It turned out that computer system failures occurred particularly often at Fintech-based securities firms such as Toss Securities and Kakao Pay Securities. Although they are new securities firms touting IT prowess, there is an assessment that their internal controls and system stability are insufficient compared with their rapid external expansion.
According to data submitted by People Power Party Rep. Lee Heon-seung, a member of the National Policy Committee, from the Financial Supervisory Service on the 23rd, over the past five years (January 2020–August 2025) there were a total of 474 computer system failures at securities firms, with damages amounting to 26.7 billion won.
Under current supervisory rules, an electronic financial incident means a delay or suspension lasting 30 minutes or longer; or 10 minutes or longer affecting 10,000 or more users; or a case in which errors occur in computer data or programs.
By number of incidents, NH Investment & Securities and Toss Securities had the most with 42 each, followed by Kakao Pay Securities with 41. They were followed by Shinhan Investment & Securities, Samsung Securities, Kiwoom Securities, and LS Securities. By amount of damage, large firms ranked at the top. Korea Investment & Securities had the most at about 6.5 billion won. Next were Kiwoom Securities with 6.1 billion won and Mirae Asset Securities with 4.1 billion won in damages.
However, in terms of frequency, Fintech-based securities firms stood out. Since its launch in 2021, Toss Securities has had 42 computer system failures over four years. Its operating period is shorter than that of major firms, but it recorded the same number as NH Investment & Securities. Kakao Pay Securities also saw a steady increase in incidents since 2020, showing a higher incident rate compared with large securities firms.
Toss Securities recorded seven incidents in 2021, its first year, then 14 each in 2022 and 2023, ranking first in computer system failures among securities firms for two straight years. The number fell to two last year and five this year, but concerns about stability remain high, including a continuous outage lasting 86 hours last year.
Computer system failures at Kakao Pay Securities are also on the rise. There were four in 2020, one in 2021, and five in 2022, then nine in 2023, and 11 each in 2024 and 2025.
Toss and Kakao quickly increased their market share by prioritizing a convenient user interface (UI). However, there is criticism that stable computer systems and internal control infrastructure have not kept pace with their growth speed.
A financial investment industry official said, "Fintech-based securities firms have rapidly expanded their markets by touting differentiated MTS and HTS, but their operational know-how and risk management framework for IT systems are inevitably relatively lacking," and added, "As financial authorities have signaled a stern response to computer system failures, the industry is paying more attention to IT infrastructure investment and accident prevention."
Financial authorities are also moving proactively to prevent computer system failures. Since August, the Financial Supervisory Service has been preparing a "comprehensive plan to enhance the safety of capital market transactions" and plans to check measures such as executive-level meetings and companywide improvements to IT internal controls for high-risk securities firms.