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TrueCrypt Master Key Extraction and Volume Identification
An anonymous reader writes "The Volatility memory forensics project has developed plugins that can automatically find instances of Truecrypt within RAM dumps and extract the associated keys and parameters. Previous research in this area has focused specifically on AES keys and led to the development of tools such as aeskeyfind. The Volatility plugin takes a different approach by finding and analyzing the same data structures in memory that Truecrypt uses to manage encryption and decryption of data that is being read from and written to disk. With the creation of these plugins a wide range of investigators can now decrypt Truecrypt volumes regardless of the algorithm used (AES, Seperent, combinations of algos, etc.). Users of Truecrypt should be extra careful of physical security of their systems to prevent investigators from gaining access to the contents of physical memory."
Don't people burn memory blocks any more? This is sensitive data handling 101.
Way too tedious (and requiring physical possession of the hardware after encryption passwords/etc have been entered!) for the modern NSA -- they'll just install keylogging hardware that communicates over radio frequencies and not the internet if they need your encryption key. Then, your hacked ethernet/bluetooth port will also send them image of your drive over RF or some other discreet channel. Who needs this!?!
While good to know these types of attacks exist, TrueCrypt's security model is still holding strong. http://www.truecrypt.org/docs/security-model
Given that we're in an era of low-cost portable devices (Raspberry-Pi, BeagleBoard, etc.), it would be really nice if TrueCrypt could implement a driver that passed data off to an external, open-source device for processing that held the keys in its own memory, and provided no other service than to perform the cryptographic functions and hand back the data. It would be slower, but at least then you don't have the keys in memory on a general purpose computer running browsers, java, flash, adobe reader, etc. etc.
Take one of those devices and attach a small screen to them and you could enter your passphrase using a keyboard attached directly to them, and use a keyfile on a flash stick plugged into the USB port too. The distro powering all of this could be minimal and audited.
Nothing that you mentioned would prevent someone from taking a memory dump of your machine.... With firewire, pci slots, or other DMA-capable hardware slots, memory can be captured with physical access and no user credentials required. With (root) user credentials, memory can be captured through projects such as LiME that are kernel modules that dump physical memory to disk or over the network.
A billion people not in your parents' basement?
hibernating is okay if you use full disk encryption as the hiberfil.sys will be within the encrypted filesystem.
The DMA part is not new, but several other aspects are: 1) Other tools only find AES keys, the new plugins find any algo that truecrypt uses as it inspects the truecrypt data structures in memory to find the values instead of scanning memory hoping to find a key 2) Volatility shows you files that were being accessed (along with their full path) inside the TC mount 3) All of it is automated for Windows XP through 8 and the server versions
Shut your machine OFF before you get to the border; don't put it to sleep.
I do not fail; I succeed at finding out what does not work.
The moral of the history: if you have sensitive encrypted information on your laptop, never travel on standby mode, always turn off or use hibernation over an encrypted file or partition
-a KEYLOGGER is an infinitely greater risk to the use of ANY encryption system, and keyloggers are trivially inserted into a PC via almost unlimited numbers of hardware and software methods.
-gaining access to the current RAM of a system is just about the most convoluted and 'expensive' method of a targeted attack. The contents of RAM, of course, are lost once the system powers down. If you are targeted, there are a million easier ways of gaining your password. Many simply use the placement of hidden cameras. At the other extreme, remote equipment can be used to recreate your screen content via EM radiation emitted by the display and drivers.
If Truecrypt is coded properly, it can attempt to keep the 'key' within the caches of the CPU only, and avoid 'write-back' on most processors. If RAM must be used, there are numerous obfuscating RAM usage methods that can prevent the key from living in predictable sequences of RAM bytes. However, you can assume Trucrypt is doing such as much as is useful. Truecrypt FAILS the moment the user is a LIVE (as in current Truecrypt user) target of a 1st class US intelligence operation. Gaining the password from a person who is still entering the password on a regular basis, when money is no object, and the Law is bent as is required, can be taken for granted.
The owner's of Slashdot promote stories like this for one reason- to DISCOURAGE as many people as possible from bothering with Truecrypt in the first place. If naive sheeple THINK Truecrypt is as compromised as the NSA back-doored products from Microsoft et al, they'll 'think' they might as well use the Microsoft or similar product, because of ease of use.
EVERY anti-Truecrypt story is NSA FUD. EVERY commercial encryption package, for instance, allows warrantless searches at the border to reveal the use of encryption, and allows the agents to strong-arm the KNOWN existing passwords from you. However, despite what the vile shills tell you here, used properly there is ZERO trace of actual encryption use on your laptop with Truecrypt, so the probability of warrantless hassle is reduced to as close to zero as you are going to get.
