RFID with the Proxmark3

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The proxmark is an RFID security tool that is capable of reading from and writing to a range of different RFID cards. Usually RFID readers and writers come from a hardware vendor that only works with a specific frequency and card type. This is much the same as WiFi radios, they are only designed for a narrow frequency set and to talk a single protocol. The proxmark is a swiss army knife of RFID. You could also think of it as a software-defined radio for RFID. Like a lot of security testing tools, it is designed with the expert in mind and does not come with a point and click GUI

Start by plugging the Proxmark into your computer and connecting it through to your Ubuntu virtual machine.

Introducing the Proxmark3 RDV4
Indroducing the Proxmark3 RDV4


Perform a:

sudo dmesg | grep -i USB

to check that the proxmark looks visible oven USB. Then:

cd proxmark3

Using the Proxmark 3

Then you can start proxmark with

./pm3

Have a play with the following commands:

[usb] pm3 --> hw status

Who and what is Iceman? Can you find the Github repo?

[usb] pm3 --> hw version

What is the embedded processor and instruction set of the Proxmark you have?

[usb] pm3 --> hw tune

What frequency is Low Frequency RFID? What Frequency is High Frequency RFID?

To get an overview of the available commands for LF RFID and HF RFID:

[usb] pm3 --> lf 

How many low frequency tags are supported?

[usb] pm3 --> hf

How many high frequency tags are supported?

To search quickly for known LF or HF tags:

[usb] pm3 --> lf search
[usb] pm3 --> hf search

Tune for LF and HF

Move the card around and watch for the voltage to drop
Move the card around and watch for the voltage to drop

If you are having trouble getting a read try

lf tune --mix

OR

hf tune --mix

Here you are looking for the card to "couple". So the lower the voltage drops the more the RFID card is drawing from the system and the better the read you will get.

Play with the practice RFID cards

Take 4 RFID tags/cards from the practice cards for each of them, can you identify:

  • Is this a low-frequency or high-frequency tag?
  • What type of card is it, and which group might have manufactured it?

Start your Skills Test here

At this point, you are ready to start your skills test. Use the materials below as well as your tutor as a guide to complete your skills test as a group.

LF T5577 card

Low Frequency capability
Low Frequency capability

If you think this could be a T55xx you can run a:

lf t55 detect

This should return the type of card. You can then examine the datasheet here: http://ww1.microchip.com/downloads/en/DeviceDoc/ATA5577C-Read-Write-LF-RFID-IDIC-100-to-150-kHz-Data-Sheet-DS70005357B.pdf

You can try to read all of the blocks with the following command:

lf t55xx dump

This should dump all the blocks on the t55xx card

HF Mifare

High Frequency capability
High Frequency capability

High Frequency Mifare cards are also super common. You should be able to detect one with the standard:

hf search

If you find a tag record what sort of tag you think it could be. Try just typing:

hf

This should reveal all the different types of cards that can be read. Try to correlate the previous info from hf search against the info that you see in the image to the right. You could now try a:

hf mfu info

If that reveals that it is a gen 1a then you could consider executing a command frame the following block:

Generic Mifare commands
Generic Mifare commands

Often the proxmark software will prompt you for a command to try.

hf mfu dump

You would then open a separate terminal and:

xxd hf-mf-ABCEDFIG-dump.bin

This should provide you with the binary output of the card.