Hidden silent implant


Is there a chip that won’t react to reader nearby unless receives passphrase first?

I’m wondering about posibility of hiding encrypted crypto seed on nfc tag, and i dont want to share it with any device that will comes close to it.

Random read attempts should be ignored as if no chip was there, unless chip receives specific request first.

If not, how else would You solve this?

I’d encrypt it with a password I store in my brain.

I’d maybe put it in the bytes behind the NDEF aswell so some readers will miss it.

How will the reader know to send the passphrase? If it just sends the passphrase constantly then anyone can capture the passphrase.

Your best bet would be to encrypt the data.


Knowing very little about chip nor reader design, you MIGHT be able to do something with Vivokey Apex and a specialized reader. The reader tries to read something normally before the Apex responds asking for a password or encrypted data that the Apex recognizes as the Apex, enters the password, and you get your data.

That said, please take what I say here with a grain of salt. I’m a CS student, by no means a pro nor do I have any experience with the reader-side of things beyond lightly modifying some PcProx readers.

A rickroll before the encrypted text should be a good distraction IMHO.

Of course, you can roll your own solution using a chip that can handle encryption but developing it will take time and if you’re not careful, you could end up with something that’s less secure…

Of course, if DT doesn’t have the chip you want, Amal can turn some types of fobs and cards into flex implants. But this would be an extreme case for what you are doing…

I mean there’s basically already an app that just saves data in the VivoKey KVS with auth. Julio made a video explaining how that works, in detail. It doesn’t sound like too much work too encrypt and decrypt it and you could set Spark 2 to a rickroll aswell…

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I didn’t know the Spark 2 supported NDEF.

*Starts rethinking his life choices.

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Thank you for replies.

Apex Max (when and if it releases) with custom java aplet and custom Android reader app could work in theory?

Like user writes passphrase in app and it is emited via nfc. When Apex reads correct passphrase responds with payload. Without passphrase does not return anything.

It can’t but it has a url where you can control the redirect