Slashdot Mirror
Nikon's Image Authentication Insecure
silanea writes "Elcomsoft claims to have broken Nikon's Image Authentication system which — apparently only in theory — ensures that a photograph is authentic and not tampered with through a digital signature. They were able to extract the signing key from a camera and use it to have a modified image pass the software verification, rendering the rather expensive feature mostly marketed to law enforcement all but useless. So far Nikon has not given a statement. Canon's competing system was cracked by the same company last December."
Whew - I've always hated having to wear a ski mask when I "work". Now I can just claim image tampering.
He's getting rather old, but he's a good mouse.
Not like anybody would've expected that ...no way ...
With this secure authentication feature, we will finally know which of the photos in the 'Celebrities' sections of porn sites are real!
This is great news, because now people will be able to cast doubt on images when there is cause to instead of being told "it's not possible it's a fake, it's signed". You know that if someone cracked it publicly someone else (probably many someone else's) have cracked it in private, and have kept around the ability to forge photographs in case of emergency... that ability is now reduced.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
I'm getting a serious case of déjà vu...
Requiem for the American Dream
Just take a picture of the photo-shopped image with your Nikon camera. Bam! That was sure hard to crack.
So a picture is still worth a thousand words, but 999 of those words may be a lie.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
or face what your comic style textbook deems, a very bad ending. at once mind you.
Where every local implementation of DRM has been broken. Sure, they could require a working internet connection for every picture taken, but I'm pretty sure even the laziest corporate-boot-loving shopaholic would draw the line at buying a camera with such a "feature".
Those who can, do. Those who can't, sue.
Has there ever been a case whose outcome depended on the authenticity of a digital image?
Yes
Their press release can be found here:
http://www.elcomsoft.com/nikon.html
The press release does mention that you have to extract the key from the camera. If this is relatively easy then the system is totally broken. If it is not, you could create some kind of revocation list - but it would be the equivalent of a sloppy patch. Security is hard to accomplish, it does not surprise me that a camera manufacturer fails hardware protected signature creation.
I think the authorities will still say "it's not possible it's a fake, it's signed" and it'll be up to the victim (or the victim's lawyer) to know that the signage has been broken.
The last time I was stopped in a speed trap (on motorcycle), I knew it was coming up (they always put a speed trap in this particular construction zone on weekends because people ignore the temporary "35" signs 'cause there's nobody working on Sunday, but I digress) and had slowed way down before taking the turn, but was waved over anyway. I was pretty sure he'd tracked the (obviously faster) car one lane over instead of me, and said so. He said "the gun can't be wrong, I had a firm lock on you." I can see the stupid radar gun in his hand right there, and it's not like there's a scope on it, or even if he actually had me in crosshairs, that it could tell the difference between a slow moving object in the foreground and a much faster object in the background. I maintained that he could not possibly have locked on me, because he would have read 33 MPH, which is what my speedo was displaying at the time. I said it obviously had "locked" on the car that passed me shortly after the corner. The cop said that this was impossible, radar guns don't make that kind of mistake.
Well hell, there's a huge body of evidence that radar guns make "mistakes" all the time. I laid out exactly how the error could have occurred, he continued to insist that the gun can't make mistakes. I finally said "ok, whatever. We'll see what the judge says." He went away, talked to his cohorts for awhile, came back and issued me a "verbal warning", let me go. Now, I strongly suspect that if I'd acted like I knew nothing about the technical details of radar guns, I'd have gotten a ticket.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Is this how those pictures are authenticated?
Disclaimer, I didn't RTFA.
Wouldn't each camera have its own signing key so all they could do is forge pictures from a single camera? They couldn't forge pictures from another camera without its key. Is there evidence of the key extraction left on the camera?
Photographic film does not have this problem, though their prints can. Film contains a holographic image, albeit not like the dramatic ones you generally see. It has always been impossible to fake it.
and what stops me from taking a real photograph of a fake photograph? snap, photoshop, print, snap.
no one cares if the "photograph" is real or fake. We care if the content of that photograph is real or fake. So unless they digitally sign the universe to match the photograph, they've done nothing.
not to mention, have people forgotten that there are other ways to fake a photograph than with photoshop? Ever heard of actors, sets, studios, and lighting? Glass paintings, forced perspective, and dry ice?
again, congrats on trying to say that no one used photoshop since the last snap of the camera. That's really not difficult to keep true.
