Traditional keyboard sounds can be decoded, compromising privacy

October 19, 2016
"People who talk on Skype are not always friends and do not always have mutual trust," says study co-author Gene Tsudik, Chancellor's Professor of computer science at UCI. "Imagine a call between lawyers on opposite sides of a legal case – or business competitors or diplomats representing different countries." Credit: Steve Zylius / UCI

If you type on your desktop or laptop computer's keyboard while participating in a Skype call, you could be vulnerable to electronic eavesdropping, according to researchers at the University of California, Irvine and in Italy.

In a new study published online at arXiv, they describe a whereby keystroke sounds, or acoustic emanations, can be recorded during a Skype voice or video call and later reassembled as text.

"Skype is used by a huge number of people worldwide," said co-author Gene Tsudik, Chancellor's Professor of computer science at UCI. "We have shown that during a Skype video or audio conference, your keystrokes are subject to recording and analysis by your call partners. They can learn exactly what you type, including confidential information such as passwords and other very personal stuff."

He specified that such an attack is not possible with touch-screen or holographic keyboards and keypads. And since data transfer over Skype is encrypted, it's extremely difficult for someone who's not part of a call to pilfer keystrokes. However, he outlined scenarios in which this cybersecurity threat could be all too real.

"The interesting thing is that people who talk on Skype are not always friends and do not always have mutual trust," Tsudik said. "Imagine a call between lawyers on opposite sides of a legal case – or business competitors or diplomats representing different countries."

Security experts have long known of attackers' ability to capture acoustic signals from typewriters and computer keyboards for nefarious purposes. Various brands of keyboards, from Apple to HP to Logitech, emit distinct sounds. That information combined with some knowledge of a user's typing style could be enough to allow a spy to re-create whole texts.

"It's possible to build a profile of the acoustic emanation generated by each key on a given keyboard," Tsudik said. "For example, the T on a MacBook Pro 'sounds' different from the same letter on another manufacturer's product. It also sounds different from the R on the same keyboard, which is right next to T."

He said that if the sound of someone typing is recorded, each keystroke can be analyzed and matched to a key using machine learning techniques.

The challenge in such attacks has been finding a way to place a recording device near a victim's computer keyboard. Now the recording can be done remotely if a person is typing while utilizing a voice-over-internet-protocol application, such as Skype, Google Hangouts or Vonage.

The study found that if attackers have some knowledge of the typist's style and information about the keyboard, they have a 91.7 percent rate of accuracy in guessing a key pressed by the victim. If snoops are oblivious to both the typing style and keyboard, they still have a 41.89 percent chance of identifying which keys are being struck, since the English language has a well-known frequency distribution of letters.

"Our work is yet another nail in the coffin of traditional physical keyboards that are common in modern laptop and desktop computers," Tsudik said. "It clearly shows previously unnoticed privacy dangers of using popular VoIP technologies in conjunction with such keyboards."

The touch-screen keyboards on many smaller devices, such as smartphones and tablets, are not susceptible to these attacks. Laser projection, or holographic, keyboards are also immune.

Explore further: Research proposes background noise to prevent side channel attacks on computer keyboards

More information: Don't Skype & Type! Acoustic Eavesdropping in Voice-Over-IP. arxiv.org/pdf/1609.09359.pdf

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42 comments

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gkam
1 / 5 (5) Oct 27, 2016
This was a concern decades ago for the government. While giving a technical course in powerline harmonics for Sandia Labs in Livermore, we found they were concerned tapping the powerlines could let others trace the keystrokes of those on computers. We taught security techniques.

At the Blue Cube near Moffitt Field, outdoor isolation transformers provided power to motors which drove generators inside the building with snubbing connectors to provide power to the facility for downloading signals from satellites.
Uncle Ira
4.2 / 5 (5) Oct 27, 2016
This was a concern decades ago for the government.
Are you claiming the peoples who did do this study plagiarized the concept from "decades ago"?

