XNT Not working

I had a xNT NFC implant on Friday August 10 while I was attending Defcon in the BioHacking area.
I was told it would take a few days (like 48 hours) before I could read my tag. It has been a week and I cannot read it. I tried with different readers and nothing. I can see and feel the tag, especially if I press my fist.
What can I do?

What readers have you tried?

Check this video out.

1 Like

IIRC the xNT is ‘blank’ when you first install it. If you haven’t written any data to it, then a lot of readers will not show it at all when it’s blank? eg. the various iPhone NFC apps won’t find it at all.

Have you tried securing it yet with the DangerousThings NFC android app?

Thank you very much for the answer.
This is all new to me.
I have not tried with the Dangerous Things NFC tool but I will. But first what do you recommend I use to write?

I have no experience with iPhones, but if you are using an Android phone as the reader, here are a few things that might help. I also received my xNT from the BioHacking village at DEFCON 26 and was able to read from the chip after a few hours.

First, I would download three Android apps for your phone:

  • NFC Tools
  • TagWriter by NXP
  • Dangerous NFC
  • Dangerous Things Support Tool (if you run into issues)

NFC Tools and TagWriter can both be used to write data records to your xNT. I prefer TagWriter for writing data since it has some more configuration available and makes it easier to edit data already on the chip. However, for reading data, I prefer NFC Tools since it provides more formatting and capability information. The Dangerous NFC app was a singular purpose - to lock down some memory locations on your chip which could permanently brick the chip if improperly written to.

All three of the above tools will work and read the chip even without any data written to it. I’d suggest the NFC Tools as your first try, as this will show you the serial number and other details of the implant.

When using a phone to read the chip, it is helpful to first test the NFC capabilities of the phone. First, make sure that NFC is turned on (seems obvious, but some phones automatically turn it off if it goes unused). Next, text the phone with a non-implanted NFC chip if you have one available. You may be carrying one is your wallet, such as a student id, work badge, gate badge, etc. Tap the NFC chip to the back of the phone and hold it for a second. You don’t need to keep it there any longer for reading.

When reading from your xNT, the orientation of the phone becomes very important. If you can, locate the exact position of the NFC sensor from your phone’s manual or Google. Samsung phones place the reader near the top (next to the camera), other phones have it closer to the center. Remove the phone case if you have one (at least until you find a good spot/orientation). Try rotating both your arm and the phone in different positions. When trying to find a good position for coupling, my experience has been that I need to remove the reader (phone) from the device for each new attempt. That is, I can’t simply move the phone around while keeping it pressed against my hand. I haven’t confirmed this with technical details, but my guess is that the chip needs to be fully removed from the EM field on each attempted read.

Finally, if you still cannot read the chip, try using a friend’s or coworkers phone. The NXP chips are very durable, and I think it is pretty rare for one to fail.

I’ve tested mine with both a Samsung S8+ and a ZTE Axon 7. The Samsung S8 had a great read range, and once I had the correct orientation and position, I was able to read the chip on around 75% of attempts even through my phone case. The Axon 7 would rarely read the chip with the phone case attached, but when it was removed, I still had around a 50% success rate.