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Serious Hacks Possible Through Inaudible Ultrasound (newscientist.com)
An anonymous reader writes:
"High-frequency audio 'beacons' are embedded into TV commercials or browser ads," reports New Scientist. "These sounds, which are inaudible to the human ear, can be picked up by any nearby device that has a microphone and can then activate certain functions on that device...Some shopping reward apps, such as Shopkick, already use it to let retailers push department or aisle-specific ads and promotions to customers' phones as they shop."
But now Fortune reports that some apps "often actively listen for ultrasound signals, even when the app itself is closed, creating a new and relatively poorly-understood pathway for hacking." In addition, security researchers "have already found ways to mine cloaked IP addresses. Speaking to New Scientist, team member Vasilios Mavroudis suggests that an app's always-on microphone access could be leveraged to monitor conversations (and, if you're not paranoid already, to decipher what you're typing). The 'beacons' that transmit ultrasound data can also be spoofed to manipulate apps' user data."
But now Fortune reports that some apps "often actively listen for ultrasound signals, even when the app itself is closed, creating a new and relatively poorly-understood pathway for hacking." In addition, security researchers "have already found ways to mine cloaked IP addresses. Speaking to New Scientist, team member Vasilios Mavroudis suggests that an app's always-on microphone access could be leveraged to monitor conversations (and, if you're not paranoid already, to decipher what you're typing). The 'beacons' that transmit ultrasound data can also be spoofed to manipulate apps' user data."
Program LudditeApp wants access to the microphone?
Approve / Deny.
"High-frequency audio 'beacons' are embedded into TV commercials or browser ads," reports New Scientist. "These sounds, which are inaudible to the human ear, can be picked up by any nearby device that has a microphone and can then activate certain functions on that device..
Only in the dreams of the most tinfoil hatted idiots on the planet.
And slashdot editors, apparently.
No sig today...
This is assuming you even have a microphone that is ALWAYS listening. Which is not the case for the majority of devices as they at least require some some of use input.
If an app request microphone access for some reason even though the app itself has ZERO vocal interface, I just skip on the app. As should you.
And people wonder why I don't have a "smart"phone.
Anons need not reply. Questions end with a question mark.
Isn't ultrasound, by definition, inaudible to humans?
Simple, just put some tape over the mic!
Is it time to maybe - just as a precaution - have all the hardware manufuacturers of audio input & output chipsets filter out supersonic & subsonic frequencies before the rest of the machine even sees them?
Is there ever a case where someone would want inaudible frequencies to be processed by their device?
How difficult/expensive would it be to put such filters in place? The filters we put on our POTS devices to protect our xDSL seem to be pretty cheap..
"Inaudible Ultrasound"....as opposed to the other kind.
Just cruising through this digital world at 33 1/3 rpm...
Get a phone case that has RF blocking technology just like wallets are doing to prevent siphoning RFID chip data. Is this feasible for phones?
That's why we have anti-ultrasound-hacker dogs deployed.
First the radio, then the camera, then the microphone were configured as surveillance tools. Now the microphone also offers a backdoor into the operating system. What's this fascination with turning a phone (or more accurately, a portable computing device with telephony services) into the insecure IoT? Why can a macroscopic voice receiver detect ultrasonic audio? That's wasted performance when capturing the human voice.
It's time for cameras, microphones, and other sensors as well as the various radios to have hardware-on/off switches.
Yes, that would require you to turn the mic on by hand when you answer the phone, but the phone should be smart enough to know "if a call is coming in and the user turns the mic ON, answer the phone" (by default of course - this behavior should be user-controlled).
Heck, I'd even want one for my speaker and "flashlight/camera flash" to make it harder for a rogue app from using sound or light to exfiltrate data.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
and those in laptops, or headgear, about 8 kHz. TOPS! More scare shit to get attention.
If the NSA had wanted the citizenry to understand this pathway of hacking relatively well, they would have mentioned it a decade or two ago. My money is on the NSA's Kompromat psychographic dossier database.
Would any advertiser use an app that was biologically designed to repel young people in the prime shopping years?
As a musician (classical pianist) the mere idea that we can even get decent sound from a TV (or phone) is LOLable.
I recently did a search for near field monitors (flat response, for the studio only) and with a friend we put several high end speakers to the oscilloscope. Despite all of them claiming 20khz-20hz response, NONE of them achieved it. NONE. The ones I ended up buying (mackie) checked in ~16khz.
