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Headphones can be hijacked to surreptitiously record audio

wired.com

71–80 of 158 posts

Re: Headphones can be hijacked to surreptitiously record audio

#71
post #67

One thing that's not clear from the article - are external headphones required for this to work? Can this not be done with the built-in speakers?

It seems like something that would work for built-in speakers too. They're driven by the same audio codec chips (eg realtek), but wired directly instead of through an external socket.

Re: Headphones can be hijacked to surreptitiously record audio

#72
post #56
post #54

Earlier quoted context omitted.

> Its not just recordings, but raw material to be edited and spliced together. "If one would give me six lines written by the hand of the most honest man, I would find something in them to have him hanged." ~ Cardinal Richelieu

Well, his thing was a culture where everyone was guilty of something and punishment was pretty harsh. To some extent like now. I'm sure I'm not recycling all my garbage precisely legally and that cap needs to be on (or off?) the creamer and I certainly was guilty of speeding this morning like everyone else on the road. I meant just outright fabrication. Record one conversation about my coworker being on vacation in n…

In the United States, at least, it's pretty likely that you're committing "crimes" unknowingly with some regularity. No fabrication is likely necessary if the authorities want to put you in a position of taking a plea bargain or gambling that you'll end up in prison. (See https://www.amazon.com/Three-Felonies-Day-Target-Innocent/dp... if this interests you.)

Re: Headphones can be hijacked to surreptitiously record audio

#73
post #59
post #51

Earlier quoted context omitted.

For starters, the fact that RealTek is so easily reprogrammable to turn audio output into input is very unlikely just a "bug". It's a feature left their on purpose.

It's a selling point. You plug anything at the back then change the jack's purpose in the control panel gui for the audio card.

Possibly, but why isn't the feature exposed to end users then?

Re: Headphones can be hijacked to surreptitiously record audio

#74
post #67

One thing that's not clear from the article - are external headphones required for this to work? Can this not be done with the built-in speakers?

Unlikely. There is going to be some sort of audio amplifier in the way that won't transfer signals very well in reverse. Even if it is built in to the audio chip there would be little point in allowing that output to be an input.

Re: Headphones can be hijacked to surreptitiously record audio

#75
post #73
post #59

Earlier quoted context omitted.

It's a selling point. You plug anything at the back then change the jack's purpose in the control panel gui for the audio card.

Possibly, but why isn't the feature exposed to end users then?

It is. I've seen it on multiple computers.

Re: Headphones can be hijacked to surreptitiously record audio

#76
post #67

One thing that's not clear from the article - are external headphones required for this to work? Can this not be done with the built-in speakers?

It seems like something that would work for built-in speakers too. They're driven by the same audio codec chips (eg realtek), but wired directly instead of through an external socket.

I think the opposite. Speakers are driven by an amplifier that will not let the audio in reverse, even if the soundcard output was switched to act as an input.

Re: Headphones can be hijacked to surreptitiously record audio

#78
post #55

Earlier quoted context omitted.

The error changes from not found to access denied.. Do you have a link to the paper?

Use f.e google cache to read it: cache: http://cyber.bgu.ac.il/advanced-cyber/system/files/SPEAKE%28...

HN missed the leading `cache:' and failed to make your link clickable. This ought to work:

http://webcache.googleusercontent.com/search?q=cache%3Ahttp%...

(I'm getting `access denied' on the original now too, but the Google cache link works.)

Re: Headphones can be hijacked to surreptitiously record audio

#79

makes me wonder if the same thing goes for screens, because the reverse photoelectric effect in LEDs can be reversed.

That reminded me of this Apple patent but it looks like this is done in a different method.

Apple files patent for camera hidden behind display http://appleinsider.com/articles/09/01/08/apple_files_patent...

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