A lot of people assume this, but with contactless EMV there is a whole transaction flow between the card and the reader going on.
You know those 4 lights on a contactless card reader? They indicate different transaction stages between the card and the terminal. I don’t find them that useful because it’s so fast they all appear to light at the same time, but that’s what they are!
If they were just passive tags, they wouldn’t be very secure, they have cryptographic processors onboard with private keys that can sign stuff for the terminal and your bank. The specs for the interaction are all public if you’re interested (I wouldn’t be!) and lookup contactless EMV.
You know those 4 lights on a contactless card reader? They indicate different transaction stages between the card and the terminal. I don’t find them that useful because it’s so fast they all appear to light at the same time, but that’s what they are!
If they were just passive tags, they wouldn’t be very secure, they have cryptographic processors onboard with private keys that can sign stuff for the terminal and your bank. The specs for the interaction are all public if you’re interested (I wouldn’t be!) and lookup contactless EMV.