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"Smash Your Hard Drive" To Fight Identity Theft

Posted by CmdrTaco on from the i-can-get-behind-that dept.

Will Do This For Free writes "BBC News has a story about the only fireproof way of safeguarding your personal information when dumping your old computer: 'It sounds extreme, but the only way to be 100% safe is to smash your hard drive into smithereens. [...] The more thoroughly the better.' This sounds like so much fun that I almost feel like doing it right now. Let me press Submit Story first."

24 of 527 comments (clear)

  1. I find a Magnet Works by s31523 · · Score: 3, Informative

    I have a heavy duty magnet that when placed on the top of the drive makes the drive completely useless.
    I doubt anyone could recover data from it, as it is surely scrambled.

    1. Re:I find a Magnet Works by dword · · Score: 2, Informative

      If you work for a big company, chances are you are very interested in this article and it doesn't sound retarded at all. I was actually asked by one of my ex-employers for the best method to dispose of a hard-disk so that nobody could retrieve information from it, for good reasons.

    2. Re:I find a Magnet Works by Yvanhoe · · Score: 2, Informative

      Actually, I think that an unmodified hardware with a modified hardrive driver is able to retrieve data that was zeroed once with a good accuracy. The trick is to get the analogic value measured by the magnetic head instead of just 1 or 0. If you measure all zeroes as 0.001 and 0.100 values and ones as 0.9 and 0.999 values, it is not hard to guess what the previous value of each bit was.

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    3. Re:I find a Magnet Works by DavidTC · · Score: 2, Informative

      The 'previous value' of each bit is nonsense.

      For one thing, hard drives do not store data like that. They store a one when the data changes, and a zero when it's the same. So 11010011 would actually be written as written as 10111010.

      A quick thought will demonstrate that not knowing the value of any bit will render the entire rest of the byte unknown.

      More importantly, bytes start without a value. They are in indeterminate state, they are magnetized. They are essentially .5. They are then formatted, at the factory, by writing a 'zero' to them.

      Pretending that your idea worked (Which it doesn't.) every bit would read as a one. (Or, rather, every bit as a change bit, resulting in the data being 10101010.)

      However, your idea is dumb to start with, because, as the other reply points out, hard drives aren't storing 0 or 1. They're storing 0.0-0.3 and 0.7-1.0, because hard drive manufactures make them as dense as possible, to the point that when writing one bit, you can't help but slightly alter the bit ahead or behind it. The development of hard drives is a contest to produce less overlap when writing.

      Which means if you were to actually read the value of a bit, there would be a good chance it was 0.2 not because it 'used' to be a 1, which incidentally doesn't work that way, but because it has a 1 after it.

      This is actually somewhat of a simplification, because in actuality, at the base level, hard drives are 'analog'. The strength of write is not a square wave, or even a jigsaw wave. It is much smoother than that. It is like transmitting morse code using a slide whistle.

      I know there are lots of stupid urban myths about how hard drives work, but if there was a way to recover data from an overwritten hard drive, it would immediately get used to store more data on the drive.

      The only way to recover data from a zero'd hard drive is to look for remapped sectors.

      --
      If corporations are people, aren't stockholders guilty of slavery?
  2. Or make it reusable... by Seakip18 · · Score: 5, Informative

    and just use dBan, Derrick's Boot and Nuke.

    Nothing beats an afternoon of watching dBan and a comfy chair. Beer or whisky optional.

    --
    import system.cool.Sig;
  3. Environmentally criminal! by thegoldenear · · Score: 3, Informative

    This recommendation from Which? magazine has incensed me today. They're reported as saying "It sounds extreme, but the only way to be 100% safe is to smash your hard drive into smithereens.". There's no need to do this if you use disk wiping software, which is probably even better than a hammer; as the BBC article points out. Darik's Boot And Nuke is perfect for this. It's environmentally criminal to be suggesting the best way to wipe a disk is to smash it.

    Pete Boyd

    1. Re:Environmentally criminal! by Lumpy · · Score: 4, Informative

      Problem is that most people are way too stupid to understand how to use that, but they can understand smash.

