McDonald's Japan: a mail setup error exposed 8,989 customer email addresses to other recipients of app sign-up emails

1. 2025-03-14 12:00

   Sign-up confirmation emails to customers who registered in the official app on March 12 and 13 were sent with other customers' addresses in the To field because of a mail delivery system setup error. It happened around 12:00 to 13:00. [1] [2]

2. 2025-03-17

   It learned of the problem from customer inquiries and reported it to the Personal Information Protection Commission. [1]

3. 2025-03-19

   It announced the incident. [1] [2]

Each email listed up to 500 addresses, affecting 8,989 addresses in total. It said no personal data other than email addresses was exposed, and asked recipients to delete the email. [1]