Mobile phones are helping millions of low-income customers to access financial services for the first time, but they are also exposing them to new cyber threats they could never have imagined. The Serianu 2017 Africa Cyber Security Report estimates that cybercrime in mobile-based transactions costs businesses $140 million per year in Africa. Why is this becoming more common? And what can providers and policy makers do to prevent it? The author offers some simple measures that providers and policy makers can adopt to protect other mobile financial services users from cyberattacks.