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Researchers Find Way To Zap RSA Algorithm
alphadogg writes "Three University of Michigan computer scientists say they have found a way to exploit a weakness in RSA security technology used to protect everything from media players to smartphones and e-commerce servers. RSA authentication is susceptible, they say, to changes in the voltage supply to a private key holder. While guessing the 1,000-plus digits of binary code in a private key would take unfathomable hours, the researchers say that by varying electric current to a secured computer using an inexpensive purpose-built device they were able to stress out the computer and figure out the 1,024-bit private key in about 100 hours – all without leaving a trace. The researchers in their paper outline how they made the attack (PDF) on a SPARC system running Linux."
...whether interrogating a human or a computer, apparently it is a simple matter of voltage.
The only thing the article "ads" to the summary posted here is a pretty splash screen, which in my case tried to sell me SQL Server.
Machines where software can alter the CPU voltages and clock speeds for "overclocking" purposes may be especially vulnerable to this attack. "Advanced power management" may also offer an attack vector.
Also worry about Intel's Nehalem architecture, where there's a small CPU dedicated to power, clock, and thermal management. Access to that allows detailed control over power.
...electronic torture?
We can just declare this method in violation of the computer's rights and solve the problem easily!
In what kind of scenario would you have access to the PSU of the server you attacked? Private key servers should not be directly accessible after all.
Rather than apply electrical current to a key holder, wouldn't it be easier and cheaper to apply a $5 wrench?
No, reasearchers find side-channel attack on SPARC CPU (which requires elevated access, anyway).
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
hackers these days are seriously sick, not long ago one guy dissolved chips and listened in on instructions right on die
now this, just take a look at that paper
sure the principle is simple, create condition that causes errors and incidentally more of the bits you have guessed the less errors you have etc etc etc
but seriously people who figure these things out and make them work... i question their sanity, brilliant but you have to be a mad scientist to achieve these things
In what kind of scenario would you have access to the PSU of the server you attacked?
E.g. Hosted data center
Probably much more threatening(though, frankly, that pleases me) to DRMed embedded systems and similar gear that is supposed to be "secure" vs. its immediate environment; but is also in the hands of the public in huge quantities.
Yeah, if I can break into your datacenter and clamp some crazy widget onto the (presumably multiple) lines supplying your server's PSUs, a clever voltage attack is not the biggest of your problems.
If, on the other hand, you can guess the private crypto keys out of a DRMed PMP just by clipping a 15 dollar device from some shady mod-chip vendor to the recharging port and waiting a few days, heads will roll. There are a lot of devices these days that are designed to keep keys secret from the owners of the hardware. Particularly for common ones, voltage attack devices might well become fairly common advanced hobbyist and/or grey market items...
This attack is relevant when you are trying to extract the private key of something like a TPM, in order to defeat the DRM protections it is trying to provide, or decrypt the drive whose key it is holding.
DRM, smart-cards, cable/tv access boxes, media players, stolen laptops, etc
Probably not e-commerce servers exactly, but you never know depending on the physical security of your datacenter. And with DRM, of course, the purpose is to lock you out of equipment to which you have physical access.
"I assumed blithely that there were no elves out there in the darkness"
This is just a fault injection attack. People have been doing similar things to block ciphers for years, it is not a mathematical weakness, just a side channel attack, and an active one at that. Cool that they did it against RSA, but not really headline news...
Palm trees and 8
If someone has physical access to your machine, then you have already lost.
Im a gamer, not a grammer major. This post is full of spelling and grammer mistakes.
...except for the empty bags of cheese puffs, Rockstar cans, and several bottles of "lemon gatorade", no one would suspect that they had been there.
Sadly, most DRM-crippled hardware isn't going to have the private keys inside. For example, the PS3 and Wii will only have the public keys in the hardware so that they can check signatures on code. The private keys will be on hardware somewhere inside Sony and Nintendo, and presumably carefully guarded from unauthorized access.
GCHQ Quantum Insert installed. If only our tongues were made of glass, how much more careful we would be when we speak
When the 'server' is a chip on a smart card and the 'PSU' is your POS terminal.
A similar sidechannel attack might be usable to extract such information though.
retrorocket.o not found, launch anyway?
Depends on what the DRM is trying to protect. Music players, video players for downloadable content, and basically anything where the content isn't tied to a physical object like a game disc will need a private key of some kind to encrypt the data on their volatile storage. While most of this will probably be done using symmetric encryption, you still need some way for the server that hands out the content to prove that it is a real device and not an emulated device, and that's normally done with a locally stored private key.
It's an implementation on specific hardware that was broken. Not the first time, nor the last. If the *algorithm* would have been broken, now *that* would have been news!
Ubi dubium ibi libertas: Where there is doubt, there is freedom.
Kinda reminds me of the TrueCrypt attack that made a splash a couple of years ago in which the attacker can compromise an encrypted partition by obtaining possession of the host hardware right after a power-down, getting inside the chassis and spraying down the RAM DIMMS with an inverted can of air so as to cool them down to slow the entropy of the down-powered chips; the attacker then has to create and analyze the leftover ram images with his own hardware and pull the encryption key out of that mess. As the Mythbusters would say: plausible? Yes. Practical? not really. I guess if you think you're in possession of some pretty valuable data you'll go to lengths.
Python: 'And then suddenly you have a language which says "we're all stuck with whatever the whiniest coder wants".'
In what kind of scenario would you have access to the PSU of the server you attacked?
I don't know, how about a world where you've arrested a political dissident and you want to obtain his/her private key, and he/she refuses to hand it over?
Rubber hose.
To the back of the thigh.
10 seconds.
100 pesos.
Since when did slashvertisments start to include BDSM offers?
I am Slashdot. Are you Slashdot as well?
Great, another 'if you have physical access to the key, you can get the key' methods.
Look, 'stressing' the computer for a hundred hours while screwing with the voltage is going to get you noticed if its a key important enough for to use this method to do it. I can go to your PC and steal the contents of the entire drive without leaving a trace, but you're probably going to notice when I move you out of my way so I can put in a boot cd and external drive to copy the data to.
Practical value: 0
Research value: 1
Geek Cred: 11
Priceless, or rather, worthless.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
Just use Social Engineering
TPM chips and certainly high end smart card chips are protected against this kind of attacks using the power source. You certainly cannot get a Common Criteria certification if you don't protect against these kind of side channel attacks. Of course, for consumer CPU's there' no CC certification or protection measures like these.