Cyberattacks in Japan exposed data of tens of millions of users
Several major Japanese companies reported breaches this week; government is investigating possible links and urging security measures.
Multiple Japanese companies reported cyber intrusions this week that may have exposed the personal data of tens of millions of users, prompting a national probe into whether the incidents are linked.
Among the firms that disclosed incidents are Daiwa Securities, GMO Research, Rakuten Drive, the Nikkei media group and the Yakiniku King restaurant chain, officials said this week.
Park24 announced that the breach affected 6.6 million customer accounts. GMO Research said its survey service incident could involve nearly 950,000 users, while Monogatari — owner of the Yakiniku King chain — reported that data from about 10 million customer accounts were accessed without authorization.
Government response and consumer advice
Chief Cabinet Secretary Minoru Kihara said authorities do not yet know whether the intrusions are connected and that investigators are working to map the full scale of the damage.
"We are working to determine the full extent of the damage, analyzing the methods and trends of the attacks," Kihara said. The government has urged citizens not to reuse passwords across services, to enable multi-factor authentication and to exercise caution when opening links.
Investigations are ongoing as companies continue to assess what specific information was exposed and notify affected users.
Photo: press material from the event
