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Security Encryption Operating Systems Software Windows

Bitlocker No Real Threat To Decryption? 319

An anonymous reader writes "The Register is running a story called 'Vista encryption 'no threat' to computer forensics'. The article explains that despite some initial concerns that lawbreakers would benefit from built-in strong encryption, it's unlikely the Bitlocker technology will slow down most digital forensic analysts. What kind of measures does one need to take to make sure no one but yourself has access to your data? Is Bitlocker just good enough (keeping out your siblings) or does it miss the whole purpose of the encryption entirely?" One would hope an international criminal mastermind could do better than the encryption built into Vista.
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Bitlocker No Real Threat To Decryption?

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  • Re:PGP? (Score:2, Interesting)

    by INeedAttention.com ( 958052 ) on Monday February 05, 2007 @09:55PM (#17899142) Homepage Journal
    It wasn't legislation it was an appellate court decision. Source: http://news.com.com/Minnesota+court+takes+dim+view +of+encryption/2100-1030_3-5718978.html [com.com]
  • Re:Well for one (Score:2, Interesting)

    by HomelessInLaJolla ( 1026842 ) * <sab93badger@yahoo.com> on Monday February 05, 2007 @10:00PM (#17899192) Homepage Journal
    > so anything said against Vista will be modded "Insightful" without the barest show of proof?

    It's a logical conclusion--not only is it "a" logical conclusion but it is the most probable conclusion. The people with the strongest backgrounds in computer security, working for Microsoft, will be associated with other people with the strongest backgrounds in computer security. Those with the strongest backgrounds in computer security are most likely to be associated with governmental agencies, and in possession of the necessary security clearances, which allow them to work there.

    Thus, those who know the most deeply buried exploits for Windows Vista (especially the exploits which may even be specific to particular hardware) are in the social circles which are closest to organizations such as the NSA.

    It's all very statistical and it makes perfect sense. The only possible defeat would be if Vista had no security exploits and we don't need to cite any links to know that is false.
  • Summary of article (Score:4, Interesting)

    by Anonymous Coward on Monday February 05, 2007 @10:01PM (#17899202)
    Just to save everyone the time....

    "If you don't use encryption technologies properly, they will not serve it's purpose."
  • by daeg ( 828071 ) on Monday February 05, 2007 @10:50PM (#17899598)
    Depends. If you're faced with something like a TrueCrypt volume, even knowing a single file will get you pretty much nowhere. The entire volume is full of random bits, in fact, written data looks just like random data. So even if you knew there was a file.txt with contents "HELLO WORLD", you have a lot of data space to comb through. Throw into that mix that the entire file system is encrypted -- hell, you may not even know what file system you're looking for.
  • Re:I use TrueCrypt (Score:2, Interesting)

    by ohsoot ( 699507 ) on Monday February 05, 2007 @11:00PM (#17899672)
    Be careful when using truecrypt on a USB flash drive.

    http://www.truecrypt.org/docs/wear-leveling.php [truecrypt.org]

    The above link is the official explanation, but the jist of it is on a USB drive with wear leveling the drive will evenly spread data over the entire drive to extend the life of the drive. This means that truecrypt can not ensure that the old header is overwritten if you do something like change the password on the drive.

    My understanding is that if you encrypt the entire USB drive and never change the password you should be OK.
  • > beyond years and years of bruteforce processing

    Or a really big botnet [google.com].

    Duh.
  • by KWTm ( 808824 ) on Monday February 05, 2007 @11:28PM (#17899880) Journal
    One major advantage of TrueCrypt: works on both Linux and Windows. Can't remember if there's a Mac version. Nope, there isn't. Here's the TrueCrypt web site [truecrypt.org].

    Having researched TrueCrypt and compared the alternatives, I have started using it routinely. It's not so much that I have something to hide, or that what I want kept private requires as strong an encryption as TrueCrypt. It's more than I simply want a convenient way to encrypt something, forget about it, and not have to worry about it later.

    My personal financial data resides in a TrueCrypt volume. To lock up all of those files, I just umount the volume, and that's it.

    I also wanted to make an offsite backup of our more valuable personal data in case of disaster, such as a fire that burns down our home, destroying the backups stored at home. For example, we have some digital photos with some irreplaceable priceless memories. So I decided to burn them onto DVD and have my relatives, who live out of town, hang onto copies. But relatives can be nosy, and interspersed in the photos could be things I don't want other people to see, from badly taken photos that "make me look fat" to photos of bank statements and legal documents for which we wanted to store a non-paper copy.

    So, I created TrueCrypt volumes of the appropriate size to burn to DVD, and then stashed our photos inside. We've got about 4 years' worth of photos (JPEGs) on two (different) DVDs with our relatives in two locations.

