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Almost 'All Modern Computers' Affected By Cold Boot Attack, Researchers Warn (cnet.com)
Security researchers have discovered a flaw with nearly all modern computers that allow potential hackers to steal sensitive information from your locked devices. CNET adds: The attack only takes about five minutes to pull off, if the hacker has physical access to the computer, F-Secure principal security consultant Olle Segerdahl said in a statement Thursday. Cold boot attacks can steal data on a computer's RAM, where sensitive information is briefly stored after a forced reboot. These attacks have been known since 2008, and most computers today have a safety measure where it removes the data stored on RAM to prevent hackers from stealing sensitive information. It's also not a common threat for the average person, since both access to the computer and special tools -- like a program on a USB stick -- are needed to carry out the attack. But Segerdahl and researchers from F-Secure said they've found a way to disable that safety measure and extract data using cold boot attacks. [Further reading: ZDNet] "It takes some extra steps compared to the classic cold boot attack, but it's effective against all the modern laptops we've tested," he said in a statement. Per F-Secure, there is no patch to address the new vulnerability just yet. For now, the firm recommends that you make tweaks to your system settings so that your computer automatically shuts down or hibernates instead of entering sleep mode when you close your screen.
If I have 5 min alone with system its mine. That is security the most basic security concept. "It only takes 5 min" I need less then that for most systems. Sigh. I dont understand how this is news.
you are already screwed by a litany of other potential vectors. That's why physical access control is so important.
Pull the hard drive, take home and decrypt at will. No known software or hardware patches have been released to fix this issue.
... When doused in petrol and lit on fire, all computers BURN. Thanks captain fucking obvious.
There is really almost no info here, so not much of an article. I suppose it is implying that you can do this attack when someone walks away, and when they return they are none the wiser. Or at worst think their laptop rebooted for some reason.
I will shred my adversaries. Pull their eyes out just enough to turn them towards their mewing, mutilated faces. Illyria
It involves cooling the RAM chips with some kind of refrigerant spray. So yeah, you need the computer you do this with to be right in front of you and powered on and logged into at least once by some user with a key you want.
Full disk encryption is what this attack defeats. Full disk encryption is really ONLY useful to stop someone with physical control of the computer from accessing your data. Also, the details I read made this sound like a relatively easy attack to implement if you've prepped your work area reasonably. Consider that anyone doing this has already stolen a computer - perhaps by breaking into a home or business. Then they must have a computer with valuable enough data to bother going after it. They aren't going to be going after my pc, and probably not yours. Maybe a politician, banker, or someone with proprietary corporate secrets.. say a fortune 500 exec. For that kind of value as a target, this is a simple attack - compared to other attacks that might be used on high-value targets.
Send a 'Drunken, tell off the boss' email from your biggest problem's desk. While they are at lunch, but late enough they could have come back looped.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
So an extra-cold boot, then.
This attack does not defeat full disk encryption. It allows access to your encryption keys if and only if the hard drive is already unlocked.
Saying this is a vulnerability is like saying that all safes have a vulnerability that when they are unlocked, anyone with physical access to it can get everything that's inside and, moreover, they can also with special equipment get access to the tumblers to determine what the combination was and even change it.
This is not a "simple" attack. It requires basically physically stealing the computer after it has been booted up and the encryption key password entered. So it's really a special case of rubber hose cryptography (threatening the person until they give up a password).
To protect yourself from this "vulnerability" you simply need to ensure that when you stop using the safe that you close it and lock it. Or, in other words, turn off your computer. Modern RAM will be degraded to the point where the key is unusable after about five seconds.
You need the SEV instruction/extensions specifically.
This could be easily fixed if the BIOS wiped/tested the whole ram after reboot. If i remember correctly, it might be as easy as adding a small module to the bios.
Any hardware disk encryption, and any use of a security module like a TPM chip, will keep the decryption key out of RAM even for the one minute the system may be vulnerable.
This is either incorrect or only partially correct. Hardware encrypted drives (at least the FIPS certified ones we use at work) are unlocked once and then remain unlocked as long as there is power to the system. Insert a USB stick, force a reboot, boot off the USB stick, and you have full access to the drive.
I'm not sure if the encryption keys are stored in RAM or in volatile memory on the drive itself, so sure, you may not be able to get the keys. But you can still clone the drive, so not having the keys is pretty irrelevant.
Long story short: even with hardware encryption, shut the damn thing down when you're not using it.
What kind of fool doesn't know where the cameras are? What kind of hell hole are you working at?
Here: Boss would have called 'shenanigans', but played along for a little while, to get people to lock their desktops. Later that same day. Unless he found person actually drunk.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
You haven't considered the case of "suspend", which the summary mentioned. When a laptop is suspended (and I think most are when they're not in use), encrypted disks are unlocked. And desktops are often left on when not in use. I think the GP is accurate: this attack defeats full disk encryption for most users.
A cat can't teach a dog to bark.
There really is no way to protect yourself if you let someone have 5 minutes alone with your system especially while it's still on.
all bets are off.
Again, you are ignoring the extremely common case of suspend. If the computer has been opened up after being suspended, it is fully logged in and running. That lock screen you see is just a UI. It is not indicative of the computer's state. (It would be possible to unmount encrypted storage during suspend, but I don't think any popular OS does that. Might as well just hibernate instead.)
A cat can't teach a dog to bark.