A task from justCTF 2024 Finals created by Disconnect3d and NikoĊ
To play the challenge, you need a NFC card with >300B memory. Click on 'Start scanning' and find a way to buy the justCTF flag without checking out the source code (it wasn't possible to do so onsite). For sources see here and to see how it looked like onsite, see this presentation.
Note: The website uses the Web NFC API which is experimental and works (only?) in Android Chrome >=89