    I don't want to encrypt something with cheap encryption, and then worry 4 years down the road when someone discovers a flaw in the scheme. You might ask, "What? Are your non-geek relatives going to go about cracking your encryption?" You never know. What if I become someone --let's not say famous, but prominent? Say some sort of social activist fighting for software freedom? Who knows what could happen to my offsite backup DVDs in 4 years --suppose some hired maid accidentally dumps them in the trash, and are noticed by the neighbourhood trash-diving geek? What if some big company or other enemy happens to get their hands on copies and try to use some embarrassing photos to pressure me? I want to be able to rip off my tinfoil hat and laugh, "Don't be ridiculous! That would never happen!"

    TrueCrypt gives me that peace of mind. Among its other features is multiple scheme encryption. Are you worried that AES might get cracked next year? Encrypt with AES, and then encrypt the result with Blowfish.[1] Or Twofish first, then CAST5. TrueCrypt offers multiple options, and it does not store the result anywhere. How does it know that you used AES-then-Blowfish encryption? Because it tries all of the schemes one by one. It tries AES alone with the password you gave. Doesn't work. Tries Blowfish alone. Tries about half a dozen other single-encryption schemes. Then it tries the multiple combinations: Blowfish-Serpent, then AES-Blowfish, etc., going down the list until something works. If nothing works, then it concludes that you entered the wrong password.

    It's not a perfect solution, and one drawback with TrueCrypt is that I can't use it on my work computer where I don't have administrator rights. But otherwise it has all the advantages I'm looking for: secure, cross-platform, on-the-fly, open source freedom ... and most of all, it's usable: it exists and is easy to use. Because, much as crypto-security fascinates me, I don't want to tinker all the time.

    Just like a screwdriver: when I want to use it, I don't want to have to Google for user manuals. I just want to do what I need with it, and not have to think about it.

    ---
    [1]: Incidentally, the advantage of AES-with-Blowfish is *not* that you can't crack Blowfish even after the AES on your TrueCrypt file is cracked. Once your AES crypto is cracked, the password is known and the same password will be used for the Blowfish decryption. (Remember, TrueCrypt is open source --once the
  • by Matey-O ( 518004 ) <michaeljohnmiller@mSPAMsSPAMnSPAM.com> on Monday February 05, 2007 @11:55PM (#17900072) Homepage Journal
    Having just completed a Forensics bootcamp, I was frankly amazed at what the current state of the art practices are in password cracking. Even the smallest commonly used keys would take a Computer for Every Person On the Planet 300,000 years to brute force crack.

    Face it, you ain't gonna get there with more horsepower.

    But, the guy's a Bronco fan? Index broncos.com and add it to the dictionary. Enter his wife, daughter, marriage date, favorite car, and pets. The dictionary generation software has taken great strides in Making lists of MuffySpot1996 type entries.

    Not enough to crack your password? Hmm. Better hope you didn't use it with another program that happened to write it's ram to swap. The forensics tools index EVERY number and word on the drives you enter into evidence. Evidence can be data from your iPod, cellphone, and PDA. It can be from the exchange server and it can be from hotmail.com

    Is he Russian? Add the russian dictionary to the search.

    So, here's what we have: a Custom dictionary, Russian and English dictionaries, an index of every unique character string captured on all removable and non-removable storage.

    That's a lotta chinks in the armor. And Crooks usually aren't that smart.

    It was a very enlightening class. During the lab it _easily_ guessed my tier two and three passwords...it didn't get my tier one Passwords, but I didn't enter all my evidence for submission either.

  • Re:I use TrueCrypt (Score:2, Interesting)

    by Anonymous Coward on Monday February 05, 2007 @11:58PM (#17900100)
    Yes, TrueCrypt would stand up to a disassembly of the drive. You're missing the point. What the TrueCrypt people mean by "plausible deniability" is this. You can create a hidden volume within another TrueCrypt volume. It's pretty obvious the first volume is encrypted (unless you can convince someone that you have several hundred MB of random data lying around in a file "just because"). However, free space on an encrypted volume looks statistically random. TrueCrypt can create a second volume in this free space, which is called the "hidden volume". If you don't know the second password, not only can you not access the hidden volume, it is impossible to prove it exists. Encrypted data and encrypted free space both look perfectly random unless you know the second key.

    Now, as for "plausible deniability", consider this scenario: You have an encrypted volume on a USB key with a hidden volume within it. If you give TrueCrypt password1, it shows you the encrypted volume. If you give it password2 instead, it shows you the hidden volume. If someone takes your USB key and threatens to torture (arrest, whatever) you unless you give them the password, you give them password1. There is no way for them to tell whether or not another volume exists. You can deny that a hidden volume exists and there is no way for anyone to prove you wrong.