Curious if these guys violated the DCMA in the course of doing this? Sounds kind of like the printer cartridge manufacturers that reverse engineer the code on printer cartridges intended by Canon, HP, et al to ensure that only OEM-branded cartridges can be used.
The 105mm f/2.5 causes me forgive any mistakes Nikon may have committed. And I want it that way.
Good on you for standing up for yourself! I know that police like to use Gatso 24 AUS-series doppler radar units around the 40kmh school zones in Australia.
The problem with this is that the Gatso operations manuals as well as the police operations guidelines say that these units are not to be used in zones signed less that 60kmh (they're unreliable at low speeds) except that nobody in the public would know this or even consider questioning them over it. Most people wouldn't even bother to ask the officer what they've set the cosine correction factor to, or ask to see the calibration report that they must fill out at every location they setup (every time they setup).
I don't understand why you weren't tazered?
Sleep your way to a whiter smile...date a dentist!
You're lucky he didn't give you one just for being sure of yourself / mouthy / "trying to get out of a ticket".
It was a few years ago...
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I wasn't "trying to get out of a ticket". I wasn't guilty of the infraction of which I was accused. Have we really gotten to the point where professing innocence is a sign of guilt?
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I think Elcomsoft is too strict and too harsh versus the digicam vendors. It is not possible to design a secure device at all, if the private key is stored in the device. An adversary advanced enough will have superb lab gear, including a scanning tunneling electron microscope and can sort through the integrated circuits atom by atom, if necessary. The key will be retrieved eventually.
Even if that does not work, the attacker could monitor power consumption or other side channel signals to deduce the keys. It is not reasonable to except a commercial digital camera to have TEMPEST features en par with a KH-11 spy satellite!
I think photo authenticity should be provided by special digicams, which also shoot a 135mm common film frame, in addition to the higher quality CCD/CMOS digital image. Chemical based roll film megative contains an almost infinite amount of information, so experts could you use it determine or exclude fakery.
Question marks are for questions?
(1.21 gigawatts) / (88 miles per hour) = 30 757 874 newtons
And yet corporations the world over are clamoring or have made this type of hacking, even on your own bought stuff, illegal.
This is what you get for implementing your own crypto. My suggestion to both Nikon and Canon is to include an ISO-7816 ID-000 port in their cameras (more commonly known as the SIM slot in mobile phones) and support one of the well-defined standards for public key operations on smartcards (PKCS#11 for example).
This means they have far less pressure to build a robust cryptographic system as it is built-in to the many, many compliant and certified smartcards out there in the market. Instead they can concentrate on the much simpler problem of using the crypto functions properly.
The major added benefit is that customers with strict security requirements (i.e. law enforcement) don't have to trust the crypto engines/key storage mechanisms developed by their camera supplier. They can put their own (trusted) smart-cards in the camera as simply as swapping a SIM in a mobile phone. For customers that don't want this, they can simply trust the default smartcards supplied with the camera.
only the last part of your argument was correct, "let see what the judge says".
The racially ambiguous (not quite white, if you prefer) do not argue with cops...
Cheap storage VM.
You are my hero.
Yes. Like the one you just asked.
I wonder how many convictions (especially for redlight and speed cameras) have been made on the strength of the "unbreakable" signatures?
If none, then why do police waste their money on this? If not none, how many do you suppose will get even a cursory judicial review?
It is well known in the UK that radar and lasers are not an accurate way to measure speed. In fact speed cameras only use it to decide if they are going to take a photo or not, the actual speed measurement being based on the distance travelled between two photos taken a fixed time apart. That is what the white lines on the road are for.
When they do use radar or laser measurements you can almost always get off in court. Many people find that simply pointing the speed gun at the judge and showing him the readout that states he is doing several MPH is enough, but if not you can probably get them on one of the following:
- Were you the one actually driving?
- Can they produce a valid calibration certificate for the gun?
- Can they show the operator was properly trained on that model?
- Can they demonstrate that it was aimed properly and didn't reflect off a non-flat part of the car?
They just rely on people either not going to court or not knowing how to properly defend themselves.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC