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How to securely recycle or dispose of your SSD

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Re: How to securely recycle or dispose of your SSD

#41

Post by LogicX »

koliber wrote: post #40

Can someone explain to me how doing a low-level write of all zeroes to the disk is not effective, but rewriting the data in encrypted form is effective? Let's say I have a 100Gb SSD disc and it contains 25Gb of files. If I read in my unencrypted files, encrypt them and write them back to the SSD, they won't necessarily end up in the same physical place as the unencrypted files. Won't the unencrypted files still be th…

My naive understanding is that SSDs have portions of memory that go bad. They then use other, reserved portions of memory. As a result, not all of the memory is exposed for access to the host OS, only the on-drive controller sees the full picture. As a result, you may (at this time) believe youve taken a certsin action, but the reality is that the controller has likely not done what you expect. This is how you may think you've erased everything, but in reality, have not.

Re: How to securely recycle or dispose of your SSD

#42

Post by crottypeter »

koliber wrote: post #40

Can someone explain to me how doing a low-level write of all zeroes to the disk is not effective, but rewriting the data in encrypted form is effective? Let's say I have a 100Gb SSD disc and it contains 25Gb of files. If I read in my unencrypted files, encrypt them and write them back to the SSD, they won't necessarily end up in the same physical place as the unencrypted files. Won't the unencrypted files still be th…

I think the idea is that you never save anything to the disk unencrypted.

Zeroing out is not entirely secure because at the hardware level a newly zeroed bit might be distinguishable from a bit that was already zero.

Re: How to securely recycle or dispose of your SSD

#43

Post by jlgaddis »

rwmj wrote: post #39
marcosdumay wrote: post #28

Earlier quoted context omitted.

Yes, in any place where you are forced to disclose encryption keys.

dd if=/dev/urandom of=secret_terror_plan.doc In the UK that command could get you imprisoned indefinitely, especially if you're under suspicion for other reasons.

Hell, in the early 90s,

  C:\Windows> COPY README.TXT A:\VIRUS.EXE
(or something very similar), got me permanently kicked out of all computer classes in my high school so I can certainly believe that.

Probably even more so in the U.S.

Re: How to securely recycle or dispose of your SSD

#44

Post by MertsA »

comboy wrote: post #8
amelius wrote: post #5

> Lock It Up and Throw Away the (Encryption) Key That might get you into a lot of legal problems, [1]. [1] https://en.wikipedia.org/wiki/Key_disclosure_law

You mean filling your disk with some random bits? Is white noise already illegal?

Well arguably yes. Currently there have been a few cases where judges decided to hold a defendant in contempt of court indefinitely because they claimed to not remember their encryption keys. At least in one of the cases the burden of proof might as well just be if the judge has a hunch.

Here's one notable article from almost a year ago but last I checked he's still being held in contempt. https://www.techdirt.com/articles/20160428/07395434297/so-mu...

It's one thing to demand that someone turns over their password but currently AFAIK there's no rigorous proof that the data in question is even encrypted or that the defendant had decrypted it in the past beyond "it was on his computer".

Re: How to securely recycle or dispose of your SSD

#46

Post by falcolas »

devoply wrote: post #23
raverbashing wrote: post #17

Earlier quoted context omitted.

I agree Unless you're dealing with top-secret material, losing the encryption key is the best way Or just dd around 5x - 50x (or more if you're paranoid) its size to the disk - if you want to further reuse it. No, you won't have a meaningful amount of data remaining on the disk and extracting it requires special software/hardware. Unless you're dealing with data that makes the disk price irrelevant, you can follow th…

dd 1x-2x is enough in most use cases. most people don't have the time to go rummaging through random hard drive to recover what is mostly garbage. there might be a gem in there, but it's a straw in a haystack.

People have stranger hobbies. I can certainly see the appeal of buying used hard drives just to see what you can recover; part technical challenge, part voyeurism, and part schadenfreude.

Re: How to securely recycle or dispose of your SSD

#47

Post by coretx »

Ha! I've been trashing HDD's and USB sticks using old microwave ovens for decennia now. It's so simple. Remove the cover, place the ssd in the middle of the oven and blast your data. Ultra cheap, ultra secure. ( But do take personal security precautions )

Re: How to securely recycle or dispose of your SSD

#48

Post by masklinn »

rdl wrote: post #19
kalleboo wrote: post #12

They missed "blend it". Looks pretty effective. https://www.youtube.com/watch?v=1fXGVAadp5k

Blending (specifically in a dedicated blender jar, not one you ever use for food) is the best way to destroy SD cards I've found, and apparently a major fruit company has done this in the past. It's also a solid excuse to buy a blendtec 800 with sound enclosure for the office -- way quieter than any shredder. And good for making drinks.

> It's also a solid excuse to buy a blendtec 800 with sound enclosure for the office -- way quieter than any shredder. And good for making drinks.

Didn't you recommend against drinking electronics dust right at the start of the comment?

Re: How to securely recycle or dispose of your SSD

#49

Post by mbreese »

koliber wrote: post #40

Can someone explain to me how doing a low-level write of all zeroes to the disk is not effective, but rewriting the data in encrypted form is effective? Let's say I have a 100Gb SSD disc and it contains 25Gb of files. If I read in my unencrypted files, encrypt them and write them back to the SSD, they won't necessarily end up in the same physical place as the unencrypted files. Won't the unencrypted files still be th…

Building on what LogicX said... SSDs have a translation layer that converts the logical read/writes to the physical flash storage. So, low-level writes (from the OS's perspective) won't necessarily line up with what is physically written. I think that in theory if you wrote 5-10X the size of the drive, you might be able to write zeros to each of the flash pages, but I don't think you'd be able to confirm that.

Re: How to securely recycle or dispose of your SSD

#50

Post by michaelt »

falcolas wrote: post #46
devoply wrote: post #23

Earlier quoted context omitted.

dd 1x-2x is enough in most use cases. most people don't have the time to go rummaging through random hard drive to recover what is mostly garbage. there might be a gem in there, but it's a straw in a haystack.

People have stranger hobbies. I can certainly see the appeal of buying used hard drives just to see what you can recover; part technical challenge, part voyeurism, and part schadenfreude.

Back in ~2008 someone ran what they called "the great zero challenge" promising a prize to anyone who could recover data from a (60GB mechanical) hard drive after dd had overwritten the drive with zeros once.

The prize wasn't large, but the challenge got pretty good coverage on tech news sites, so it would have been good PR for any data recovery company.

Nobody accepted the challenge. I think recovering such data is impossible, and I'd be fascinated to be proven wrong - if you know anyone who could do so?

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