Bithumb Confirms Employee Data Leak, Says Crypto Wallets Are Safe

Highlights:

• South Korean crypto exchange Bithumb reported an employee data breach, but said customer crypto wallets remained safe.
• Daishin Securities reported a data leak affecting 38,490 customers, while Mirae Asset also faced suspicious access.
• South Korean regulators launched security checks at affected firms and called for stronger protection against cyberattacks.

South Korean cryptocurrency exchange Bithumb has reported a data breach after an unauthorized party accessed an internal employee system. The incident comes alongside cyberattacks affecting Daishin Securities and Mirae Asset Global Investments. Financial regulators have launched on-site checks to investigate the security incidents across the country’s financial sector.

According to an October 28 Yonhap News Agency report, Bithumb discovered unusual outside access to its mobile workplace system on October 27. The exchange is still examining what information was exposed and whether customer records were affected.

South Korea’s Second-Largest Crypto Exchange Bithumb Confirms Security Breach

According to Yonhap News Agency, South Korea’s second-largest cryptocurrency exchange, Bithumb, confirmed that an unauthorized external party accessed its internal mobile groupware system, resulting in… pic.twitter.com/aMf5l2rVIZ

— Wu Blockchain (@WuBlockchain) October 28, 2026

Bithumb Says Crypto Wallet Information Was Not Leaked

The information confirmed as leaked so far relates to Bithumb employees. The company has not confirmed that customer information was stolen. It has also not provided a final figure for the number of people affected.

Later on October 28, Bithumb told regulators that the attack targeted a system used to support staff. It said information that could help with unauthorized payments or crypto transfers, including cryptocurrency wallet addresses, had not been leaked.

The Financial Services Commission (FSC) met with Bithumb, the Financial Supervisory Service (FSS), the Financial Security Institute and the Digital Asset Exchange Alliance (DAXA) to review the incident. DAXA represents South Korea’s major cryptocurrency exchanges. Regulators plan to examine how the breach happened and oversee measures to protect users if they identify any damage. Investigators have not reported any cryptocurrency theft linked to the Bithumb incident.

Daishin Securities Reports 38,490 Customers Affected

The cyberattacks also affected financial firms outside the crypto industry. Daishin Securities confirmed that hackers exposed the personal and credit information of 38,490 customers. The brokerage detected unauthorized access to a server used for opening investment accounts on October 17. It reported the incident to regulators and later confirmed the data leak after an internal investigation.

Meanwhile, Mirae Asset Global Investments detected suspicious activity from an external internet address on some of its web systems. The company quickly blocked the access and launched an emergency response. Mirae Asset said the incident affected its internal business systems but did not expose sensitive personal details, credit information or investor data. The company continues to investigate the cause and full extent of the incident.

South Korean Regulators Increase Security Checks

The FSS has sent inspection teams to Bithumb and Daishin Securities. If the reviews uncover legal violations, regulators may begin formal inspections. FSS Governor Lee Chan-jin also urged financial companies to strengthen their cybersecurity controls. Speaking to the chairpersons of eight banking groups, he warned that artificial intelligence could help attackers find weaknesses and launch several attacks at once.

The latest cases follow a separate security incident involving Mirae Asset Life Insurance on October 26. They add to concerns about attacks targeting banks, insurers, crypto exchanges and investment companies in South Korea. The FSC plans to hold another meeting next week with financial regulators, industry groups and major banks to review their response to AI-related hacking threats.

The commission also wants cryptocurrency firms to adopt stronger security standards similar to those used by traditional financial institutions. It plans to examine better safeguards for virtual asset businesses that do not fall under the same electronic financial transaction rules as conventional financial firms.