South Korea's Financial Supervisory Service has launched an emergency on-site inspection of Mirae Asset Securities after the brokerage disclosed that personal information linked to about 39,000 people was exposed. The affected group includes approximately 3,800 customers and 35,255 employees, making the incident the largest leak reported in South Korea's financial investment industry this year by the number of people involved. The FSS is examining the scale of the damage, how the breach occurred and whether consumers suffered losses. The inspection's duration will depend on the findings and could be extended if the case is deemed serious. The incident follows unauthorized access to the brokerage's mobile web phone-authentication login service and groupware on Nov. 4 and Nov. 5. Account numbers, names and employee identification numbers were exposed, while resident registration, passport, driver's license and alien registration numbers were not. No direct financial losses have been confirmed, and key systems and financial services remain operational; the company has warned customers about phishing and smishing. The regulator is also focused on a succession of attacks involving four Mirae Asset Group affiliates: MIRAE ASSET Life Insurance on Oct. 26, followed by Mirae Asset Global Investments, Mirae Asset Energy Infrastructure Asset Management and Mirae Asset Securities. A person familiar with the matter said the attacks could have formed a coordinated campaign targeting the group. Mirae Asset Securities managed 693.3 trillion won in client assets in the first half of the year, increasing the potential significance of the breach for the group and the wider brokerage sector. Concerns have also grown as Mirae Asset accelerates artificial intelligence transformation under its Mirae Asset 3.0 strategy and seeks to establish a groupwide AX framework. In a reorganization on the 5th of this month, the brokerage elevated its information-protection unit. The broader executive reshuffle also included 20% of promoted executives specializing in AI transformation, digital technology or information security, nominated Vice President Noh Yong-woo as CEO of Digital X, formerly Korbit, subject to Financial Intelligence Unit approval and a shareholders' meeting, and appointed Woo Shin-je to lead Mirae Asset Energy Infra Asset Management.