A Factory Reset doesn't delete everything

[nullBot]

Hard Proof That Wiping Your Phone Doesn't Actually Delete Everything

If some of you do have sensitive data on your phone, it makes you wonder if the old phone would be better of destroyed instead of selling/giving it away.

 

[funkylogik]

What if you use a dummy file generator to overwrite everything?

 

[jhawkkw]

A factory reset while nice, is not as complete as flashing the factory image. That will physically re-write every partition with a blank copy that the image comes with. It's the one sure fire way to wipe out everything.

 

[Hadron]

Or, as even the press suggested, turn on the option to encrypt your storage then do a reset. The key is deleted, and if you do a forensic recovery the data are still encrypted.

 

[John Bean]

At least with solid state storage the data is gone after overwriting, unlike magnetic media where residual data can still be read from the edges of the tracks even after erasure and overwriting unless this is done many times with different data.

Honest people don't tend to get paranoid about it and usually do enough to make it hard (but not impossible) to recover deleted data. Opportunists tend to go for the easy targets unless they know with certainty that there is profit in digging deeper, police and security services are another matter of course - hence the "honest people" comment.

 

[nullBot]

Thanks for the replies everyone, very good ones.

Even though we are honest people we still don't want people trying to retrieve our data whether it's contacts, emails, sms messages, photos and etc after a factory reset. It's a privacy issue.

In a recent podcast of All About Android, they said the reason google android doesn't use a more secure erasure of the data is because it takes longer to do a bit-by-bit overwrite of the data and it also reduces of the lifespan of the flash memory.

** The discussion of the factory reset in the episode starts at the 5 minute mark. Just drag the time line and you're good to go.

Even though the default factory reset is faster at deleting files it is not secure. In my opinion, google android should implement an option or checkbox to the factory reset to allow us to choose how we want to do our factory reset of our devices:

• The default factory reset ( fast but not secure )
• A slower bit-by-bit overwrite and deletion of the data and possibly shortening the lifespan of the flash memory ( more secure )

 

[mrex]

Hard Proof That Wiping Your Phone Doesn't Actually Delete Everything

If some of you do have sensitive data on your phone, it makes you wonder if the old phone would be better of destroyed instead of selling/giving it away.

Better to encrypt than destroy and then selling or giving away.

I havent encrypt my phone, Note 10.1, because i read from somewhere that SPen is slower after the encryption.

 

[Digital Controller]

Honestly the only way I have ever gotten rid of my device is to my carrier, and I am not really worried about anything after that.

 

[SiempreTuna]

it takes longer to do a bit-by-bit overwrite of the data and it also reduces of the lifespan of the flash memory

.. and I'm sure I read something recently about research that proved 'secure erase' doesn't always work with flash anyway

Hadron's idea seems to be the best bet, though even with that there's the miniscule, but still theoretical, chance that the encryption key would still be recoverable.