Attackers used a fake regulator account to breach Korea's Financial Security Institute assessment system, taking files from 48 financial firms

KBS and Yonhap report that the information protection assessment support system of Korea's Financial Security Institute was hacked on November 9, 2026; the institute confirmed some data leaked, blocked the system and reported to the Financial Services Commission, and files from about 48 financial firms, some 130 in total, are estimated to have leaked ^[3][1]. Yonhap and Boannews report the attackers abused a flaw in the permission approval system to create a fake account with Financial Supervisory Service privileges and download data, including about 200 administrative forms, about 300 personal records such as names and birth dates and about 350 masked user records, while the institute says no FSS credentials leaked and no resident registration numbers or system diagrams were taken ^[1][2]. Financial firms that submitted assessment material should check whether FSI has notified them and review their submitted forms for unmasked personal data, since Boannews says some smaller firms uploaded unmasked data ^[4][2].

Industries mainly affected: Finance