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@om_patel5 built a desk-mounted standalone Touch ID sensor for Mac…

Brief

A standalone Touch ID sensor for Macs, built by @om_patel5 and published 2026-08-06, emulates a smart card so macOS receives cryptographic signatures (appearing as a "PIN" login). The chip only signs after a locally verified fingerprint, but the fingerprint-to-chip link runs over two unencrypted wires, allowing physical attackers to impersonate the sensor; the builder sealed his desk unit in black epoxy and open-sourced the design.

Why it matters

@om_patel5 built a desk-mounted standalone Touch ID sensor for Mac mini/Studio/iMac that emulates a smart card (the same tech as credit cards, SIMs, and hardware security keys); macOS receives cryptographic signatures and shows the login as "PIN" because it never gets a password.

Key details

  • The device gates smart-card signing behind a fingerprint: the chip refuses to run the smart-card protocol until a valid print is presented, but the fingerprint sensor talks to the chip over two unencrypted wires, so anyone with physical access could impersonate the sensor and authorize a login.
  • The builder keeps the unit on his desk, sealed it in black epoxy to deter tampering, open-sourced the project, and published the demo on 2026-08-06.
Source evidence

SOMEONE BUILT A STANDALONE TOUCH ID SENSOR FOR YOUR MAC

macbooks have touch id built into the keyboard, but if youre on a mac mini, studio or imac your only option is buying apples magic keyboard

he made a dedicated sensor that just sits on the desk instead

his mac doesnt even think its a fingerprint reader

> it emulates a smart card, the same tech as your credit card, your sim, and hardware security keys
> a smart card holds a secret that never leaves the card. the mac sends it a random challenge, the card signs it, the mac verifies the signature
> so the mac never receives a password, it just gets cryptographic proof the card holds the secret
> then he gates the whole thing behind your fingerprint. the chip refuses to run the smart card protocol until a valid print is presented
> your login screen literally says pin instead of password because macos has no idea whats actually going on

however the catch is the fingerprint sensor talks to the chip over two unencrypted wires, so anyone with physical access could impersonate the sensor and authorise a login

but everyone asks how secure is it, nobody asks how secure does it need to be

this thing sits on his desk in his house and never leaves, so he sealed it in black epoxy to make tampering harder and called it done

AND its open source too

Video