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Security Researchers Can Turn Headphones Into Microphones (techcrunch.com)
As if we don't already have enough devices that can listen in on our conversations, security researchers at Israel's Ben Gurion University have created malware that will turn your headphones into microphones that can slyly record your conversations. TechCrunch reports: The proof-of-concept, called "Speake(a)r," first turned headphones connected to a PC into microphones and then tested the quality of sound recorded by a microphone vs. headphones on a target PC. In short, the headphones were nearly as good as an unpowered microphone at picking up audio in a room. It essentially "retasks" the RealTek audio codec chip output found in many desktop computers into an input channel. This means you can plug your headphones into a seemingly output-only jack and hackers can still listen in. This isn't a driver fix, either. The embedded chip does not allow users to properly prevent this hack which means your earbuds or nice cans could start picking up conversations instantly. In fact, even if you disable your microphone, a computer with a RealTek chip could still be hacked and exploited without your knowledge. The sound quality, as shown by this chart, is pretty much the same for a dedicated microphone and headphones. The researchers have published a video on YouTube demonstrating how this malware works.
You don't have to be a security researcher to do that. Electrical engineers can do it as well. The point of the article is the privacy and security implications that come from malware that can switch I/O audio jacks using software toggles found in audio drivers and secretly record you while you have your headphones or simple speakers plugged in.
Use a headphone preamp or even cheap active speakers.
Would it work with amplifier+speakers ?
Real hackers pull this stunt through wireless headphones.
is a microphone. Both headphones and microphone share the same mechanism (using a voice coil). The microphone is more sensitive (as it generates small alternative current when the sound makes the diaphragm vibrate) ; and headphones do the opposite, its diaphragm vibrates when the device injects positive or negative current. Even a bigger speaker is sensitive enough to act as a microphone.
Slashdot, fix the reply notifications... You won't get away with it...
Apple apparently saw this one coming :)
unpowered analog speakers and microphones are basically the same parts. Guess people aren't aware a headphone works as a mic. The only trick here is they could get the audio output chip to report back the electrical level to the computer.
Take any headphones plug them into the mic jack and speak at will.. This is NOT rocket science, and if it is I was a rocket scientist at the early age of 11. this is just forcing a mic driver to install on the headphone jack. I could script this in less then 2 mins and I have no degree.
Why not just use the microphone? There's one on most headphones these days.
I've noticed it's been possible to retask ports for input output on most sound cards or both for a long time... The smaller the headphone the better it would work as a passive microphone, I thought this was always obvious. This is hardly something that no one ever though of before like air gap hacks.
I figured that out when I was 8!
Slow researchers!
(In seriousness, its a nice hack. Now excuse me while I put black electrical tape over all my microphones... oh wait...)
On the whole, I find that I prefer Slashdot posts to twitter ones because I don't get limited to 140 chars before
Does it work on that too if you dont have any other audio?
...I plugged a cheap microphone into a headphone jack and heard sound. Like you said, old news.
Not only do they make bad networking chipsets, their audio chipsets are even worse.
Twitter supports and protects racists - by smearing their critics with the "Hate Speech" label.
I have been using my headphones as a microphone because i didn't have a microphone when i was a kid ~20 years ago. Almost all audio cards can be programmed to use each connector either as "speaker" or as "mircrophone". So i am wondering how this is news?
Go to hell, Nazi. Every developed country has security researchers in its universities.
This hack won't work on your iPhone 7. Now they can never turn it into a device that can pick up sounds at any time... Oh...
Who would have thought that all of that Big Brother monitoring equipment was really just the various entertainment devices Winston had saved for over many months.
This could be quite useful
Not only do they make bad networking chipsets, their audio chipsets are even worse.
I'm with you on the rtl eth, but being able to switch inputs in the codec is a feature, not a bug. It enables you to do stuff like plug in a device, answer a question about what it is, and not have to worry about which port is which. It also lets you have multiple inputs or multiple outputs with just two jacks, which would often be useful on a laptop.
