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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

#51

Post by londons_explore »

LogicX wrote: post #41
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 th…

The controller stops you accessing some parts of the drive, but it also stops the attacker from reading those same parts.

Only a very advanced attacker is likley to be able to read those reserved sectors and be able to reconstruct data from them.

I'd say you are safe from everyone except the drive manufacturer, state actors, and people with more than $50k to gain from extracting info.

Re: How to securely recycle or dispose of your SSD

#52

Post by semi-extrinsic »

sborra wrote: post #29

What about the chemical option - attacking the board with a strong acid. Are there any readily available acids that would do the trick?

There are several more-or-even-more nasty chemicals that will damage PCBs to various extents. But none of those methods should be undertaken without using either a supplied air full-face mask or a proper fume hood, and all of them leave you with the problem of safely disposing of nasty chemicals at the end. Mechanical destruction is cheaper and safer.

Re: How to securely recycle or dispose of your SSD

#53

Post by londons_explore »

coretx wrote: post #47

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 )

hdds act as a big metal faraday cage, and the actual magnetic media will probably survive.

USB sticks the actual flash memory chips have input protection diodes and are quite physically small (limiting the voltage across them), so again I wouldn't be surprised if they survived.

Re: How to securely recycle or dispose of your SSD

#55

Post by michaelt »

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…

The encryption relies on you using (and trusting) the drive's built in encryption function.

Most SSDs with built in encryption don't directly encrypt the data with your password - they encrypt the data with a random password, then encrypt that random password with your password. They do this so you can change your password without having to re-encrypt all the data on the disk (which would be slow, and could cause data loss if there was a failure during the re-encrypt process).

Even when you haven't set a password set on your drive, most SSDs encrypt all the data on the actual flash chips (including reserved space, unused space and spare/reallocated sectors) and just store the random password is unencrypted on the same drive. By activating the on-drive encryption, the random password gets encrypted - making your data unrecoverable.

Of course, on-drive SSD encryption is all unauditable closed source stuff. And the cops have complained much more about iPhone encryption than SSD encryption. Make of that what you will.

Re: How to securely recycle or dispose of your SSD

#56

Post by muse900 »

Sorry but I find that this blog has an error.

It says encrypting it and throwing the key away is going to make data unrecoverable.

While thats true for now, what happens when tech reaches the point that current encrypted items can be done within milliseconds?

So yes while encrypting it will make it so that the person that wants to extract information out of it can't do it with the current tech, but whenever a breakthrough on that field will happen then that person will be able to decrypt the SSD.

Re: How to securely recycle or dispose of your SSD

#57

Post by elif »

$1000 to shred an SSD?

i bet 20 rounds of 12 gauge for $15 would sufficiently pulverize it. Maybe this wasn't written by an american?

What about some kind of acid bath to liquefy the silicon?

Or even our old free plasma generator: bonfires?

I think there are fun/creative/cheap routes not explored in this article.

Re: How to securely recycle or dispose of your SSD

#58

Post by justinclift »

> Without having the passphrase or encryption key to recover from, any data on that drive is useless to anyone that finds it.

Isn't it widely suspected the TLA's have backdoors to the encryption used SSD makers? eg depending on who you're wanting to keep things private from, using any built in SSD encryption might not be the right approach.

Re: How to securely recycle or dispose of your SSD

#59

Post by gens »

michaelt wrote: post #50
falcolas wrote: post #46

Earlier quoted context omitted.

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…

Apparently the NSA would. (somewhere around the shredding part; don't have time to find exact)

https://www.youtube.com/watch?v=-bpX8YvNg6Y&feature=youtu.be

Re: How to securely recycle or dispose of your SSD

#60

Post by DanBC »

djaychela wrote: post #9

I'm constantly amazed at the waste that happens when people decide they are going to destroy an old (serviceable) hard drive because they want to protect their old data on it. I don't see a need in 99% of cases, when there are perfectly good ways to permanently delete the data and make it unrecoverable, albeit taking a longer time. No doubt I'll get shot to bits for this with various edge cases where it's important t…

Disc drives are consumable items. They only last 5 years. They're so fragile we treat them as if they're going to fail at any time - we have multiple backups in many places.

We shouldn't be encouraging people to use them for as long as possible, we should be encouraging better recycling.

I agree about other electronics though - the constant upgrade cycle is very damaging to the environment.

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