What happened
- Financial institutions in South Korea suffered a new wave of cyberattacks, TechCrunch reported on October 28, 2026. Those affected are the brokerages Daishin Securities and Mirae Asset Global Investments, plus the crypto exchange Bithumb.
- According to local media cited by TechCrunch, Daishin reported an attack that exposed the names, email addresses and mobile numbers of 38,490 people who trade with the firm.
- Daishin notified those affected, is cooperating with authorities and will compensate losses as required by law.
- Mirae and Bithumb reported separate incidents on Wednesday the 28th, but neither confirmed that user data was taken.
Why it matters
- It is the second wave in about a month against the South Korean financial sector. This time it reaches brokerages and a crypto market, which, according to TechCrunch, widens concern beyond the banking system.
- The financial regulator called for stronger security measures after the string of attacks on financial firms and government bodies, according to officials in Seoul.
- The country plans to review the security of dozens of private-sector IT systems, a response that goes beyond the affected firms.
- For people with accounts at those firms, the immediate risk is targeted fraud: with a name, email and phone number, an attacker can craft convincing impersonation messages.
The number
38,490 people. That is the number of Daishin Securities users whose personal data was exposed, according to South Korean media cited by TechCrunch.
Context
Security researchers linked the September wave to an attacker suspected of operating from China who used an automated penetration-testing tool called Artex. For this week’s attacks, authorities are still investigating the cause and have not attributed them.
The region is going through a similar streak. Japan reported a cybersecurity incident at GMO Internet on Tuesday, after a series of attacks on its financial institutions. TechCrunch attributes the run of incidents in Asia to years of weak defenses, although investigators have not established a link between the Korean and Japanese cases.
Bithumb’s case carries particular weight. Crypto exchanges hold assets that can be transferred irreversibly, so unauthorized access can turn into direct losses and not only a data leak.
What’s next
- It remains to be seen whether Mirae and Bithumb will confirm theft of data or funds when their reviews end.
- The private-sector systems audit announced by the South Korean government will define what standards financial firms must meet.
Bottom line
Attacks on sensitive data keep recurring in other sectors: Quest Diagnostics confirmed an attacker accessed patient records and ransomware operators exploit a GlobalProtect flaw that bypasses MFA. In trust infrastructure, browsers blocked eight eMudhra certificates, and on offensive tools, see the global race for models that write exploits.
Sources
- TechCrunch — South Korea’s financial industry hit by fresh wave of cyberattacks (October 28, 2026). The statements by Daishin, Mirae and Bithumb could not be consulted; the figures come from TechCrunch, which cites South Korean media.
- Cover image: AnbyG, CC BY-SA 4.0, via Wikimedia Commons
Edited by Rodrigo Cornejo. How we select and verify: who writes these notes.
