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How secure is merely discarding (TRIMing) all of a SSD's blocks?

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Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#31
post #24
post #11

Earlier quoted context omitted.

Shredding/sledgehammer is likely the best option for secure disposal of mechanical drives, but SSDs are a different animal and are likely reusable given some of the suggestions in this thread.

Most hard disks support hardware level encryption and full disk erase at this point. There’s very little need to sledgehammer anything given realistic attacker models.

Both, HDD/SSD encryption in hardware and secure erase have been proven untrustworthy numerous times.

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#32
post #30

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

I think an angle grinder would be more accessible than a press.

Open them, heat treat the disks in a bonfire, use the magnets as fridge magnets (those are quite strong, can fix entire books to the fridge instead of just notes).

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#33
post #7
post #3

Super interested in this and would love to hear about some techniques. Used to work at a HealthTech co. We had an “appliance” that we’d send to doctor offices to integrate with other diagnostic machines on the network. Sometimes we would send out new ones to replace the old. When we got the old ones back, it was always unclear how to purge and recommission SSD/NVME drives. My best attempt was using GNU shred, but it…

The only proper way of disposal is physical destruction, preferrably on site and under observation of inhouse staff. There are contractors you can hire in those: https://shredsupply.com/hard-drive-shredding-trucks/ (no relation, just arbitrary google hit). I'm also unsure as to why you are getting drives back at all, any of your customers should not have any kinds of storage devices leave their site intact. At least…

Oh, we did stuff like this for disposal. The tricky part is drives we desired to recommission.

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#34

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

Delete all the files then "dd" from the random device until the drive is full? Must we always jump straight to the hydraulic press?

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#35
post #34

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

Delete all the files then "dd" from the random device until the drive is full? Must we always jump straight to the hydraulic press?

As mentioned in the article, that's not reliable. Drives have lots of overprovision blocks and there's no way of consistently forcing them to be used; and drives might mark blocks as too questionable/worn to reuse and never reset them.

Also a standard failure mode of SSDs is refusing to accept writes, so you'll have to handle that case.

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#36
post #34

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

Delete all the files then "dd" from the random device until the drive is full? Must we always jump straight to the hydraulic press?

Must we always jump straight to the hydraulic press?

Not always. I suppose it depends on your information security case. If your goal is to secure your kids laptop from the average thief that is heading to the pawn shop, maybe "secure erase" of encrypted drives may be sufficient.

If on the other hand one is protecting intellectual property, customer data and so on, then perhaps that average thief was hired by someone with significant resources. I would wager that a percentage of the people reading this comment are using a work laptop and have some IP on their drive that in the wrong hands could cost billions. Even some of the emails I've seen could do significant damages.

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#37

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

> ...hydraulic press was powerful enough.

Can we repurpose a die press to this task and if so, would a 100 ton AvE die press [1] be powerful enough?

[1] https://www.youtube.com/watch?v=d_LSPX8cNaE

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#38
post #6

This is why you always want to use full disk encryption (FDE). Then it doesn't really matter whether some blocks are recoverable after TRIM. It also doesn't really matter whether the Secure Delete function works. It also doesn't matter whether the very expensive security-buzzword-compliant secure deletion snakeoil software really works. Also, TRIM is only possible with drives that are still in working order. Very oft…

TRIM and FDE isn't perfect though as it leaks information about what parts have been written etc.

And if you turn off TRIM you get a massive performance decrease.

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#39
post #32
post #30

Earlier quoted context omitted.

I think an angle grinder would be more accessible than a press.

Open them, heat treat the disks in a bonfire, use the magnets as fridge magnets (those are quite strong, can fix entire books to the fridge instead of just notes).

Last I checked, SSDs don't have those (see thread title).

Re: How secure is merely discarding (TRIMing) all of a SSD's blocks?

#40

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation . Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydr…

> ...hydraulic press was powerful enough. Can we repurpose a die press to this task and if so, would a 100 ton AvE die press [1] be powerful enough? [1] https://www.youtube.com/watch?v=d_LSPX8cNaE

I suppose provided that we are not punching and instead crushing the SSD chips to dust that would work. Punching holes would leave some chips.
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