South Korean megachurches Yoido and Sarang suffer massive AI-linked data breaches

An internal audit at Yoido Full Gospel Church, the world’s largest Protestant congregation, revealed that names, birth dates and other personal information for approximately 850,000 members may have been leaked. The review was launched after the Korea Internet and Security Agency alerted the church to a suspected breach on Tuesday afternoon. Cybersecurity firm Oasis Security uncovered data from both Yoido and Sarang Church on an external server, with system logs suggesting the attackers employed artificial-intelligence tools.

In Sarang Church’s case, records of about 89,000 members and 286 employees, including the senior pastor, were reportedly taken in August. The churches responded by shutting down external access, resetting server passwords, and planning to replace firewalls and address vulnerabilities. Police have initiated a full investigation into a series of AI-assisted hacking incidents that also targeted banks such as Shinhan Bank. The breaches highlight growing cyber threats to large religious organizations in South Korea.