Day1Company suffered a personal data breach after an unauthorized intrusion into its IT management system exposed the personal information of instructors and customers across multiple online education platforms, including Fast Campus, Coloso, Zerobase, MyLight, Newspresso, Respeak, Shiny English, and Wannaspeak. The company stated that the intrusion occurred on May 9, 2026, and may have affected between several hundred thousand and up to 1 million individuals. Exposed information reportedly included names, phone numbers, account numbers, resident registration numbers, and credit card numbers. Day1Company detected the incident on June 8, reported it to relevant authorities, and is currently investigating the full scope and impact of the breach.