Japanese companies have faced a growing wave of cyberattacks in recent weeks, exposing millions of customers’ records as analysts warn that artificial intelligence is helping hackers exploit long-standing security weaknesses and overcome language barriers that once offered some protection.
More than 500 breaches of corporate systems were reported in the year to this month, surpassing the total for all of 2025, the Yomiuri newspaper reported last week.
On October 7, a ransomware attack on IDC Frontier – a Japanese cloud hosting and data centre services provider – paralysed systems used by 495 companies and local authorities in the country.
Those affected included railway operator JR East, which confirmed that more than 6 million customer accounts had been compromised. Used book retailer BookOff also reported that data belonging to 6.43 million members had leaked.