Mirae Asset Securities, South Korea’s largest brokerage, said Saturday that intruders had gained unauthorized entry into its systems, exposing information connected to around 39,000 people, according to Yonhap and The Korea Herald.
- Mirae Asset Securities disclosed on Saturday that data linked to roughly 39,000 people had been exposed, according to Yonhap and The Korea Herald.
- About 3,800 customer account numbers were among the compromised records, the firm said.
- Information on more than 35,000 current and former staff and contractors — including names, ID numbers, emails, phone numbers and passwords — was also exposed, Yonhap reported.
- The firm said it cut off the affected access points and alerted three financial regulators after spotting the intrusion.
- Korea Times noted the incident followed a similar leak days earlier at sister firm Mirae Asset Life Insurance, part of a broader wave of financial-sector breaches.
What happened
The firm said outside parties broke into two separate systems on consecutive days — first its mobile authentication login tool, then an internal network — allowing them to pull data out. Roughly 3,800 customer account numbers were taken, Yonhap reported, alongside records belonging to more than 35,000 people connected to the company as current or former staff members and outside contractors.
For that second group, the exposed material reportedly spanned full names, internal staff identification numbers, contact emails, mobile numbers and login passwords, according to Korea Herald and Korea Times accounts.
Why it matters
Mirae Asset holds a leading position among Korean brokerages, so an intrusion of this scale raises concerns about how well large financial institutions are guarding both client and workforce data. Exposed passwords and contact details can open the door to follow-up scams such as impersonation attempts or phishing messages aimed at those affected.
Our read: the fact that both customer and internal employee systems were breached within a two-day window points to a coordinated effort rather than an isolated glitch, underscoring why regulators are watching the financial sector’s cyber defenses closely right now.
Background
Mirae Asset told Yonhap it noticed unusual activity coming from outside IP addresses, moved quickly to seal off the compromised pathways, and switched on its internal emergency protocol. It also notified South Korea’s main financial watchdogs — the body overseeing financial policy, the one supervising financial institutions, and the agency responsible for personal data protection — about the incident.
According to Korea Times and Yonhap, this episode came only days after Mirae Asset Life Insurance, a related firm within the same corporate group, reported a comparable leak of its own. Citing the Financial Services Commission, Yonhap noted that over the past month more than 470,000 personal records have leaked across 37 financial firms, with stolen funds estimated around 1 billion won, roughly $745,000. Regulators said that since late September, 40 separate leak cases have surfaced at those 37 companies, covering four commercial banks, five financial investment firms, three insurers and five savings banks.
What to watch
Whether Mirae Asset’s containment steps prevent further misuse of the leaked credentials remains to be seen, and regulators may release more detail as their review continues. Given that several financial firms have now reported similar intrusions within weeks of each other, further disclosures from other companies in the sector would not be surprising.
This suggests authorities could move toward tighter rules on how brokerages and insurers secure login systems and internal databases, though no such measures have been announced yet based on current reporting.
Frequently asked questions
How many people were affected by the Mirae Asset Securities breach?
The company said data tied to about 39,000 people was exposed, including roughly 3,800 customer account numbers and records for more than 35,000 staff and contractors, according to Yonhap.
What kind of information was exposed?
For employees and contractors, the leaked items included names, staff ID numbers, email addresses, phone numbers and passwords, per Korea Herald and Yonhap reporting.
What has Mirae Asset done since discovering the breach?
It said it shut down the compromised entry points, triggered its internal crisis response procedure, and informed Korea's financial oversight bodies, according to Yonhap.
Sources
- The Korea Herald: Personal info of some 39,000 leaked from Mirae Asset Securities
- The Korea Times: Leak exposes personal info of 39,000 Mirae Asset Securities customers, employees
- Yonhap News: (LEAD) Personal info of some 39,000 leaked from Mirae Asset Securities
- Yonhap News: Mirae Asset says data breaches exposed customer, employee information
This article was prepared with AI assistance from the reports listed above and automatically checked against them. See About for how we work.