While giving a technical course in powerline harmonics for Sandia Labs in Livermore,
That is a bit over the top even for you Cher. Sandia Labs and Livermore have hundreds of PhD's on staff and thousands of real engineers, but they are going to go hire a guy wearing a silly looking pointy cap with stars and moons on him to give a course on harmonics?

We taught security techniques.
Sure, Sandia Labs and Livermore doing all their DoD and DoE and NASA classified work would seek out the glam-Skippy to teach them security. You been smoking pot early today, eh?

Cher, this article is not about keylogging. It's about the sounds and rhythms of key clacking.
gkam
1 / 5 (5) Oct 27, 2016
Poor Ira, apparently does not know I sold about seven or eight copies of my Power Quality Manual to the Librarian at Sandia National Labs after the course.

Two of us presented that three-day course, and found some wiring problems in the building we used, right outside the door of the room we were in. A lighting circuit had a few Amps through the steeltube, indicating a probable Neutral-to-Ground connection in a fixture.

But all the electrical panels had the covers welded to the panels, and we had to get folk with grinders to remove them for measurements. The problem seems to be that everything gets so many inspections, everybody expects them to be perfect, and they are not rigorously checked.

There may be another copy of that Sandia manual here, and if Ira has fifty bucks, he can have it.
Uncle Ira
5 / 5 (4) Oct 27, 2016
Poor Ira, apparently does not know I sold about seven or eight copies of my Power Quality manual to the Librarian at Sandia National Labs after the course.
Non Cher, not poor Ira-Skippy. I bet nobody else knows either including the Librarian at Sandia National Labs.

Two of us presented that three-day course,
Now Cher, put down the pot for just a second and think. Do you really think that makes sense? That Sandia National Labs with all their hundreds of PhD's and thousands of professional engineers are going to go outside, to an non-degreed, non-licensed non-electrical engineer (wearing a silly looking pointy cap with stars and moons on him) to come in and teach them a course on power and harmonics? And advise them on security?

If you think that makes a good war story Cher, your mental conditions and pot smoking is doing worse to your brain than we suspected.
Captain Stumpy
4.2 / 5 (5) Oct 27, 2016
@STOLEN VALOR LIAR-kam superNSAspy
I sold about seven or eight copies of my Power Quality Manual
ISBN
or STFU
There may be another copy of that Sandia manual here, and if Ira has fifty bucks, he can have it
if you want to sell your pseudoscience crap, do it on e-bay or amazon

more to the point, if you have a published "manual" that is used by Sandia National Labs you would be able to prove it with at least the ISBN
(do you even know what that means?)

or you would be able to link/reference it with more than just a claim

gkam
1 / 5 (5) Oct 27, 2016
Yeah, apparently in the world of the sniper who calls himself "Ira", lying is the norm.

Got the fifty bucks?
gkam
1 / 5 (5) Oct 27, 2016
The course was copyrighted by me. I did all the drawings, text, setup,and printing, and sent it out for binding. A lot of it was based on the national power quality course we wrote and presented all over the country for the Electric Power Research Institute.

What did you do in the electrical power field? Blow a fuse?
Captain Stumpy
4.2 / 5 (5) Oct 27, 2016
@STOLEN VALOR LIAR-kam superNSAspy
The course was copyrighted by me
so?
what does that have to do with it?

my wife has a lot of copyrighted material - it also has an ISBN
the ISBN is important - do you even know what that means?

.

.

so where is your ISBN?

that would be a way that someone (anyone) can validate your claim of having a published copyrighted manual that really exists

so either post the ISBN, link to the manual on some site that sells books or STFU

gkam
1 / 5 (5) Oct 27, 2016
Oh, stop it. Outgrow it.

You got mad when I berated the draft-dodging cowards who sent our sons and daughters into the Bush Wars, trying to twist, distort, and pervert it into an attack on my fellow servicemen. I made it clear they were professionals doing their job, a nasty one so needed by the folk hiding, who know they have no power themselves, so they get off by having others punished.

Yeah, I also taught the electrical engineers going to Alice Springs, and the installation teams from Cray Research back in the days. Accept it.

