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Breaking RSA Keys by Listening to Your Computer
An anonymous reader writes "Adi Shamir and crew gave a talk on preliminary results in extracting a private RSA key
just by listening to the computer!. Similar to power analysis and LED leakage, this is a non-invasive, side channel attack that may have applications to tamper-resistant systems. It appears to be related to noisy capacitors on the motherboard, an effect which has been observed when CPU power saving is enabled on laptops."
Investigations are an important part of the justice system. Though the tenet is "innocent until proven guilty", it's only possible to prove someone guilty by means of an investigation.
By encrypting your data, you are bringing unnecessary suspicion upon yourself. I wouldn't be surprised if the FBI's powers are enhanced to include surveillance of you and your data.
I have been pwned because my
Does anyone know the range of how far you can be away from the computer to hear the sounds? The proof-of-concept website just seemed to be "look, here are pictures of computer operations... in sound! Yay!" without enlightening us on any details.
Twenty years ago at Bell Labs one of the speech machines (an SEL with homebrew audio i/o) had output to loudspeakers that went through unshielded speaker wires that ran past the CPU, so if you weren't playing anything back the speakers played back CPU noise. We could tell what stage a compilation was at by the noise that came over the speakers.
I usually get this on my own setup a P4b-266 w/1.7(oc'd to 1874), but only after a reboot; and only do you hear it on re-init's prior to loading windows(pick a flavor) or BSD. Not when the machine is running.
I'm thinking that it's the little critters getting just abit too hot, I found that increasing the airflow and cooling everything down by a couple of degrees seems to make the noise go away. Unless...it's in the winter...in which case...the house is more then cool enough and you don't have to worry about it. heh.
The boards are good, but my man...were already looking at the operational product end for these boards and it's been two years since they came out. It took intel 6mo to come out with the 533, then the 800's. I kick myself in the ass everytime I think on that...and and buying a AMD next time around; I can get a proc and board twice the speed at half the price for what I paid for this one.
Om, nomnomnom...
If you go to the site of the DPA attack,Cryptographic Research, you can see that they have already have patents on Systems to protect against these kind of attacks. So it's not like they have developed anything (I don't know if they have) but you can already pay them to get protection from this kind of attack! yay!
Even at a 96 kHz sampling rate, the maximum frequency that can be sampled is 44 kHz. How could one hope to extract a certain few bits from a recording when the CPU's instruction throughput is many times that? Most of the information that would need to be examined wouldn't make it onto the recording. Correct me if I'm wrong, but it seems Nyquist leaves this idea dead in the water.
If you really want to do some acoustic evesdropping, listen to the keyboard. It's got a much larger signal to begin with (from across the room, instead of having to paste your ear to the computer case.) Since there are always slight mechanical differences between keys on any given keyboard, I would think that the sound spectrum would also be slightly different. Being able to always listen in on the same user would also help, since most people are somewhat consistent regarding which finger they use on which key. (Evesdropping on people who were smart enough to take a touch-typing class in high school is also a big plus.)
Assuming you could discern between the acoustic fingerprint of 100 different keys, then it's just a matter of figuring out which sound goes with which key. It's a simple substitution cypher, which are almost trivial to break.
Sneak your cell phone into your boss's office, set it to silent mode and plug in a headset so that you can set it to auto-answer when a call comes in. Then, while your boss is busy typing dirty notes to his mistress, you call your cell phone, start recording it, and presto, you've got a keylogger without ever having touch his computer or the software on it. Then, at your next performance review, you convince him to give you a hefty raise.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
Is this similar to the noise heard when using an onboard sound card? On my laptop when plugged in to the mains, a distint hiss/buzz/rumble comes out the line-out jack. It changes when moving the mouse or accessing the hard disk, or when the CPU is under load.
It seems that this is a more reliable method for finding a key than using a microphone, but, of course, it does require physical access to the computer.
PocketGamer.org - For the gamer on the go!
