Data Destruction: Part One

[noid]

So, do we ban DT and send this thread to /dev/null for posting a repeditive topic?

As far as data decomissioning goes, I software wipe everything with DBAN. If I need to physically decom a drive I either shoot it, or put it on the drill press and make swiss cheese out of it.

[valkyrie]

Data Destruction

I am also thinking that even a metal brillo pad scratching the surfaces would do the trick. I wonder how fast the platters oxidize? At what point do they stop functioning?

This may assist in answering the question you posed about TTF from oxidation:

http://www.ukoln.ac.uk/services/elib...o-dig/dig6.pdf (page 58 most specifically addresses your question about length of time to rendering the data unreadable).

The answer seems to be "it depends." Previous operating conditions (temp, humidity) would probably impact the time it would take to render a drive platter unreadable. Because most platters are coated with ferrousmagnetic material, the surface indeed needs to be "scratched" to breach the coating and encourage pitting, which will further encourage oxidation. However, there does not seem to exist a standardized methodology to determine the length of time it takes for pitting and oxidation to be sufficient to render the drive platters disfunctional, and I expect it perhaps may be different for different types of drive media.

Though definitely low-tech, you may wish to try cracking a drive, and after having a go with a brillo, submersing the scratched platters in a brine solution, then drying them out; I would think the solution would have a more corrosive effect on the drive platters.

This could be an interesting research project. Though perhaps not nearly as much fun as using the drive for target practice. :-)

Sapere Aude

(edited for distinction in verbage between "drive" and "drive platters" and because I had nothing else to do at this time. :-)

[skroo]

Software destruction: DBAN is good, as is sdelete. Under teh loonix, I've used Wipe for a while. I really can't vouch for the effectiveness of any of these packages since I have no reasonable way to test them, so my statements are based on good faith in the developers' claims.

For physical destruction, one option other than shooting or slagging I've been anxious to try for a while is liquid nitrogen - the dip & drop technique. My guess is that it'd be more effective with some holes drilled into the drive case to allow more LN into the internals, but done right this could be a nicely permanent way of physically disposing of the entire disk.

Hm, there's an idea - put a couple of rounds through it to get the necessary ventilation as well as some basic destruction, then dunk it. Substitute live ammo for a drill press or similar as circumstances dictate and you could even do this in your bathtub.

[converge]

I've heard that while generally efficient.. the serious data destroyer has no option but physical, as methods of defeating software have been both theorized and developed.. depending on just how hardcore you are about retrieving the data.

Most popular physical means are usually thermite, slagging, or some similar form of physically deforming/warping/wasting the unit. For example, simply shooting, nailing, hammering the platter may take care of some but not all of the data... unless you're talking about the maniacs at the Defcon shoot.

A really inexpensive method of wasting the drive is buying a cheap/old/used microwave and let her loose. like the song by loverboy.. metal platters and GE just won't splice... or... will they??

I like CP99's idea though.. panel of judges for the Hard Drive Destruction Contest! judges on best method: most practical, cheapest, most thorough.

[CP99]

Having tried this, it's highly not recommended for the health of the microwave or the health of the humans nearby.

It also does'nt work very well.

A sealed hard drive will reflect the microwaves before they even hit the platters, damaging the magnetron and the oven in general.

......................

Hmmm, Hey DT, this is starting to sound like the pre-requisits for a contest...

Converge, I thought about using a microwave as well, but I havnt tested it, also I belive the Idea for the contest was rendermans as well. :)


CP

[TheCotMan]

Microwave radiation vs. metal will probably produce no or little damage to the metal.
Check out:
http://imagine.gsfc.nasa.gov/Images/.../emsurface.gif
as found on this web page.

From left to right, you have low energy, long wavelength, low frequency, until you move to the right ane encounter microwave, and then IR and THEN visible. It isn't until we get to the right of visible light (in that image) that we encounter UV and other, higher energy wavelengths capable of producing energy of ionization.

"microwave is to metal as a flashlight is to a mirror"
Microwaves would likely be reflected.

So, if microwaves have such little energy, and less heat-energy than IR, how can they warm our food?

A special property of the wavelength in the microwave portion of the spectrum is to cauese water molecules to vibrate quickly, and this vibration of water molecules bumping into other molecules is what helps to make the heat.

A search for "How do microwave ovens cook food" produced this on hit 2:
http://www.gallawa.com/microtech/howcook.html

Unless you have lots of water trapped in your platters, and you found some way for microwaves to not bounce off the metal and actually "vibrate" the water molesules that might be trapped, microwave ovens on hard disk platters should be the losers in a data destruction of HDD.

[converge]

/me removes tongue from cheek

[TheCotMan]

/me removes tongue from cheek

The first part pf your post was somewhat true though. There have been a few television stories and news-pieces on work at the CIA/NSA.One was recently part of a "morning show" where a guy interviewed a person who did disguises for the CIA, and another included an examination of how trash and old computer hard drives were "cleaned."

Physical destruction of trash and media was covered as a choice over software tools.

If I recall, their method for physical destruction was closer to shredding, chunking, grinding, and ultimately, bathing.

[CP99]

Well, "shredding, chunking, grinding, and ultimately, bathing" works well. But the way I see it, if its not overkill than, than why bother?

My 2 cents.
CP

Another thought:
What about using the drives as targets for a rail gun at the shootout? I’m sure a drive platter with some slugs stuck through it is pretty destroyed.

[robosycho]

Or if you can't get a hold of some thermite, you could use some potassium nitrate and sugar... And would it help at all to run 800 V through it? Because all you need for that is an artificial defilibrator. If you knew what the platters were made out of you could custom tailor a chemical packet to eat through them. Like splashing a little mercury on aluminum or a corrosive on glass. I doubt it would be possible to recover data from a platter that was covered in pockmarks and bubbles. For especially interesting results, unload the destructive agent while its spinning at full speed. And if you ever wanted to know what happens with metal and microwaves, stick a piece of aluminum foil in a microwave oven sometime. Keep a fire extinguisher handy.

[CP99]

Or if you can't get a hold of some thermite, you could use some potassium nitrate and sugar...

Potasium nitrate+sugar makes a homebrew smokebomb, not an all powerfull metal eater like thermite. Although fun to watch I doubt it would be effective at destroying a drive platter.

[klepto]

shred -n 65 -uvz *

replace * with whatever you want to remove, only works on non-journaling systems.

BSD does not have anything equivalent, although it does overwrite it 3-5 times? I don't remember.

[big chopper]

Magnets don't like heat. Could you bake them in an oven?
500 degrees for an hour?

[Dark Tangent]

Use BestWipe

BSD does not have anything equivalent, although it does overwrite it 3-5 times? I don't remember.

http://www.jetico.com/bcwipe_unix.htm for Linux, SunOS, Solaris, IRIX, Digital Unix, FreeBSD. You can create a boot ISO or run it stand alone.

[LosT]

I was thinking about this thread today at work...as I walked by the relfow oven...and the lead free solder pots full of liquid goodness....

And then started talking to one of our fab guys about how hard it would be to attach nasty tools to the pick and place machine....

Yeah, the solder pot would be fun...

LosT