Save your disgusting attacks.
Arthur_McBride
5 / 5 (4) Oct 27, 2016
This a very entertaining discussion. And I really hate to interrupt the flow, but I do have two questions if you don't mind.

@ gkam. What does your first comment have to do with this particular article? As Uncle Ira pointed out, this is an entirely different method of extracting information than what you are alluding to.

@ Uncle Ira. I really have to know. What is this "( wearing a silly looking pointy cap with stars and moons on him)" all about? You wrote it twice but I am missing something. Man, that is just plain wicked weird.
gkam
1 / 5 (5) Oct 27, 2016
Arthur, my comment was in concurrence with the ability to use audible keystrokes to extract information from keyboard use. It shows the idea was around a long time ago. Sandia knew about signals in the powerlines a few decades ago, when I and another friend did the course there.

Ira refers to my many decades-old website with a drawing made by a customer who called me a Wizard.
Uncle Ira
4.2 / 5 (5) Oct 27, 2016
Ira refers to,,,


Cher, maybe you should let Ira-Skippy answer for his self. Otherwise you might get it wrong like you did this time.

@ Arthur-Skippy. How you are Cher? I am good, non too bad today, thanks for asking.

The silly looking pointy cap thing is just something I been doing on the interweb for years and more years. See here is what it is. When the extra goofy couyon comes around taking their selfs too serious, I like to pass out a "silly looking pointy cap" for them to wear. Like when the teacher puts pointy cap on a moron and makes him sit into the corner for a while. Fool's caps or dunce's caps, you understand?

Well ol' glam-Skippy started poking at me and earned a silly looking pointy cap from me. But lo it and behold it, he already had his own. A silly looking pointy cap with stars AND moons on him. See him here: http://www.kamburoff.com/

Oh yeah, I almost forget. That don't really instill confidence in the consulting you might get, eh?
gkam
1 / 5 (5) Oct 27, 2016
Arthur,

While you are there, look into the interesting current transformations caused by electronic devices in delta-wye transformers.

That website was done decades ago, when people were still inventing them, so it is not refined. All my work was from word-of-mouth, and I got the website for a stable email address, back in the early days of dial-up, when companies were buying out each other.
Arthur_McBride
5 / 5 (4) Oct 27, 2016
@ Uncle Ira. Thanks for the explanation. You do have a way with words.

@ gkam. Things changed a lot in 30 years, you really should try to update it. Why or how did you let people like Uncle Ira know how to find a webpage that you use to do business on? Surely you could see his "take" on it coming.
Captain Stumpy
5 / 5 (4) Oct 27, 2016
@STOLEN VALOR LIAR-kam
Oh, stop it. Outgrow it
so you can't produce the ISBN number?
is it because you don't have one or you don't know what it is?

this demonstrates yet another fail on your part, so let me educate you about reality and publishing

the ISBN is the ten digit (before 2007 - 13 digits after, but originally 9 digits from 1966-'70) "International Standard Book Number" all published anything gets one of these, and it can differ between formats (an e-book will have a different ISBN than a paperback, etc - reprints excepted)

so the fact that you don't have an ISBN tells us that you essentially made a crayon drawing and scribbles mimeograph in your basement and you expect us to accept it as an actual manual for something

not how reality works, & a real engineer, real MS in STEM or educated person would know that

so what you are doing is making sh*t up again and hoping no one will question the authenticity of your lie

too late!
optical
Oct 27, 2016
This comment has been removed by a moderator.
Captain Stumpy
4 / 5 (4) Oct 27, 2016
@STOLEN VALOR LIAR-kam
a drawing made by a customer who called me a Wizard
you mean a GIF that literally ripped off the idea from clip-art?
https://www.googl...clip+art

i am more surprised you aint been sued for copyright infringement.. oh wait, that would require a volume business to your website other than the PO people whom you've repeatedly argued with

i guess the fact that you're being ignored speaks volumes, eh?
Captain Stumpy
3.4 / 5 (5) Oct 27, 2016
Use virtual keyboards, if you feel insecure with your family.
@zeph
not sure that would work either, all things considered

so long as there is a means to hear (microphone or otherwise, now that we know you can use a camera to "see noise" - http://people.csa.../vidmag/ - also see vid below) then there will be a way to track your keystrokes. especially if certain distances are known (like the distance between each key, the microphone etc)

https://www.youtu...OucXB4a8

Uncle Ira
4.2 / 5 (5) Oct 27, 2016
@ Captain-Skippy. How you are? I am good me.

