Japan has recently experienced a series of large-scale cyber attacks. According to the latest statistics from the Personal Information Protection Commission, the total number of personal information leaked by companies due to illegal intrusions has reached approximately 260 million since April this year, and the number of cases increased sharply in October. After GMO, a large online services group, was blackmailed by hackers, companies such as Muji, All Nippon Airways (ANA), and Japan Airlines (JAL) have successively reported risks of personal information leakage, and even the Japanese Ministry of Foreign Affairs was illegally hacked. Chief Cabinet Secretary Minoru Kihara said today that the government takes the situation "extremely seriously" and will propose emergency information security countermeasures next week and expand the use of U.S. high-performance artificial intelligence (AI) technology to strengthen defense.
The Yomiuri Shimbun and Nikkei Shimbun reported that Japan’s Personal Information Protection Commission announced on the 29th that from April to October 16 this year, a total of 2,094 cases of illegal intrusion and personal information leakage were reported by companies, exceeding the 1,256 cases in 2025. Among them, there were 830 cases in the first half of October, 2.7 times the 303 cases in the whole month of September, and there were 22 large-scale cases involving more than 1 million people.
Comprehensive Japanese media reports, MUJI operating company Ryohin Project announced today that the official application "MUJI APP" has been illegally hacked, and up to about 27.26 million pieces of customer information may have been leaked, including email addresses, dates of birth and gender, but not including credit card information, names and addresses. Cosmetics company DHC announced on the 30th that its online store had been illegally invaded, resulting in the membership information of 5,096 accounts being tampered with by a third party.
The aviation industry has also suffered one after another. ANA announced today that due to the illegal intrusion of the Spanish Amadeus passenger service system entrusted to it, the booking information of approximately 37,800 passengers has left traces of being viewed by a third party. About 1,700 of them may have had passport numbers and contact information. Japan Airlines and Japan Air Transat also reported that the reservation information of about 92,000 passengers was affected.
Japan's Ministry of Foreign Affairs confirmed today that the network system used for external communications was illegally invaded. About 3,600 pieces of personal information, including names and email addresses, may have been leaked, of which about 900 involved outsiders.
Minoru Kihara pointed out at a press conference today that about 260 million people's personal information has been leaked and the rapid increase in large-scale cases, the government "takes it extremely seriously" and will make every effort to eliminate the uneasiness of the people and companies.
The Japanese government today established a "Special Website for Cyber Attack Response" on the National Cyber Security Office (NCO) website to integrate the consultation windows and information security warnings of various ministries. Various government ministries have joined forces with specialized information security agencies to conduct comprehensive traceback and patching of vulnerabilities in the Ministry of Foreign Affairs and the Joint Government System (GSS) of the Digital Agency that were damaged recently. Kihara also said that emergency countermeasures will be compiled next week, including strengthening support for victim companies and using "access harmless measures" in accordance with the law to prevent the attack from continuing to expand.
Nikkei reported today that the Japanese government has asked U.S. artificial intelligence development companies to expand the provision of high-performance AI models to check security vulnerabilities in the government and important infrastructure, and will include relevant cooperation in a cybersecurity countermeasure plan scheduled to be announced next week.
The government will prioritize the inspection of important information systems involving personal data and national security, and compare the vulnerability detection capabilities of different AI models to further strengthen defense measures. In the future, relevant results will also be extended to important infrastructure companies such as electricity, gas, and communications.
On the 26th, Takaichi Sanae instructed relevant ministries to strengthen cooperation with overseas institutions to trace the source of attacks and improve system vulnerabilities. The Japanese government believes that some recent attacks are suspected of using high-performance AI technology, and will use AI to strengthen defense capabilities in the future, and requires companies to speed up patching vulnerabilities, update software, and introduce multi-factor authentication.