    If you still don't get it, check the explanation at the TrueCrypt website here [truecrypt.org] and here [truecrypt.org].
  • Re:Well for one (Score:3, Interesting)

    by swillden ( 191260 ) * <shawn-ds@willden.org> on Tuesday February 06, 2007 @01:58AM (#17900834) Journal

    And no one will ever, ever, ever steal that key.

    If you're willing to throw a little money at it, that's fairly easy to ensure, actually.

    First, you use a hardware security module to generate the key pair, configured to refuse to ever give up the private key. Ever. With a good HSM, even if the attacker has complete control of the device odds are slim that he can extract the key.

    Second, you put this hardware security module in a secure facility, with appropriate processes in place to ensure that the HSM never leaves the building, under any circumstances, regardless of who wants it to, and that only authorized people with appropriate need have access to the HSM to use it to decrypt disks.

    And technology will never progress to the point where that key becomes crackable.

    Barring (1) a significant mathematical breakthough and (2) a huge improvement in the practicality of large quantum computers, that won't happen. It's easy enough to use a sufficiently large key that Moore's law would have to continue unabated for millions of years to make a brute force search feasible.

    And the guarding of the "secure" back door will always be much much better than I could possibly guard the "front door," so it's no problem for my security.

    Assuming it's not the NSA that wants your data. OTOH, if the NSA wants your data badly enough, they're almost certainly going to get it. Unless you're dead.

    The biggest problem with this sort of backdoor, IMO, is that it's too easy for the user to defeat. All the user has to do is to overwrite the copy of the disk encryption key that is encrypted with the NSA key with some random data. The system could be designed to make that difficult, of course, but it will never be impossible, not on a general-purpose computer.

  • by Schraegstrichpunkt ( 931443 ) on Tuesday February 06, 2007 @02:16AM (#17900930) Homepage

    In some ways, the issue boils down to who is more knowledgeable about the use of encryption or other security technologies: investigators or the targets of investigation,

    In other words, Microsoft really hasn't learned much about security over the last 10 years. They still design security systems that are prone to operating in insecurely. This looks like the "Do you want to run this ActiveX control?" dialog all over again.

  • Re:PGP? (Score:5, Interesting)

    by init100 ( 915886 ) on Tuesday February 06, 2007 @03:15AM (#17901238)

    But it is true that if you are on trial for a crime in Minnesota, there's a precedent for the mere fact that you have PGP software on your computer to be used against you as evidence for the prosecution--despite the prosecutor's witness himself saying that PGP capable software is already available in OSX.

    So, if you're on trial in Minnesota, you'd better not be using a Mac? Or Linux, since many distributions also include GnuPG.

    Conclusion: Use Windows to be safe. It's encryption software is bad enough to not make you go to jail.

  • by Kjella ( 173770 ) on Tuesday February 06, 2007 @07:21AM (#17902542) Homepage
    Most people pick a crappy passphrase, when in reality it's not that hard choosing a good passphrase. Start off with a passphrase, plain english and something you'll remember by heart:

    "oneringtoholdthemallandindarknessbindthem"

    Throw in the following three things:
    1) Capital letter
    2) Number
    3) Special char

    "onerinGgtoholdthemallandindark666nessbin!dthem"

    Now remember the "special words": rinGg, dark666ness, bin!d, you'll find those much easier to remember in context.

    The length kills any brute force attack, with the added "typos" the number of permutations is huge, killing any dictionary attack. In fact, this one is probably way overkill already.
  • by arevos ( 659374 ) on Tuesday February 06, 2007 @08:18AM (#17902814) Homepage

    The presence of Truecrypt on the base system will reveal the possibility that this is done. Any competent investigator will look. Especially when the partition sizes in use don't add up to the total size of the drive.

    If a user has a 1GB Truecrypt volume, but has only used up 100M, this could be indicative of a hidden volume, or it could be that the user hasn't used up all the available free space on the volume. Even if the investigator suspected there was a hidden space, he'd need some evidence that the suspect had an additional encryption key over the one supplied.

    Now, this could be found through surveillance of the suspect beforehand (keyloggers, hidden cameras, etc.), but that applies to encrypted USB sticks as well. In addition, there's a chance that your USB stick might be discovered, whilst there's no danger of the same thing happening to a Truecrypt volume. So far as I can see, an encrypted USB stick is considerably less secure than a hidden Truecrypt volume.

    Of course, for extra security, why not a hidden Truecrypt volume on an encrypted USB stick?

  • by Sunthalazar ( 69878 ) on Tuesday February 06, 2007 @01:16PM (#17906650)
    This is almost definitely a 'random' code generated by a human. Simply because it has no 5 and a disproportionate number of 7s. (it also has no 0, which again hints at a human origin).
    0 - 0
    1 - 4
    2 - 4
    3 - 8
    4 - 5
    5 - 0
    6 - 6
    7 - 15
    8 - 5
    9 - 2

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