Card Encoding

Securing a Mifare card

To secure and protect from card cloning and also possible number duplication it is important to read from the smart cards storage rather than the card serial number (CSN).  The card serial number has no security measures to protect from exploitation.

It has become more and more common to obtain cards which allow the CSN to be edited and therefore a card to be copied

Sensor readers will read multiple card technologies dependent on internal aerial:

- Mifare Classic

- Mifare Plus 

- Mifare Ultralight

- Mifare Desfire

- NFC (Sensor Mobile Key)

- Fudan CPU

- CEPAS

- ICODE

- ICLASS (UID)

- SONY

- GPROX

- EM

- HID

- ATMEL

The Sensor DF cards and readers use Mifare Desfire with AES encryption and this is what we would always recommend using to offer the highest security.

The Mifare Classic type card is quite wide spread and commonly used for public transport systems around the world. There is a known vulnerabilities on this type of card as it uses static keys. the card is divided into sectors and if any of these sectors are using the default key opens up the card to being copied.

Sensor Classic Andriod application

When purchasing blank Mifare cards, it's crucial to encode them properly to enhance their security. Sensor Access provides SF and DF cards, which come pre-encoded to match a default key used by the reader.

We offer a simple Android application that allows you to encode your blank cards. When encoding your card, it is essential to ensure that the key you use matches the one programmed into the reader.

The encryption keys on Sensor readers can be updated using a configuration card, which should be presented to the reader within the first 5 seconds after powering it on.

you can obtain configuration keys and key files from sensor access. Each new key will be chargeable.

To obtain this application you must be invited by sensor access.

To use the application you must obtain a key. This key will need to match the key being used on the SF/DF reader. The key comes as a P12 file and stored in the phones secure storage.

Once in the application you have the option to read format or encode the key. If the card is already encoded you must have the same key otherwise you will get a failure to communicate message when presenting the card to the phone.

To match the default sensor Hexadecimal format the bit offset must be set to 2 as in the screen shot above.

For further information please contact 

[email protected].uk