looking into how to properly erasing data from solid state devices is quite the topic with a different answer from just about every webpage I read. I understand there are issues with wiping data from SSDs due to the efforts of wear leveling, but now I read that eMMC supports TRIM, does that mean that eMMC storage will be just as complicated to data wipe as SSDs are?

  • I can't comment on the actual difficulty of wiping data from the underlying electronics, but I will say this - the only way I would feel secure that data on ANY common storage medium is unrecoverable is if it's ground into a fine powder or completely melted into a liquid (and maybe stirred a bit for good measure). – childofsoong Mar 8 '16 at 19:31
  • 1
    @childofsoong - Last time I melted a hard drive, I forgot to stir it, and consequently my friend in data recovery was able to reconstruct my cat videos. – TTT Mar 8 '16 at 22:24
  • @TTT I hope they were good cat videos! – childofsoong Mar 8 '16 at 22:44
  • @childofsoong - Humor aside, what options are there to ground it into powder, melt it, etc while remaining cost effective? – Motivated Dec 27 '18 at 4:11

I don't believe TRIM has a major effect on memory clearing; it's wear-leveling that's the main issue, as it means the OS could 'overwrite' data while it still exists on the physical media. TRIM is just telling the drive that a certain area isn't needed, and the drive can do what it likes with it.

SATA drives (including SSDs) have the ATA-SE commands, which allow you to tell the drive to delete everything on it, including any 'reserve' areas. Whether this is implemented correctly is another question, though. I don't think eMMC drives have this.

As eMMC drives are generally a single package, it's harder to remove the flash chips (or solder onto the pads directly) and read the flash without going through the controller - this could make it slightly more difficult. It's probable that eMMC controllers have debug modes that allow read-out of the flash, though.

I'd have to agree with childofsoong that you can't be certain that it's all gone without complete destruction.

  • Is there a definitive list of drives that respect the ATA Secure Erase function/feature? It's my understanding (albeit limited at this stage) that not all vendors may fully implement it as per the standard. – Motivated Dec 27 '18 at 4:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.