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There used to be an option to delete files securely in older versions of Mac OS X. However, I am unable to find the same in macOS High Sierra 10.13.5.

Is the option removed? If yes, what's the probable reason? As I understand, the command was useful to ensure that data could no longer be recovered from the hard drive.

I am using a Late 2013 15" retina MacBook Pro.

3 Answers 3

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This feature was removed in macOS 10.11 El Capitan. Per the Apple support document About the security content of OS X El Capitan v10.11, it was removed for security reasons.

Finder
Available for: Mac OS X v10.6.8 and later

Impact: The "Secure Empty Trash" feature may not securely delete files placed in the Trash

Description: An issue existed in guaranteeing secure deletion of Trash files on some systems, such as those with flash storage. This issue was addressed by removing the "Secure Empty Trash" option.

CVE-ID
CVE-2015-5901 : Apple

The CVE gives a small paragraph on this issue. From NVD - CVE-2015-5901:

The Secure Empty Trash feature in Finder in Apple OS X before 10.11 improperly deletes Trash files, which might allow local users to obtain sensitive information by reading storage media, as demonstrated by reading a flash drive.

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  • Perfect! Exactly the answer I was looking for. +1.
    – Nimesh Neema
    Jun 6, 2018 at 17:18
  • Wow Apple. "It's broken, so lets throw it away". I think if they took 5min to fix it they could especially since its a great feature. Jun 6, 2018 at 19:09
  • @JBis In reality it is very hard to implement this feature on modern hardware - it is definitely not a "5 minute fix". On an SSD drive you're generally lucky to have a SECURE ERASE command that will safely delete everything on the drive. That's if you're lucky. You won't find a command to delete a byte range nor a single block. Implementing secure erase on top of this without sacrificing major performance or having specialized secondary storage is very, very hard.
    – jksoegaard
    Jul 16, 2018 at 17:32
  • @jksoegaard Just write over the blocks a couple times. Jul 16, 2018 at 17:36
  • 1
    @jksoegaard security.stackexchange.com/questions/12503/… Fair enough. Jul 16, 2018 at 17:43
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If you are concerned about data 'falling into the wrong hands' or just giving/selling your MBP to somebody else, the best practice is to boot into Recovery, use DiskUtility from the Utilities menu to erase the disk with elevated security overwrite passes, then reinstall macOS.

Below is a screen cap of the Security Options available in DiskUtility.

Note: the Most Secure option can take many, many hours to complete, depending on the size and rotational speed of the disk being erased.

SSD drive erasure note from Apple:

With a solid-state drive (SSD), secure erase options are not available in Disk Utility. For more security, consider turning on FileVault encryption when you start using your SSD drive.

enter image description here

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It seems your only options are at the command line. I know of these two:

  1. Install srm via MacPorts

  2. rm -P see man rm for details

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  • Thanks for your answer. However, question concerns with confirmation of removal and the reason for the same.
    – Nimesh Neema
    Jun 6, 2018 at 17:08
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    No problem. I thought it did answer the "is it removed" question via "only options are command line". And as for reasons, :) who knows, really? But I'm happy you got what you were looking for.
    – Seamus
    Jun 6, 2018 at 17:36
  • The reason files on SSD drives can’t be securely erased is because their controllers implement wear leveling so that writing a block to an SSD does not overwrite the old block, instead the data is written elsewhere and a pointer is set to the new data. askubuntu.com/questions/794612/… Sep 24, 2022 at 6:41
  • The rm(1) man page says: "-P This flag has no effect. It is kept only for backwards compatibility with 4.4BSD-Lite2." Aug 16, 2023 at 21:18
  • @200_success: But that's NOT what it said in. the January 28, 1999 version of the man page which I had on my macOS Mojave version which was current when the question was answered.
    – Seamus
    Aug 17, 2023 at 7:49

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