Japanese teen allegedly uses AI-generated program to breach internet cafe operator
A 17-year-old boy in Osaka was served an arrest warrant on suspicion of breaching Kaikatsu Frontier's server using a program generated by conversational AI, reportedly sending unauthorized commands to export personal data. The attack in January 2025 resulted in the potential leakage of personal information for 7.3 million customers, though no actual data misuse has been confirmed.
What happened
On 18 January 2025 in the evening, Kaikatsu Frontier Inc. detected an unauthorized access to its server and immediately disconnected the network.
A 17-year-old high school student in Osaka is suspected of sending unauthorized commands to Kaikatsu Frontier's server approximately 7.24 million times using a program generated by conversational artificial intelligence to export personal data.
The student allegedly concealed his true intention when prompting the AI to generate the program.
Reported impact
The personal information of 7,290,087 customers was at risk of leakage, including names, addresses, phone numbers, birthdates, member numbers, points, and store codes, affecting Kaikatsu Club members, temporary members, and FiT24 gym members.
The attack obstructed the business operations of Kaikatsu Frontier Inc.
Index analysis
Although conversational AI services generally do not generate content for crimes, the student reportedly concealed his true intention when prompting the AI.
Governance controls
Kaikatsu Frontier implemented security measures including modification of the vulnerable program, deployment of new security software, application of security patches, and strengthened monitoring and blocking of unauthorized access attempts.
The company reported the incident to police and the Personal Information Protection Commission and notified affected customers by email or post between 29 January and 13 March 2025.
Classification
Sources and evidence
Sources not yet published
This record was researched and written by the Index from original reporting. Its sources are still being verified by an editor, and they are listed here once that check is complete. Until then the record carries no reviewer.