it as a blanket measure, I am sure they would not object!

Why risk sending in an operative when they can do it from their office? Also unlike a federal wiretap, they don't (as yet) require judicial oversight for internet "taps" IIUC.

Yours in particular? Don't know.

However others expect things like voice control and the ability to Skype from the TV.

ISTR there was one box that actually increased its power consumption in standby - since the only difference was standby had an addition LED lit to indicate it was in standby - everything else was still running the same.

Of course. That's all the proof dennis needs. ;-)

Depends on what you mean by powered. Modern CPUs have very low quiescent power draw when in a halt state. So its quite common to simply halt in the scheduler and then wait for a interrupt to wake it. That could be a periodic clock tick or some other event of interest.

Indeed. That's an average of 1W though. The likely power vs time graph may well show milli or micro watts for extended periods of time, with periodic bursts of higher consumption.

(one of the reasons its impossible to measure the current draw on low power electronics with a ammeter. You have to use a digital storage scope to capture the current drawer over an extended block of time, and then integrate the area under the curve)

Very true. Now try your hands free speaker phone from the other side of the room. More akin to a TV set picking up dialogue in a room. And see how well it works with say a radio on in the room.

Even when the manufacturer is not complicit, they have other solutions, as they demonstrated when cisco refused to allow them to embed code in routers destined for certain customers. So instead they just intercepted the devices after they were shipped, but before reaching the end user, and modded them then.

Ignoring the link to the product they won't sell you then?

if it's encrypted you need to know the secret (aka private) key

performing the certification is easy for you to do yourself if you know that

impossible for anyone if you don't

tim

not on my router

almost as soon as I turn my TV devices off they are removed from the list

no, the protocol standards are irrelevant

What you need to know is the precise operation of your own devices

and I do

tim

I can see their Mac addresses, which I can match up with what the device claims is their Mac address

I have a desktop connected via Ethernet

It shows this connection separately to the wireless connected devices

(and that's such a common situation, I'm surprised you even needed to ask)

tim

The last West End production I went to had no intelligible sound whatsoever.

Would an expensive microphone work significantly better if it were located in the same place as the cheap one?

John

But not, apparently, when it came to accessing the data on a locked phone?

Seems pretty major to me.

1) Alter the power LED software so it shows off when actually on. 2) Totally blank the screen (and audio) so there is no indication it is on. 3) Arrange for the software to allow it to be powered up via a network command (or simply have it powered up at all times) 4) Make sure it isn't visible to other devices on the LAN in this stealth mode.

Seems to me relying on a spy etc to not have any decent security is not the best plan.

If they already know who to target, things do become easier. But we constantly get told on here etc about the big brother syndrome where *everything* *anyone* says is logged and acted on.

Then easy to disable?

When we get some true evidence that some dastardly plot has been avoided by such a method, I'll be more inclined to believe it. But they are commonly found by the more usual way of intercepting mobile phones and computer data.

Until them I'll take it as just another heavily hyped big brother scare.

But you can't deny you heard every word :)

Thank you for the lesson in public key cryptography. Not sure it helps in this particular case.

I would expect that if you are a government sponsored spook, you will have access to a tame legit certification authority that is established in the root certificate hierarchy of trust. Hence you can sign anything you like as genuine. In addition to that there are a number of certification authorities that are none to fussy about what they sign.

For example:

formatting link

A fair point ... even if the router is nobbled, so as to show no activity from the compromised TV, it's possible the dirty tricks could show up in the billing of an ISP charging by the byte - as most mobile networks tend to.

I am reminded of an episode of Rumpole where TPTB were forced to keep his phone line working despite his letting it run into severe arrears.

Which leads us back to the key weakness of conspiracy theories - the scope creep of adding in more players and tweaks, as the underlying premise is questioned.

So have GCHQ/NSA/whoever *also* done backroom deals with Vodafone, EE, Three, etc to be able to remove "spy data" from a subscribers regular data ? If not, then for all their gee-whizzery, they run the risk of a victim wondering why they have no data allowance left, despite never using a single device ....

unless - as I suggested upthread - your router is nobbled.

Not impossible, just time consuming. Encryption is always a compromise between how long it takes to code/decode and how long it takes to crack. For things with a limited time where a crack maybe useful you don't need strong encryption and it may only take hours to crack. For others it may take weeks, months/years to crack but don't expect it to be uncrackable if someone can throw enough resources at it.

For example a home PC can crack a wifi password in a few hours, a home computer with a couple of nvidia cards can do it in tens of minutes, GCHQ can probably crack it in seconds (all after collecting enough data to start the processing). What this means is that you are probably safe from the average hacker as modern wifi changes the encryption frequently so the hacker is always going to be in the past as far as accessing the network is concerned, however that doesn't mean they can't access the past data at some time.

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