Re: Tracking with ultrasound beacons. Web Audio API privacy considerations need updating?

That is a good idea.

But how do we separate out say, opting into a social network making noise
to tell me I have an instant message, from a social network making a noise
so they can engage in cross device tracking?

I can live without sound on say, Facebook, but it'll be harder on sites
like Youtube or Pandora.

-Greg

On Fri, Nov 13, 2015 at 6:12 PM, Alan deLespinasse <adelespinasse@gmail.com>
wrote:

> Personally, I think it would be great if browsers (by default) prevented
> pages from making sound without the user's explicit permission. Now that I
> think about it, I'm surprised I haven't seen this already. Is it an option
> that can be enabled in some browsers?
>
> Of course it should be possible to give permission to a given domain to
> make sound "from now on", so you don't have to give permission every time
> you go to Spotify or something. And there could be a global setting to
> allow sound for all sites, without asking. Pretty much like camera and
> microphone access is handled by most browsers.
>
> None of this sounds like an Audio API issue, though. More of a policy
> decision that could be left to browser developers and/or users.
>
> Also, note that the Web Audio API is not the only way to make sound in a
> web page.
>
> I really DON'T like the idea of "filtering out inaudible frequencies". One
> person's inaudible is another person's difference between high-quality and
> low-quality sound. (I'd be fine with banning all frequencies above ~20kHz,
> but (a) that would be fought by the "192kHz is better" placebo-hearers, and
> (b) anyone trying to do illicit tracking is more likely to use frequencies
> that most consumer hardware can handle.)
>
> I wonder if this kind of threat could be reduced by having some kind of
> cross-domain restrictions. I'm speculating recklessly and vaguely here. If
> the tracking-sound-emitter is likely to be part of an ad, which is likely
> to be loaded into an iframe, maybe it would help for iframes to have a
> separate sandbox permission for allowing audio. That way, at least, if I'm
> developing an ad-supported site, I don't have to worry about ad networks
> sneaking an ultrasonic tracker onto my site.
>
>
> On Fri, Nov 13, 2015 at 5:00 PM, Robert O'Callahan <robert@ocallahan.org>
> wrote:
>
>> On Fri, Nov 13, 2015 at 10:29 AM, Joseph Lorenzo Hall <joe@cdt.org>
>> wrote:
>>
>>> In some senses, platforms can help. E.g., just like there are small
>>> indicators present when an app is accessing location or the microphone to
>>> give users notice that something is using those resources, maybe a sound
>>> icon could be used? Chrome I think does this with tabs so that you can
>>> quickly identify which of dozens of tabs is the one playing annoying audio.
>>>
>>
>> Firefox does this too.
>>
>> Since this attack works for native apps as well, it's probably best
>> blocked by filtering out inaudible frequencies at the platform level.
>>
>> Also I imagine that if this gets used much in the wild, the scripts
>> involved will be added the blacklist used by Firefox's tracking protection.
>>
>> Rob
>> --
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>> uresyf toD
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>> rdsme,aoreseoouoto
>> o l euetiuruewFa  kbn e hnystoivateweh uresyf tulsa rehr  rdm  or rnea
>> lurpr
>> .a war hsrer holsa rodvted,t  nenh hneireseoouot.tniesiewaoeivatewt
>> sstvr  esn
>>
>
>


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