Linked by Thom Holwerda on Sat 31st May 2014 00:12 UTC, submitted by teo
Privacy, Security, Encryption

Over the past 24 hours the website for TrueCrypt (a very widely used encryption solution) was updated with a rather unusually styled message stating that TrueCrypt is "considered harmful" and should not be used.

Very odd story. Lots of little red flags going up all over the place.

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Vulnerability
by Alfman on Sun 1st Jun 2014 05:09 UTC
Alfman
Member since:
2011-01-28

This is a very strange story, I hope we get some kind of press release with details, but who knows maybe the devs are intentionally going for mystique.

Interestingly enough Truecrypt is vulnerable, as is bitlocker and most likely all other encryption products to a pretty simple exploit:

http://www.prnewswire.com/news-releases/passware-kit-forensic-decry...

Passware Inc., a provider of password recovery, decryption, and evidence discovery software for computer forensics, announced that the latest version of its flagship product, Passware Kit Forensic, has become the first commercially available software to break TrueCrypt hard drive encryption without applying a time-consuming brute-force attack. It was also the first product to decrypt BitLocker drives.



Of course stealing the keys from memory may be considered "cheating" except for the fact that a very common interface, firewire, allows one to do just that by design...

http://www.pcworld.com/article/143236/article.html
Researcher Adam Boileau, a consultant with Immunity, originally demonstrated the access tool at a security conference in 2006, but decided not to release the code any further at the time. Two years later, however, nothing has been done toward fixing the problem, so he decided to go public.

"Yes, this means you can completely own any box whose Firewire port you can plug into in seconds," said Boileau in a recent blog entry.
...
The attack takes advantage of the fact that Firewire can directly read and write to a system's memory, adding extra speed to data transfer. According to Boileau, because this capability is built into Firewire, Microsoft doesn't consider the problem a standard bug.



http://www.hermann-uwe.de/blog/physical-memory-attacks-via-firewire...

All of this is done by exploiting a "feature" of the Firewire spec (OHCI-1394) (PDF), namely that it allows read/write access to physical memory (via DMA) for external Firewire devices. Worse, as this is DMA, the CPU/OS will not even know what's going on. Even worse, this works regardless of whether you have locked your screen with a password-protected screensaver, or xlock, or vlock, or whatever. As long as the system is running, you're vulnerable.


I don't know if the information is still current. If I recall it still applied to firewire hardware sold in 2010, which was incapable of controlling access to ram from attackers. This is not a shortcoming of truecrypt, but it should never the less be of particular interest to it's users. Hardware that leaves a backdoor wide open to just about every security mechanism ever devised, what a lame design!

Edited 2014-06-01 05:12 UTC

Reply Score: 3

RE: Vulnerability
by Soulbender on Wed 4th Jun 2014 07:19 in reply to "Vulnerability"
Soulbender Member since:
2005-08-18

I tend to believe press-releases by security companies as much as a believe in Santa Clause and the Toothfairy.

Long believed unbreakable


And it still is. Stealing the key by abusing DMA and using custom hardware is pretty clever but they still haven't broken truecrypt.

Reply Parent Score: 2

RE[2]: Vulnerability
by Alfman on Thu 5th Jun 2014 15:02 in reply to "RE: Vulnerability"
Alfman Member since:
2011-01-28

Soulbender,

I tend to believe press-releases by security companies as much as a believe in Santa Clause and the Toothfairy.


Sure, but the point of my link was intended to be educational since many end-users probably don't realize they are vulnerable to such a trivial & highly effective attack.

And it still is. Stealing the key by abusing DMA and using custom hardware is pretty clever but they still haven't broken truecrypt.


They haven't broken truecrypt's encryption itself, but arguably they have broken one of it's use cases. You don't even need custom hardware, just an ipod will do. It's not adequate to simply lock the computer or shut the lid when you leave (ie for a short bathroom break).
http://www.wilderssecurity.com/threads/truecrypt-standby.246757/

Edit: I've not used it, but apparently "Rohos Disk" is designed to protect against the "wake up from sleep" attack:
http://www.rohos.com/2011/11/timeout-feature-for-rohos-disk-encrypt...


Even taking security out of the equation, it's poor to give external devices free reign over host ram from a robustness point of view too. The solution to this is so obvious I don't know why it wasn't engineered into the firewire spec from version 1: only allow external devices to perform DMA against memory buffers allocated by the host. Ie a video camera should only have access to it's own video buffers and nothing else.

Edit: For the sake of completeness, I should mention that memory is vulnerable to another process by which running DRAM can be chilled and physically transferred to another device to copy it's contents, however this is less reliable due to the sensitive nature of the operation and the existence of CPU caches, etc. Not to mention such an attack would much more obvious from a physical perspective.

Edited 2014-06-05 15:20 UTC

Reply Parent Score: 2

RE: Vulnerability
by zima on Wed 4th Jun 2014 18:03 in reply to "Vulnerability"
zima Member since:
2005-07-06

Luckily Firewire seems to be going away?...

Reply Parent Score: 2