Post #4074349
2026-07-24 21:41 UTC
@rrb@infosec.exchange @evacide@hachyderm.io Wear levelling will can make a filesystem level erase not wipe data, but devices can have device level secure erase commands too.
Replies (1)
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@bob_zim@infosec.exchange 2026-07-24 22:30
@ocnurb@woof.group @rrb@infosec.exchange And note most SSDs have two levels of secure erase. One takes a few microseconds to flush the key used to encrypt the data on the flash. This is secure unless the SSD vendor lies, but it leaves the data in place, so pages still need to be erased before they can be written. This is what phone wipes do, but desktop SSDs can typically do it, too. The other type uses dedicated circuitry in the flash chips to set all the pages (including faulty pages and spare pages) back to a neutral state. This takes several seconds and more power, but it restores out-of-the-box performance. This is common on desktop SSDs.