GMO Internet Group Chairman and CEO Masatoshi Kumagai said the company failed to address a security flaw flagged in 2024 before an August attack exposed customer data and harmed customers' assets, The Straits Times reported.
Kumagai apologized to customers over the attack and its impact on their assets. The group announced a 30% cut to his remuneration for three months, alongside cuts for three other executives.
Specialists at a group company had flagged the vulnerability in April 2024. GMO said it believed extraordinary maintenance had fixed the problem; an executive acknowledged at the Nov. 2 news conference that the company's risk analysis had been insufficient.
An attacker accessed a server on Aug. 5, 2026. GMO learned of the incident on Oct. 20, one day after a customer asked about suspected unauthorized transactions. The company confirmed that a third party had installed unauthorized software in some customer server environments.
The breach involved Onamae.com Desktop Cloud, a service used for foreign-exchange trading. GMO said it had not established how the attacker entered or the full financial impact. The incident also involved a leak of customer information.
GMO Internet had previously said current users would receive ¥5,000 each and that it would cover verified unauthorized trading losses, as EconoTimes outlined in its coverage of the compensation plan.