you mean a GIF that literally ripped off the idea from clip-art?
https://www.googl...clip+art
You mean there are that many glam-Skippys running around with silly looking pointy caps? I wish I owned a cap factory me.
Captain Stumpy
3.7 / 5 (3) Oct 27, 2016
I wish I owned a cap factory me
@IRA
i know, right?
perhaps you can sell them to the northerners and californians that visit your neck of the woods... call it the "certified engineering wizard" hat, or something

tourists soak that crap up!

we sell them rocks on strings and call it weather stations - made a veritable fortune last summer

https://41.media...._400.jpg

LOL

PS- that aint my rock, but it's an example of the stuff tourists are willing to buy

optical
Oct 27, 2016
This comment has been removed by a moderator.
Uncle Ira
4.2 / 5 (5) Oct 27, 2016
Like I say, it does not instill a lot of confidence in the consulting you are about to buy,,,, even if it is free advice with a double your money back guarantee. Looks like the interweb page for the kid's birthday party supply store.
Captain Stumpy
3.7 / 5 (3) Oct 27, 2016
we are talking about situations, when the attackers cannot use the cameras
@zeph
did you not watch the video i linked?

it didn't have line of sight to the person, it actually video'd things like plastic tree leaves and then got sound out of it...

that is why i linked it - you don't need to "see" the keyboard, only see something that vibrates to get sound. hence the title of the video: The Visual Microphone: Passive Recovery of Sound from Video

https://www.youtu...OucXB4a8
gkam
1 / 5 (5) Oct 27, 2016
Arthur, you can see the depth of thought by the comments of those two. Wait until "otto" starts with the filthy language.

Meanwhile, for fifty bucks, Ira can have a copy of the manual, or another course of mine, . . . ASD's perhaps.
Uncle Ira
4.2 / 5 (5) Oct 27, 2016
Arthur, you can see the depth of thought by the comments of those two.

Well at least I was deep enough to know that Sandia National Labs and Livermore Laboratory would not need to go and hire a person with no engineering degree, no engineering license to come in and teach them about power harmonics. Or security for that matter. Choot, you can't even fix up that sophisticated inteweb place you got and you going to teach all those Electrical Engineers, Computer Engineers and PhD's?

Come on now Cher, even you got to be smart enough to realize how goofy that sounds? On the second thought, maybe you are not.

Wait until "otto" starts with the filthy language.
He is not nice like me but he grows on you.

Meanwhile, for fifty bucks, Ira can have a copy of the manual, or another course of mine, . . . ASD's perhaps.
Cher, I seen your work. Now if he is as goofy as the interweb page, I would take a peek at him, but I am not paying unless it is extra stupid.
Captain Stumpy
3.7 / 5 (3) Oct 28, 2016
Why or how did you let people like Uncle Ira know how to find a webpage that you use to do business on?
@Arthur_McBride
he was making arguments from self perceived authority and figured that if people thought he was an engineer that they would simply accept the arguments given without requiring evidence for the claims

essentially it was a bluff - the "i'm better than you, so you must believe what i say" argument

he was very wrong

especially considering he made some very blatantly false claims (as defined here: http://www.auburn...ion.html )

many tried to warn him, especially about internet security and the stupidity of releasing personal information on a public forum that isn't controlled or moderated

but we're all idiots and no one is as great as the super-spy-uber-engineer-combat-veteran-teacher g!
[hyperbole, obviously]

LOL
gkam
1 / 5 (5) Oct 28, 2016
I see we are still bothered by the personal attacks from the anonymous snipers too scared to reveal their real names. I am real, and use my real name. I assumed this was a more professional forum, with moderation to limit the pubescent comments and personal attacks of the snipers.

