iPhone Erasing iPhone contents so it's not retrievable with software

[Mac2c]

Hi, I want to return a phone back to an ebay seller but I have sensitive information on it.
I'm aware that you can retrieve data even after erasing the iPhone contents via the "Erase all contents" option. There are youtube videos of people using software to retrieve photos and notes etc. I can't have that.

What's a good way to go about this so my information without a doubt cannot be retrieved by any software tools?

Thanks!

 

[Armen]

Hi, I want to return a phone back to an ebay seller but I have sensitive information on it.
I'm aware that you can retrieve data even after erasing the iPhone contents via the "Erase all contents" option. There are youtube videos of people using software to retrieve photos and notes etc. I can't have that.

What's a good way to go about this so my information without a doubt cannot be retrieved by any software tools?

Thanks!

DFU restore. Google it.

 

[C DM]

Hi, I want to return a phone back to an ebay seller but I have sensitive information on it.
I'm aware that you can retrieve data even after erasing the iPhone contents via the "Erase all contents" option. There are youtube videos of people using software to retrieve photos and notes etc. I can't have that.

What's a good way to go about this so my information without a doubt cannot be retrieved by any software tools?

Thanks!

https://forums.macrumors.com/threads/wiping-a-phone-before-reselling-safe.2124334/

 

[rorschach]

DFU restore. Google it.

Restoring doesn't erase your data. You need to do erase all content and settings for that.

See: https://help.apple.com/iphone/11/#/iph1624229a

Important: Restoring iPhone to factory settings using iTunes deletes all your content and settings, but doesn’t erase it. Deleted information can’t be accessed through the iPhone interface, but it remains on your device. For information about erasing all content and settings, see Erase iPhone.

With encryption it's basically impossible to access, but if you want to be really safe...

 

[Mlrollin91]

Restoring doesn't erase your data. You need to do erase all content and settings for that.

See: https://help.apple.com/iphone/11/#/iph1624229a



With encryption it's basically impossible to access, but if you want to be really safe...

I think you are confusing DFU restore and restoring from a backup. A DFU restore completely erases and reinstalls iOS. An erase content and settings only removes your information, but does not reinstall iOS. DFU is the most secure way to wipe the device.

A DFU restore is not an "iTunes restore as new".

 

[Mac2c]

I think you are confusing DFU restore and restoring from a backup. A DFU restore completely erases and reinstalls iOS. An erase content and settings only removes your information, but does not reinstall iOS. DFU is the most secure way to wipe the device.

A DFU restore is not an "iTunes restore as new".

I googled DFU mode to see if it erases everything in such a way that no data can be recovered using a software recovery tool, but I couldn't find it.

So my question then is, does DFU mode ,without a doubt, erase everything on the HD so that no data can be recovered with special tools? I've seen Youtube videos where Notes and photos are recovered using such tools, so ideally looking for a definitive answer.

Thank you!

 

[NoBoMac]

• Erase all contents
• Set a passcode when restarts
• Erase all contents
• Leave at welcome screen after second restart

If you had set a passcode initially, the phone's memory was encrypted with a random key. Erase will wipe the original key and the second passcode will re-encrypt with a different random key. Second erase will wipe that key. So, your memory has now been encrypted twice with an unrecoverable key.

Additionally, if you had an initial passcode, each file written to the device was encrypted with its own encryption key. And that encryption key was encrypted with a different key. And the encrypted key is encrypted with yet another key. And when the phone is erased, all those keys are wiped.

So, needlessly stressing. Guessing those videos are of early versions of iOS or were not passcode protected devices. Or utter nonsense.

https://www.apple.com/business/docs/iOS_Security_Guide.pdf

ADD: if don't want to get into the details that are in the white paper, a key passage in the doc:

Erase All Content and Settings
The “Erase all content and settings” option in Settings obliterates all
the keys in Effaceable Storage, rendering all user data on the device cryptographically inaccessible. Therefore, it’s an ideal way to be sure all personal information is removed from a device before giving it to somebody else or returning it for service.

 

[Broken Hope]

Erase all content and settings destroy's the encryption key, I really don't see how anything can be recovered from an erased phone.

 

[charlituna]

I googled DFU mode to see if it erases everything in such a way that no data can be recovered using a software recovery tool, but I couldn't find it.

ultimately there is no way to say that it's utterly impossible to retrieve data on an intact drive. I mean if you really wanna make sure your data is gone you would keep to break open the phone, dip the drive in liquid, smash it into pieces and then melt the pieces into slag.

but a DFU restore is going to make it frakking hard to recover anything. that's part of why data recovery shops start the fees at $1000 for an iPhone.

i suppose if you wanted to try to really muck up the chances you could try the old trick of filling the drive with random data and doing another restore. 4-5 times was always the suggested iteration of that one.

 

[cobracnvt]

• Erase all contents
• Set a passcode when restarts
• Erase all contents
• Leave at welcome screen after second restart

+1 on this approach