Encrypting SD Card?

Marzipanogram · 1 Jun 2016 at 14:00

I've tested out encrypting a SD card in an Android tablet.
If I transfer the card to my Android phone, it's obviously encrypted and unusable.
But, if I transfer the card to a PC, all the contents are visible.

What is the point of encrypting, when it doesn't protect data?

Myshra · 1 Jun 2016 at 14:24

Can you run through how you're reading the card. Is it through the tablet which is connected to the PC via USB cable over MTP protocol?

Marzipanogram · 1 Jun 2016 at 14:31

Myshra said:
Can you run through how you're reading the card. Is it through the tablet which is connected to the PC via USB cable over MTP protocol?

I took the card out of the tablet and connected it to the PC via a card reader.
To simulate the tablet being lost/stolen and to check how secure the data would be on the card.

Orcvader · 1 Jun 2016 at 23:44

What Android tablet is it?

Marzipanogram · 2 Jun 2016 at 00:01

Orcvader said:
What Android tablet is it?

The Samsung Tab S2, running MM 6.01 (rooted).

Orcvader · 2 Jun 2016 at 08:45

When you access the SD card on the PC, and see the files, can you actually open them?

Marzipanogram · 2 Jun 2016 at 10:30

Orcvader said:
When you access the SD card on the PC, and see the files, can you actually open them?

Yes, I can see them, open, edit and save.
I created a text document on the tablet. Put the card into my PC.
Then edited the file, saved it. Placed the card back into the tablet and could see the changes I'd made.

Orcvader · 2 Jun 2016 at 12:22

The only thing I can think of is the device not actually encrypting the SD card. Can you take a screenshot of the encrypting options?

Marzipanogram · 2 Jun 2016 at 16:45

Orcvader said:
The only thing I can think of is the device not actually encrypting the SD card. Can you take a screenshot of the encrypting options?

Yes, I think you're right.

Below are two screenshots on the same image file.

It shows "Decrypt" and "Encrypt", because the encrypted card was put back into the tablet. Usually the only option would be "Encrypt".
After the left side image, I'm prompted the enter a password/pattern as confirmation I want to continue.
The image on the right shows me decrypting in this case, but obviously it would say encrypting and would take 20 - 30 mins to complete.

The weird thing is, if I put another card (2GB) into the tablet that hadn't been encrypted, a dialogue box popped up asking to "Decrypt" or "Encrypt" before I could use the card.

If I choose either option, it decrypts or encrypts in a few seconds, there's no progress bar (probably because there's virtually no data on it).
So, I don't think it's properly encrypting.