The problem isn't in the hardware, it's in the software.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
At least for the cards I have had for the last 10 years you have a color for the plug and you can choose *at the moment* you plug in if it should act as headphone, as microphone, it is not set as "in" or "out" you can even switch them around and it sitll work properly. If the driver can chose, then the driver can be misused to switch around and amde believe headphone/loudpseaker are (poor) microphone
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Good grief! We were doing this in the early 60s when the carbon microphones in our headsets crapped out. Switching earpeice between ear & mouth gave us half vs full duplex comms too... :)
This is what happens when you have software switches and single ports capable of working as mic and headsets.
Even TVs in the 80s had distinct IO.
Hell, there were even adaptors for two-way ports to allow one-way communication only.
This could be used to choose specifically what device you want to be a master and which the slave, useful for doing special effects in hardware only. (which I found out accidentally as a KID of 13)
Of course, these days many more crappy headphones are going through USB, which is even worse.
Or infinitely worse, BLUETOOTH.
The new iPhone 7 - even more courageous and secure.....
So what's new? Everyone who's a bit a home in such things knows that a classic speaker (magnet and membrane, not piezo ones) and a classic microphone (magnet and membrane, not capacitive types) are exactly the same thing, save mechanical differences aimed at making them somewhat better at what they're being designed for than at working the other way around.
And everyone who has looked closely at the settings of the most common audio chips in their PCs knows that input and output are somewhat relative, because each jack can be reprogrammed to be any of a few different functions.
It's not like nobody came up with this idea before. I know *I* did, I just didn't believe it merited calling myself a security researcher because of it.
This even reminds me of the 1970's, when I did silly things like plug a microphone into a cassette recorder headphone jack and listen to sound coming (faintly, I admit) out of the mike. And I'll even admit that the first time I did it was by accident, and made me fear I had ruined the mike. Which would be something "not good" for a teenager.
And BTW, Realtek did good. Making jacks configurable is not bad design. Calling that a bug *is* negative thinking.
i dont know how this is even news, ive been able to plug headphones into the mic port and collect sound since windows 95. the physics behind microphones and speakers are the exact same thing with the only difference being in the direction of application.
Then in windows 98 you were able to start retasking ports for different things. this is not a hack, this is a feature that has been implemented into audio drivers for years to allow people to use 5.1 and more speakers for their setups. computers with built in speakers like most laptops can do this as well.
I've noticed it's been possible to retask ports for input output on most sound cards or both for a long time... The smaller the headphone the better it would work as a passive microphone, I thought this was always obvious. This is hardly something that no one ever though of before like air gap hacks.
Every speaker can be turned into a microphone. duh.
Who needs to hack into anything when we are installing home automation devices like Amazon Alexa Echo and Google Home that stream audio to the cloud. In the case of the Echo its 16bit, 16KHz audio with a sophisticated microphone array that can determine the direction of the conversation. Both Google and Amazon are proud of their voice recognition capabilities.
How do you know it is only sending audio when you talk to it? Blinking LEDs? See discussion about software control of indicator LEDs.
In Soviet Russia, microphones are speakers.
Your smartphone has a microphone (or three) you can't easily disconect and the radios part runs closed and obscured software that probabbly accepts remote commands.
Your laptop has a built in microphone and laptop jacks have been for a while compatible with 4 rings jacks so if you use your phone's headphones you have another microphone connected.
Many smart tv's have mics as well.
Most of the above have webcams but at least you can cover those. You can't cover a mic with the gain cranked up to 11.
I used to work as a sound engineer for conferences some 10 years ago and for giggles I would route one of the backup mic's to my headphones and crank the gain really high. I could hear what panel members whispered 10 seats away.
I wonder how soon until they can subvert tin foil hats?
put an amplifier or isolator between the jack and the speaker. Security problem gone.
I knew about this since I plugged in my headphones backwards on pc sound card 10 years ago.
The first time I plugged into the headphone jack and Windows popped up a notification that it knew about it.
Would a diode put a stop to this?
So... how can I invoke this deliberately? I would *love* to swap my laptop's line-in/out in software, because one port's never been used and the other is damaged beyond repair.