Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

TrueCrypt Master Key Extraction And Volume Identification

volatility-labs.blogspot.com

Post reply on HN
Print view View original

61–70 of 75 posts

Re: TrueCrypt Master Key Extraction And Volume Identification

#61

Post by dobbsbob »

gambiting wrote: post #24
mrfusion wrote: post #19

Earlier quoted context omitted.

How would you treat your RAM contents as precious? Just making sure you're on a pristine machine, and nothing else is running? Can other unrelated processes access the key from RAM?

Well, in theory, let's say you've got a laptop encrypted with Truecrypt. You put it in sleep mode instead of switching it completely off or hibernating,because you are just nipping out for a coffee. An attacker could then steal it, lower its temperature(let's say they put it in a freezer for a while), and then extract - literally take out - the RAM from that machine and plug it into a specially prepared station which…

Cold boot attacks don't work on DDR3

Re: TrueCrypt Master Key Extraction And Volume Identification

#63

Post by nitrogen »

arbitrage wrote: post #35
alister wrote: post #30

A naive person googling about TrueCrypt and stumbling on this article (well written with an authoritative tone) will think that TrueCrypt is completely cracked, and not bother to use it. This research is interesting and useful, but do we really want to scare off people from using TrueCrypt? Couldn't you add a paragraph at the top or to the side that says, for example: "If TrueCrypt is used in the intended way, i.e.,…

We want more people to use it intelligently. If they're not capable of understanding the implications of this research, are they really going to be able to use this software effectively? How much hand holding do we need to do, here?

How much hand holding do we need to do, here?

I don't know who "we" would be in this case, but in general, I'd like to see enough hand holding that everybody can use encryption safely and confidently without having to be cpercival or tptacek.

Re: TrueCrypt Master Key Extraction And Volume Identification

#64

Post by sigterm »

dobbsbob wrote: post #61
gambiting wrote: post #24

Earlier quoted context omitted.

Well, in theory, let's say you've got a laptop encrypted with Truecrypt. You put it in sleep mode instead of switching it completely off or hibernating,because you are just nipping out for a coffee. An attacker could then steal it, lower its temperature(let's say they put it in a freezer for a while), and then extract - literally take out - the RAM from that machine and plug it into a specially prepared station which…

Cold boot attacks don't work on DDR3

Why? Do you have any reference?

Re: TrueCrypt Master Key Extraction And Volume Identification

#65

Post by kabouseng »

alister wrote: post #30

A naive person googling about TrueCrypt and stumbling on this article (well written with an authoritative tone) will think that TrueCrypt is completely cracked, and not bother to use it. This research is interesting and useful, but do we really want to scare off people from using TrueCrypt? Couldn't you add a paragraph at the top or to the side that says, for example: "If TrueCrypt is used in the intended way, i.e.,…

Your average Joe wont be reading this article... As soon as he sees the technical nature of the discussion, he'll move on.

Re: TrueCrypt Master Key Extraction And Volume Identification

#66

Post by unfamiliar »

crazytony wrote: post #59

I thought that this issue was already well known? Paging of virtual memory causes keys to be written to disk... But this article. Wow: "This is a risk that suspects have to live with, and one that law enforcement and government investigators can capitalize on" I love it. Only criminals use TC so let's call all TC users 'suspects'. What about people who have portable devices and want to store sensitive financial or me…

Its a forensic science post about how law enforcement can compromise TC. I'd be very worried if the people they were targeting weren't suspects.

Re: TrueCrypt Master Key Extraction And Volume Identification

#67

Post by kaoD »

jballanc wrote: post #39
6d0debc071 wrote: post #33

Earlier quoted context omitted.

Or, transmit random data on a schedule indistinguishable from the actual data, I suppose.

Hence numbers stations: http://en.wikipedia.org/wiki/Numbers_stations

Number stations are always so creepy. Now I'm scared to get out of my room.

Re: TrueCrypt Master Key Extraction And Volume Identification

#68

Post by dzhiurgis »

jessaustin wrote: post #29
kenj0418 wrote: post #25

Earlier quoted context omitted.

TrueCrypt offers a volume-within-a-volume option. The free space of a volume normally contains random data, and the hidden volume is presumably headerless. The idea is then to put something that you might want to hide in the outer volume (freaky porn, for example), then put your actual secrets (evidence of your criminal enterprise, for example) in the hidden volume. If forced to disclose the password, then only the o…

This isn't a panacea. Check out what the dm-crypt folks have to say about it (question 5.2): https://code.google.com/p/cryptsetup/wiki/FrequentlyAskedQue... tl;dr: even if your adversary can't "prove" you have another encrypted volume, when they can see all the random data on your disk or inside the "outer" volume, you can't prove you don't have an "inner" one. In a situation shitty enough that you're compelled to di…

Wait a minute.

If I zero out drive using traditional method - data is still recoverable.

If I zero out drive using random data - I can be suspect and/or get free rubber hose for life, trying to extract keys for something that doesn't even exist?

Re: TrueCrypt Master Key Extraction And Volume Identification

#69

Post by alexkus »

maxerickson wrote: post #18
deeringc wrote: post #13

Earlier quoted context omitted.

The flip side of this is that it becomes impossible for someone to prove that they haven't got an encrypted volume stored somewhere. It will be interesting to see in which way the courts go with this.

That's always been impossible.

Not always (as long as you're talking about something they are in possession of, you're right if you mean you can't prove that you don't have some flash drive hidden somewhere but, then again, it need not be encrypted if they don't have access to it).

To start simply, it's certainly possible to prove that a disk installed with a base install of an OS (and then never touched) contains no encrypted volumes if all of the remaining blocks are empty. Every file can be compared to a known good copy and if there's no other data anywhere on the disk then there can't be anything hidden on it.

From there it's a case of proving that each bit of extra data on this disk relates to a file available under the OS or a fragment of such a file (now deleted). This gets progressively harder the more the disk has been used.

It impossible to deny this when you have a GB+ sized area of unpartitioned data (or unmounted partition) containing seemingly random noise. Or a similar GB+ sized file that you cannot demonstrate to be something benign by unpacking/decrypting/etc. "It's a file of random noise I generated" is going to set off the alarm bells.

Re: TrueCrypt Master Key Extraction And Volume Identification

#70

Post by jessaustin »

dzhiurgis wrote: post #68
jessaustin wrote: post #29

Earlier quoted context omitted.

This isn't a panacea. Check out what the dm-crypt folks have to say about it (question 5.2): https://code.google.com/p/cryptsetup/wiki/FrequentlyAskedQue... tl;dr: even if your adversary can't "prove" you have another encrypted volume, when they can see all the random data on your disk or inside the "outer" volume, you can't prove you don't have an "inner" one. In a situation shitty enough that you're compelled to di…

Wait a minute. If I zero out drive using traditional method - data is still recoverable. If I zero out drive using random data - I can be suspect and/or get free rubber hose for life, trying to extract keys for something that doesn't even exist?

The authoritarians would like to be able to torture and imprison you based on nothing more than their whim, so that's why they set it up this way.

The authoritarians' apologists will probably note that to address your concerns, you should use random data first, to whatever extent you think will thwart recovery efforts, and then zero out your empty space.

Post reply on HN