This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
This will be fixed with a simple software update that ignores all sounds at inaudible frequencies.
Hackers send silent commands to speech recognition systems with ultrasound
11–20 of 88 posts
Re: Hackers send silent commands to speech recognition systems with ultrasound
#12This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
This will be fixed with a simple software update that ignores all sounds at inaudible frequencies.
The attack they are using is transmitting the audio at a high frequency, that when detected by the microphone generates harmonics that are within the normal range and can pass through the filter. By the time the audio signal gets to the processor, it is within audible range.
Re: Hackers send silent commands to speech recognition systems with ultrasound
#13This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
This will be fixed with a simple software update that ignores all sounds at inaudible frequencies.
>> This will be fixed with a simple software update that ignores all sounds at inaudible frequencies.
In the most helpful and constructive way I can possibly say this directly: the group of individuals not understanding may include you, rachitgupta.
According to my very limited understanding, the attack occurs in hardware prior to digitization. See yesterday's discussion for more details.
Re: Hackers send silent commands to speech recognition systems with ultrasound
#14This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
"hey siri" "show me pictures of CENSORED" "send the first picture to mom" "yes, send it"
:S
Re: Hackers send silent commands to speech recognition systems with ultrasound
#15This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
Yeah, those parts are easily available on Aliexpress in droves. Imagine this in the crowded subway. "hey siri" "show me pictures of CENSORED " "send the first picture to mom" "yes, send it" :S
Re: Hackers send silent commands to speech recognition systems with ultrasound
#16Earlier quoted context omitted.
Yeah, those parts are easily available on Aliexpress in droves. Imagine this in the crowded subway. "hey siri" "show me pictures of CENSORED " "send the first picture to mom" "yes, send it" :S
I’m pretty sure that Hey Siri is keyed to the users voice to some extent, so Siri should be safe. Not sure about Google, Cortana, Alexa etc.
Re: Hackers send silent commands to speech recognition systems with ultrasound
#17Earlier quoted context omitted.
Yeah, those parts are easily available on Aliexpress in droves. Imagine this in the crowded subway. "hey siri" "show me pictures of CENSORED " "send the first picture to mom" "yes, send it" :S
I’m pretty sure that Hey Siri is keyed to the users voice to some extent, so Siri should be safe. Not sure about Google, Cortana, Alexa etc.
Re: Hackers send silent commands to speech recognition systems with ultrasound
#18Re: Hackers send silent commands to speech recognition systems with ultrasound
#19Re: Hackers send silent commands to speech recognition systems with ultrasound
#20This is MUCH bigger deal than most understand. This will cost less than $10 to build and their is no hardware solution on phones or Alexia. Phreaking is back.
This will be fixed with a simple software update that ignores all sounds at inaudible frequencies.
The idea is that if you want to create a frequency of "A", you can emit two powerful tones at frequencies "B" and "B+A", where the frequency B is high enough to be out of hearing range. The non-linearity of the microphone means the two tones mix together to produce a number of other frequencies, including the frequency "B+A"-"B" = "A".
Thus the conversion from ultrasonics to audible is happening in the microphone itself, before the software has a chance to distinguish the difference. The mixing process typically produces other frequencies other than "A", so there might be hope of a countermeasure if the microphone is able to pick up these other frequencies and the software is smart enough to use them to figure out that an attack is in progress. It's not a simple case of just filtering out a particular frequency and an intelligent choice of ultrasonic frequencies may leave only a single frequency in the band of the microphone.
It's the same principle that is used in ultrasonic beamforming speakers. That adds another element of stealth to the attack, in that the high frequencies can allow the sound to be beamformed and illuminate the microphone and not much else.