      The funny part, 90% of those people that understand smash, will not smash it enough. I have recovered data from laptop hard drives that looked pretty smashed, but 45 minutes in my improvised clean room moving the platters to a different drive and I was able to read the contents.

      --
      Do not look at laser with remaining good eye.
    2. Re:Environmentally criminal! by Lumpy · · Score: 5, Informative

      It's really not that hard to transfer platters. and yes use an identical drive.

      a makeshift clean room is easy. run the shower in the bathroom for 15 minutes on the hottest setting and then shut it off and let the room cool down completely. the mist in the air will remove all dust as it falls to the ground. use a tyvek suit and cover your hair, face, hands and you're good to go.

      --
      Do not look at laser with remaining good eye.
  4. Some ideas for destruction by necro81 · · Score: 3, Informative

    Revision3's Systm show had an episode that suggested some ways for destroying a hard drive yourself. They took the position that using a program like Boot'nNuke, which overwrites data 1-N times at your choosing, is sufficient to sanitize data without destroying the drive.

    If you want to go the nuclear option, they demonstrated some favorites: mangling the platters in a vice, dremel or hand grinder, propane or cutting torch, melting it in thermite, etc.

    A hospital I worked for once, when decommissioning old computers, would take the hard drive over to a drill press and put a couple holes through it. Nowadays I think they've bought a drive shredder.

  5. Re:"The only fireproof way of safeguarding your da by Anonymous Coward · · Score: 5, Informative

    The platters don't have to be melted, they only need to be heated to the Curie point to loose all their information. Of course, that would still take a pretty hot fire.

  6. Just wipe it once by GFree678 · · Score: 4, Informative

    Really, there's no need to wipe it more than once unless you honestly think it will matter. At least these guys think so:

    http://16systems.com/zero

  7. Re:In other news by hairyfeet · · Score: 4, Informative

    In other news: people still stupid. Has anyone here actually TRIED to get stuff back off a Guttmann wiped drive? Or even a DoD 7 wiped drive?

    My class in computer security had some time to kill and someone brought that up so the teacher said "Well, we've got a bunch of PCs from last upgrade waiting to be re-imaged and given away to students...let me see what I can score us!". He ended up getting us a half a dozen PCs set up in the back of the class with 2 HDDs set up in each so we could run plenty of different tests. We did everything from MSFT format to one pass to three pass to DoD 7 to Guttman. We researched and then used every piece of freeware and trialware that we could get our little hands on. Here is our findings:

    MSFT format is of course pointless, as everyone knows. 1 pass of zeroes we got around,sorry but it has been awhile, but we got around 80% IIRC. 3 pass was lower(0,1,random), somewhere in the 10-20% range, depending on the software used, but most of the "recovered" data was garbled beyond use, DoD-7 made it pretty much impossible, I think we got 2 .txt files and they were so garbled we couldn't decide if it had actually recovered ANYTHING, certainly nothing you could use, and finally Guttmann we got squat.

    So if someone were to spend the $$$$ to have the drive taken apart in a clean room and analyzed and you only used one or two pass of predictable patterns then yeah, I might see wanting to destroy. But I haven't seen anyone bragging about beating D0D-7 with what the average hacker would have access to, much less Guttmann. So frankly unless someone here has a citation I have to call bullshit. Frankly it makes me wonder if this kind of stuff isn't cooked up by the HDD manufacturers. I can just imagine them spinning this- "Before giving away that machine destroy the hard drive first!(so they'll have to buy a new one from us! Yay!)"

    --
    ACs don't waste your time replying, your posts are never seen by me.
  8. DOD Guidlines. Re:"The only fireproof by Forge · · Score: 5, Informative

    I read years ago (and I'm sure it was made up) of a memo sent out to IT managers in the DOD (United States Department Of Defense). It went.
    To properly dispose of hard drives which may contain Top secret information is a 5 step process to be performed in the order specified and by competent engineers.

    1. Perform a triple overwrite security erase on the entire disk.
    2. Use a bulk degausser (AKA a powerful electro magnet).
    3. Crush the drive under a roller or tank tracks, whichever is more convenient.
    4. Melt the scrap into slag.
    5. Bury that Slag in a toxic waste dump to deter any attempts at data recovery.

