South Korea Cyberattacks Hit Daishin, Mirae Asset and Bithumb
Daishin Securities exposed data on 38,490 customers as Mirae Asset and Bithumb reported breaches, prompting wider South Korean cybersecurity system checks.
Summary
South Korea’s financial sector suffered another cyberattack wave on October 28, 2026, affecting Daishin Securities, Mirae Asset Global Investments and crypto exchange Bithumb. Daishin said names, email addresses and mobile numbers belonging to 38,490 customers were exposed. It notified affected customers, is cooperating with authorities and will provide legally required compensation for losses. Mirae and Bithumb separately disclosed incidents on Wednesday but have not confirmed customer data theft.
The attacks came roughly one month after September incidents targeting South Korean financial institutions. Researchers linked that wave to a suspected China-based hacker using Artex, an AI penetration-testing tool, but investigators have not established the latest breaches’ cause. South Korea’s Financial Services Commission called for stronger cybersecurity and plans checks across dozens of private-sector IT systems after attacks on financial firms and government agencies. Japan disclosed an October 27 incident involving GMO Internet after attacks on its financial institutions, although no connection between the countries’ cases is established. The FSC, Daishin, Mirae and Bithumb did not immediately respond to comment requests.
Positives
- Daishin Securities notified all affected customers and is cooperating with authorities investigating the breach.
- Daishin pledged to compensate customers for resulting losses where required by law.
- Mirae Asset and Bithumb have not confirmed that customer information was taken in their separate incidents.
- South Korea plans security checks across dozens of private-sector IT systems.
- The Financial Services Commission called for stronger cybersecurity across financial firms and government agencies.
Risks & concerns
- Daishin Securities exposed names, email addresses and mobile numbers belonging to 38,490 customers.
- Daishin, Mirae Asset and Bithumb were hit roughly one month after September attacks on South Korean financial institutions.
- Researchers linked September’s attacks to a suspected China-based hacker using the AI penetration-testing tool Artex.
- Investigators have not determined the root cause of the latest South Korean breaches.
- Japan’s October 27 GMO Internet incident adds to a wider Asian attack wave, although no connection has been established.