"Security researchers have demonstrated that an expired credit card is not as dead as most cardholders believe. A study from the University of Massachusetts Amherst reveals a practical NFC relay attack dubbed “Zombie Card” that revives expired Visa contactless cards, allowing them to complete real purchases at point-of-sale terminals across multiple US banks. The discovery is simple: card expiration in EMV contactless payments is enforced as a transaction policy check performed by the terminal, not as a cryptographic fact in the card itself."