I am deeply disappointed in this forum for being run by high-schoolers or others with adolescent character, permitting those personal attacks, despite their "rules". There are no rules here, just a public bulletin board for cranks.

I will "report" this post, hoping we have a "moderator" who will have the guts to "moderate" this forum. Do they really think interested and intelligent folk will put up with the continual arguments and personal attacks? Or do they not care?
Captain Stumpy
4 / 5 (4) Oct 28, 2016
@STOLEN VALOR LIAR-kam
I will "report" this post
sure!

while you are at it, perhaps you should report all your other posts for spreading hate and intentionally lying because you still haven't actually produced the ISBN for your "published manual"

LMFAO

Do you really think interested and intelligent folk will put up with your continued lies and intentional misinformation?

reported, per your own request
gkam
1 / 5 (5) Oct 28, 2016
Did you look up what goes on at Alice Springs? It is a communications point for our spy satellites. They were very interested in techniques to protect the information gleaned from being detected through powerlines. Look up TEMPEST and find out how some of it is done.
Captain Stumpy
4.2 / 5 (5) Oct 28, 2016
@STOLEN VALOR LIAR-kam
Did you look up what goes on at Alice Springs?
did you look up what ISBN means?
did you bother to note that you should have one?

.
yeah, didn't think so

so again, you made a claim
I sold about seven or eight copies of my Power Quality manual to the Librarian at Sandia National Labs
that would mean there is a way to classify the manual - but i don't expect you to be familiar with library classification systems

however, i do expect you to be able to do basic research considering all your zillions of claims of professional sh*t here

and as for what Alice Sprigns does - what does that have to do with the price of tea in China or your claims, for that matter?
NOTHING
not a da*n thing

& before you make the claim that your bullsh*t manual is "classified" - even that material has an ISBN (or equivalent nomenclature for historical material)
http://www.dss.mi...5220.pdf
gkam
1 / 5 (5) Oct 28, 2016
Give up your need to punish those who got you angry. It came from your own refusal to admit what I really said. Let's get back to the topic, shall we?

At Alice Springs our intelligence agencies are seriously concerned about security, and they sent their engineers to our classes for it. I am sorry you do not understand the field, but you apparently do not.

Did you look up TEMPEST? I can explain it to you, but it will take some time to go through the magnetic and electric field effects and how they can be tapped/detected.

But the technical course we gave was not classified.
Captain Stumpy
5 / 5 (3) Oct 28, 2016
@STOLEN VALOR LIAR-kam
Let's get back to the topic, shall we?
1- you took it off topic with your idiot narcissistic claims without evidence

2- requesting the ISBN *is* on topic as it directly substantiates or refutes your claim - in this case, your attempted redirection means it proves you're a liar yet again and therefore refutes your claims above, including but not limited to your references to past glories
they sent their engineers to our classes for it. I am sorry you do not understand the field
right
if i am so ignorant, why is it that you are the one distracting, backpedaling and refusing to actually validate your claims?

if they sent engineers to your classes, they would have reference material, which has an ISBN, which one could then research (and if it's classified, all you get is a title and some main authors, but it is still listed and able to be researched)

but your crap isn't even classified, so... why are you not able to produce evidence?
gkam
1 / 5 (5) Oct 28, 2016
Give it up, Trumpy. If you want a copy, I will send one, after the submission of your fifty dollars. You can continue to invent charges and situations, but like everything else, you are in over your head.

Back to the topic.
Captain Stumpy
4.2 / 5 (5) Oct 28, 2016
@STOLEN VALOR LIAR-kam
If you want a copy, I will send one, after the submission of your fifty dollars
1- until you can prove that it is an actual manual that can be validated with an ISBN... you are lying about it's existence

2- begging for money to prove you're legit? did you get that from reg mundy? http://sci-ence.o...-flags2/

3- why would i pay you for something that doesn't exist? and why pay you at all when i could get it for free off your own computer?