    That's not exactly how it went but I think this is pretty close. Can anyone find the original?

    --
    --= Isn't it surprising how badly I spell ?
    1. Re:DOD Guidlines. Re:"The only fireproof by penguinboy · · Score: 4, Informative

      There's no original because that's not the spec.

      The real spec is DoD 5220.22-M, available at http://www.dtic.mil/whs/directives/corres/html/522022m.htm.

    2. Re:DOD Guidlines. Re:"The only fireproof by Kilroy · · Score: 2, Informative

      This is incorrect and has been for a long time.

      See: http://www.usenix.org/publications/library/proceedings/sec96/full_papers/gutmann/index.html

  9. Re:In other news by SatanicPuppy · · Score: 4, Informative

    Hard drives are cheap. If you have any data that you absolutely don't want to get out...EVER...physical destruction is the 100% solution.

    And, in terms of practicality, running DoD-7 takes about 1000 times longer than whipping out the old Sledge-O-Matic. If you're retiring a few dozen computers, even that gets old, and you start looking for the thermite.

    --
    ad logicam Claiming a proposition is false because it was presented as the conclusion of a fallacious argument.
  10. Re:In other news by D3 · · Score: 3, Informative

    You are spot on and I would mod you up if I had points. I don't think the HDD manufacturers are behind this though. The simpler (and I think correct) reason is that older media used to be easier to recover data from. Newer hardware is different and the old methods do not apply. http://shsc.info/DataRecovery#titelanker5

    --
    Do really dense people warp space more than others?
  11. Re:"The only fireproof way of safeguarding your da by Retric · · Score: 2, Informative

    Heating a destroys the magnetic domain's long before it melts. As density increases the ability to do data recovery when things go bad keeps decreasing.

  12. Re:"The only fireproof way of safeguarding your da by somersault · · Score: 3, Informative

    Whoosh!

    The point was that they said this is a "fireproof" way of restoring your data - which is basically saying that throwing the hard drive into a fire would somehow recover the data.

    Foolproof would have been a better word to use; as in "even a fool could protect their data using this method".

    --
    which is totally what she said
  13. Re:No you don't. by couchslug · · Score: 2, Informative

    Don't forget to harvest the handy magnets if you bother to do it that way.

    Some hard disk platters are glass, so be careful!

    --
    "This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
  14. Shoot It by maz2331 · · Score: 2, Informative

    Five shots from a .458 Winchester Magnum firing soft-points really wrecks a drive into smithereens. It's actually hard to find a spot on the platters that isn't either punched through or scratched to near-oblivion by tiny fragments bouncing around inside the thing. Really, they look almost sandblasted where not outright gone.

    And it is a lot of fun, too.

  15. DoD standard superceded by NIST's standard by Anonymous Coward · · Score: 3, Informative

    There's no original because that's not the spec.

    The real spec is DoD 5220.22-M, available at http://www.dtic.mil/whs/directives/corres/html/522022m.htm.

    The DoD standard has been superceded by NIST Special Publication 800-88:

    http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-88_rev1.pdf
    http://en.wikipedia.org/wiki/Data_remanence

  16. Re:In other news by gknoy · · Score: 2, Informative

    Well if you can't access it in any way, then why would it matter?

    The drive's firmware is what keeps track of where the "good" and "bad" sectors are on the drive. Presumably, if you took the platters out, and put them in a different drive, it would have no idea which were the good or bad sectors, and therefore WOULD let you read those sectors. No guarantees that what it reads was what was originally there, but I'd be surprised if it didn't let you read them.

  17. Re:Not cheap if computer is free by Gilmoure · · Score: 2, Informative

    Yup, my work donates newer stuff to local school board but all they get is case/logic board/processor/powersupply. They pull ram/drives/video cards. Can also pick up older stuff at auction but it's sold by the pallet, usually for under $100.00. Got a load of old Mac stuff this way but had two nice G5's in there.

    --
    I drank what? -- Socrates