Researchers find a loophole that lets expired credit cards make unauthorized payments

A team from the University of Massachusetts Amherst has shown that a contactless credit card keeps working past its printed expiration date, even after the cardholder gets a replacement. They named it the Zombie Card attack and presented the findings at USENIX Security 2026. The question behind the loophole “This work is motivated by documented patterns of improper expired card handling. Although…