You can continue to invent charges and situations, but like everything else, you are in over your head.

unless you can provide at least *some* evidence, you're simply lying and attempting to get attention

Not going to keep reiterating that one - you can't prove it exists at all, whatsoever
period

and you still can't

so feel free to attempt yet another distraction and get the last word in

i will simply downrate and report it as spam/pseudoscience and phishing/begging for $$
Captain Stumpy
4 / 5 (4) Oct 28, 2016
@STOLEN VALOR LIAR-kam
post script - because you can't do homework, perhaps you should know that even a classified doc/manual will be labeled with the ISBN as well as other nomenclature due to
(42 U.S.C. 2011-2286) (42 U.S.C. 2011 et seq.), the National Security Act of 1947, as amended (codified as amended in scattered sections of the United States Code) ..., and the Federal Advisory Committee Act, as amended (5 U.S.C. App. 2) (5 App. U.S.C.)
all of which started long before your birth and adjusted from the more "modern" Atomic Energy Act of 1954 as some of the history is noted in Executive Order 12829

all that is reference material you can research and read for yourself - if you can learn to read

i know of it b/c unlike you, i actually have experience in not only classified material, but also in the military and gov't regulations, so i actually know where to look

feel free to provide refuting evidence if you can
[snicker]
gkam
1 / 5 (5) Oct 28, 2016
Well, gosh, if it got an ISBN number look it up. I did not apply for one. It should be about power system harmonics. It was over 15 years ago, so look back then. We were ahead of most folk in those days.

But your silly attempt to obfuscate the situation out of spite is adolescent.

You had a classified clearance? Did I send you the copy of my Crypto clearance yet?
Captain Stumpy
4 / 5 (4) Oct 28, 2016
@STOLEN VALOR LIAR-kam
It was over 15 years ago, so look back then. We were ahead of most folk in those days
should have read my references and links - they started using the ISBN in the 1960's, you idiot

2- how were you "ahead of most folks" when you can't even find basic information that was public knowledge as far back as 1954?

your silly attempts to obfuscate the issue and hide the fact that you're blatantly lying about your "super manual" are glaringly obvious
You had a classified clearance? Did I send you the copy of my Crypto clearance yet?
ROTFLMFAO

like that means anything?
other than you're still trying to obfuscate and redirect from your proven lie and blatant stupidity

& about security clearances - mine is far higher than yours, so don't bother

your distraction failed - again

gotta go, i have a real life and you don't
plus, you still haven't actually provided ANY evidence at all, other than your claims

reported
gkam
1 / 5 (5) Oct 28, 2016
Show me your clearance, and I will send you mine. I think you are a liar, and have no experience whatever. You are too scared to reveal your identity, after all the lies and abuse sprayed all over this forum.

Let's get off your need to attack the decent folk, and back to the topic of electric/electronic surveillance, which was my field. What did you do?
Uncle Ira
4.2 / 5 (5) Oct 28, 2016
Did I send you the copy of my Crypto clearance yet?


https://www.youtu...-6MUz06w
gkam
1 / 5 (5) Oct 28, 2016
Sorry, I do not take your bait, "Ira". I watch none of your videos or whatever they are.

If you would like to discuss the topic, let's do it. But keep your adolescent humor in school.

Thanks.
Captain Stumpy
4 / 5 (4) Oct 28, 2016
@STOLEN VALOR LIAR-kam
after all the lies and abuse sprayed all over this forum
1- if you could prove this you would have sent your "lawyers" after me

2- still no evidence or proof that you published anything (excepting your "professional" web-page - satire and hyperbole intended)

3- you still haven't provided the evidence to validate your own claims being challenged in this thread

4- you are still attempting to redirect the conversation because you still can't provide evidence

5- reported for baiting, begging for money, phishing and trolling with pseudoscience and blatant lies

.

.

.


https://www.youtu...-6MUz06w
@IRA
awesome - i swear they were following gracie around to get material

and actually relevant to the discussion, too!
THANKS for that!
LOL
TheGhostofOtto1923
5 / 5 (3) Oct 31, 2016
Hey there little monkey
Give it up, Trumpy. If you want a copy, I will send one, after the submission of your fifty dollars
Post it on your little monkey website so that everyone can see it.

Unless you are SCARED.

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