The most common thing I've found to induce audible noise (I use a SB Live, and can easily hear this with even cheap speakers) is to demute the sound card inputs that aren't connected to anything -- like CD audio and whatnot -- and then start moving my PS/2 mouse, which generates a fairly slow sequence of signals, producing a definite buzz. Video redraw also can do this -- dragging windows works well as well, and what's on the screen (oddly enough, lots of white areas seems to cause more of a buzz) has an impact.
It's really amazing how dirty a computer power supply is -- I also picked up a headphone preamp that fits inside a 5.25" drive bay, and can optionally run off the computer power supply. If it's running off the power supply, I get a *very* noisy signal that is affected by things like hard drive access.
May we never see th
R = Ron Rivest
S = Adi Shamir
A = Len Adleman
Having worked in telecommunications as well as consumer electronics and computing, I've played a lot :)
One of the more interesting things for fun was to poke around with a induction amplifier, you know, the "hound" in the fox and hound tone generator/ handheld probe that the phone guys use for tracing copper thru a building.
It is pretty sensitive and I've found many fun sounds by waving it around in various analog and digital equipment, it kinda gives a unique viewpoint. Used in different locations in a PC it picks up various interesting sounds that are very different according to what the system is doing, and where you are probing, memory, chipset, io/chips, cpu etc. Never found it very good for troubleshooting PC's, but lots of fun!
Also, I think the sounds you can hear around running electronics is partly caused by sympathetic viberation induced in the air molecules by high frequency energy changes happening, especially on the buses where there are long runs exposed, as well as perhaps by the caps, (?), could it be the aluminum in the caps is reacting to the energy field?, most of the round tall caps you see on a board are used on low frequency mainly power filtering applications.
I think your parent hit it on the nose. You're never going to "hear" individual bits. The computer processes at speeds that are fucking orders higher then the best sample rates known to man. The atoms of air just can't be excited that fast. They can't hold that type of information. Shamir is qualified, but that doesn't mean everything he works on is going to be a cryptographic holy grail. This is really interesting stuff, and there's certainly big potential here, but lets not kid ourselves about the possibilities.
The darkness... controls the music. The music... controls the soul.
I recall reading rumors of a blind fella who could play MunchMan on the TI-99/4 just by listening to the sounds in the background of the game.
While my experience is no where near that in-depth, I do remember that the computer made distinct sounds when performing certain tasks, such as reading GROM, initializing, running BASIC programs (I recall that some statements also have distinct sounds as well.)
Since then I have been able to detect certain sounds from my machines which indicate normal operations; to some extent I think we all do, just as we do with cars to "know" that something isn't right. And it's been pretty consistent through all of my computers: Commodore 64, 128D, Atari 800XL, various Amigas (amazing things heard by holding your ear to the A500 power supply,) many desktop PCs and notebooks. Even some console systems generate sounds under operation (an old NES on my shelf with a bad filter cap is good for this.)
I'm curious to know what correlations between design type, grounding, processor architecture, and other factors exist for this. Might be worth investigating like this chap did, should I find the time to do so.
How can you differentiate between computations , when the CPU is at 100% utilization all the time? :)
Well, to use the scientific term, "it depends". I've been thinking about this (like about ten thousand other crypto people) throughout the day. Certainly, Brumley and Boneh's attack will work (and probably better, because 1/44,100 is microsecond resolution): http://crypto.stanford.edu/~dabo/papers/ssl-timing .pdf
...
We do have more data than just time, too -- we have instruction profiles. If it's possible to absolutely know the input to the RSA signing function, and it's possible to alter that input while still knowing the (probably hashed) result, then you can get a set that looks like:
RSA(Known_Hash_1, Unknown_RSA_Private) = Known_CPU_Profile1
RSA(Known_Hash_2, Unknown_RSA_Private) = Known_CPU_Profile2
RSA(Known_Hash_3, Unknown_RSA_Private) = Known_CPU_Profile3
RSA(Known_Hash_N, Unknown_RSA_Private) = Known_CPU_ProfileN
So you're solving for Unknown_RSA, based on the differentials in CPU profiles. Not trivial, mind you -- but absolutely fascinating.
--Dan