TruCrypt can be written to automatically unmount the 'drive' as the computer goes to sleep
It could, but it isn't. I was shocked to discover that my TC volume was still mounted after resuming from sleep. After all, notebooks get stolen, and that is why I have my passwords and SSH keys in a TrueCrypt volume. And notebooks are not normally shut down but put in sleep mode instead. So I discovered that the way Truecrypt worked made it's encryption quite irrelevant...
I fixed the problem on my Ubuntu notebook with a "tc-unmount" script in /etc/pm/sleep.d/ but I guess not many people do that. In Windows, I think there is a configuration setting for unmounting on sleep, but it was not enabled by default last time I looked.
So, while it may sound impressive that it is possible to extract the keys from RAM, it is usually unnecessary. The volume may simply be mounted and directly accessible, even after sleep.
It seems like the attack vector people are worried about here is "people get physical access to your machine while the key resides in RAM and extract it".
Could you program Truecrypt to maintain a continuous watch via a laptop's built-in webcam for the physical presence of someone at the keyboard (face detection, say), and upon detecting that the person has moved, dismounts the volume, overwrites the section of memory storing keys with random bits (to protect against "put the RAM modules in the freezer" attacks), kills the bulk of the Truecrypt software, overwrites it, and then kills itself? You could add other failsafes if you wanted, I suppose (based on the machine's microphone input, perhaps), but the idea is to have a dead-man's switch that will automatically dismount the partition and remove the keys from memory when Something Goes Wrong, so the keys are only around when you are actually sitting there working, and as soon as you aren't there, they are wiped.
> Users of Truecrypt should be extra careful of physical security of their systems to prevent investigators from gaining access to the contents of physical memory."
By investigators, do you mean government workers conducting industrial espionage?
http://www.washingtonsblog.com/2013/10/nsa-busted-conducting-industrial-espionage-in-france-mexico-brazil-and-other-countries.html
http://www.abc.net.au/news/2013-12-04/asio-arrests-key-witness-in-east-timor-spying-scandal/5132954
http://www.globalresearch.ca/canada-spied-on-brazils-government-as-part-of-global-commercial-espionage-campaign/5353642
http://www.smh.com.au/national/australian-spy-agency-helped-bhp-negotiate-trade-deals-20131106-2x1sw.html
https://www.techdirt.com/articles/20131111/11532125198/australia-spied-japan-to-help-companies-negotiate-trade-deals.shtml
http://www.crikey.com.au/2013/12/02/revealed-the-government-agency-stealing-ideas-from-businesses/
http://the-japan-news.com/news/article/0000940560
http://www.theguardian.com/uk/2013/jun/16/gchq-intercepted-communications-g20-summits
Even better, start not just having one TC volume, but many. Separate your stuff out by what you are doing, and unmount it when you are done. Word documents for client "A", open that specific volume, make an edit, unmount. Excel spreadsheets? Same thing.
This way, if the computer gets taken and the master drive image key slurped off, it means control of the OS, but not much else.
Even better, to prevent data leakage (/tmp files), the next step up is having virtual machines or Evalaze-sandboxed applications that channel all writes to one volume, that is easily unmounted.
TrueCrypt is just one tool in a toolbox.
Of course, there is the fact that people may not have to worry about seizure. My biggest security threat are the meth-heads who will break into a place just to grab stuff to take to a pawn shop or fence in order to stop their DTs. They don't care what's on the machine, so basic encryption turns a hardware + data theft into just hardware lost... which is easily replaced by insurance.
Yes, TrueCrypt implies windows.
The parent implied that his use of Linux and ecryptfs somehow protected him from this type of attack, which really it doesn't, just this particular implementation of this attack.
My point is, that other full disk encryption implementations are typically vulnerable to the same sort of attack, that is the encryption key is going to be stored in memory.
There are in fact tools to extract keys over firewire(or other methods) for a variety of operating systems, not just Windows and TrueCrypt, consider Inception
You mean like the Yubikey?
http://www.yubico.com/products/yubikey-hardware/yubikey/
Don't forget: you can still encrypt with a keyfile you keep on a microSD card in your wallet. [copy to a USB stick in a lockbox, in case you lose it or get robbed.] Then, they can have your key, they still need the file.
Pay no attention to the man behind the curtain with all your metadata.
Nice try, NSA.
Shut your machine OFF before you get to the border; don't put it to sleep.
The first question to ask is "Why you are carrying high risk/high value files across an international border?"
If you're using TrueCrypt but without full disk encryption, encrypt your pagefile: http://www.sevenforums.com/tutorials/143662-page-file-encryption-enable-disable.html
"Politicians and diapers must be changed often, and for the same reason."