The CVV code is in your VISA magnetic stripe and can only be read when swiping the card. Was it leaked by a stolen brush?

There is also CVV2 code, which is usually printed in italics by the card issuer near the signature column, and the last three digits are CVV2 code.

If CVV or CVV2 has been leaked, please contact the issuing bank to report the loss in time. As long as the main account number changes, the risk can be reduced.