I think to really get 20khz that would have to be a 3-way speaker. Practically all TV speakers are full range one speaker rubbish that receive nearly universal derision from buyers who review them. And with good reason: you spend >$500 for a samsung TV and they literally probably spent ~$1 on the speakers. It's an insult.
The better soundbars are usually 2-way speaker systems and despite the $100-$200 cost the speakers are pure crap that maybe top out ~13khz (a range most people can hear).
TL;DR: shit speakers can't produce ultrasound frequencies.
2) The same goes for the mics. Total crap. And what idiot hasn't seen the mic block & camera block apps for the ADroid? Get with the fvcking program.
3) And I know most people are too lazy to do this, but when I install a phone app I do so using a permissions removing installer app. It's absolutely essential as damn near every app wants access to the net, billing & camera. NO CAN HAVE!!!
4) Where are these magical apps that aren't running but still processing data? That's an oxymoron, a paradox, aka a fvcking lie. And if they mean an app that is dormant, then I've got news for ya: that app is fvcking running. Just because it's not up front doesn't mean it's off.
5) "inaudible" sound manifests itself in speakers as distortion, fizzzz, or produces a tone on a resonant frequency... just like 20hz bass in a wav file makes your 100hz speakers resonate with that horrid vibration.
6) This entire article sounds like it was written by a fvcking idiot who doesn't know speaker from elbow... or ass.
For your phone:
1) Use an android phone. If you have an iPhone, forget it. There is no way to help you* on the iphone, except installing no apps at all.
2) Root your phone. I hope you thought about buying a rootable phone in step 1).
3) Install XPosed http://repo.xposed.info/
4) Install XPrivacy https://github.com/M66B/XPriva...
5) Consider donating for XPrivacy to get a Pro-Key and to help them develop this awesome project.
6) Think about installing AFWall+ as well, to cut internet access for some apps. XPrivacy can do this, but using AFWall is an easy way.
* Maybe with a jailbreak, i do not know the ecosystem of free apps for jailbroken iPhones. On the other hand, who wants to fight with apple all the time, who tries to lock you out again with each update? Just upgrade to an Android Phone. Nexus phones are a good choice.
Your incredulity is powered by arrogance.
I mean, to add a low-pass filter to the mic input.
One is your pocket acts as a low-pass filter. The higher frequency the sound, the smaller the wavelength, the smaller the wavelength, the less material you need to interfere with the sound wave. Try recording something with the phone sitting in your pocket sometime. Among other issues, you'll notice things are more "muffled" that the high frequency definition to them is not as good. That's because the high frequency sounds get messed with more than the low frequency ones by living in a pocket.
Also there's the issue of encoding. Never mind what the user's speakers are designed to do, the broadcast is not band unlimited. Like all digital broadcasts, it is band limited. Now it can be, and often is, band limited to 48kHz, which does allow for slightly ultrasonic frequencies (up to 24kHz) but we aren't done yet: It is compressed with lossy compression, specifically AC-3. This also implements a form of band limiting. Not only can it actually choose a frequency less than Nyquest to stop encoding at (which it does for lower bitrate streams) but in any case it doesn't spend nearly as much work on accurate encoding of high frequency information, since our ears are less sensitive to it. It spends bits getting the low and mid frequencies accurate first, not worrying so much about the ultra high ones.
There's an additional problem that AC-3 introduces, even for sounds in the audible range: It uses psycho-acoustic encoding. The idea is it throws away stuff that we can't hear, not just high frequency, but sounds that are masked by other sounds. The whole basis for it (and other lossy codecs) is "don't bother encoding it if humans won't notice it". So to make your encoded sound survive, it needs to be the kind of things that is likely to be audible to humans. If it is some very subtle, very high frequency modulation that is almost certainly the kind of thing a lossy codec would ignore.
While I certainly won't say this sort of thing is impossible, they really need to show some examples of it, before I'm willing to believe. It just relies on too many unlikely things to work.
This hack is only possible through Inaudible Ultrasound.
At least we're safe from audible Ultrasound.
Microphones with ultrasonic response are expensive. Nobody's putting them in mobile phones.
For the moments that your phone is on, YOU decide if your apps can use the microphone.
This should be standard in the Android OS. Tells you something about Google that it's not.