Total Registration LLC, a third-party service provider for exam registration, experienced a data security incident due to a misconfigured Amazon S3 file storage server. The misconfiguration allowed potential unauthorized access to student registration information (names, dates of birth, addresses, phone numbers, student IDs) for students who registered for AP exams between June 2016 and April 2019. The issue was discovered on April 11, 2019, by a security researcher and remediated by April 12, 2019. No evidence of actual unauthorized access by third parties was found. Social Security numbers, credit card data, and medical information were not involved.