# Sony's ISP So-net Suffers Massive Data Breach Affecting Millions

*Published October 30, 2026*
*Source: [https://www.securityweek.com/hackers-steal-2-6-million-records-from-sonys-japanese-isp-so-net/](https://www.securityweek.com/hackers-steal-2-6-million-records-from-sonys-japanese-isp-so-net/)*

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## Article

Sony Network Communications revealed that hackers have compromised the personal information of millions of current and former subscribers to its Japanese internet services, So-net and Plala. The attack, which took place on October 19, resulted in the exposure of nearly 2.6 million records. The breach was discovered by the company on October 23, prompting immediate action to secure the affected server and block malicious traffic. 

The compromised data includes sensitive details such as names, dates of birth, gender, phone numbers, email addresses, and user IDs. Notably, 2.14 million records belong to So-net subscribers, while 443,000 are linked to Plala subscribers. Among these, approximately 293,000 records pertain to individuals who had canceled their subscriptions since March 2026. The hackers also accessed email addresses and passwords for around 54,000 accounts across four email services, excluding the basic mailbox provided with subscriptions. 

In response, So-net has initiated a mandatory password reset for affected accounts to mitigate unauthorized access to email services. Additionally, 16 records containing bank account information were part of the breach, though no credit card data was compromised as So-net does not store such information. The exact method of the breach remains under investigation, with the incident reported to Japan's Personal Information Protection Commission. So-net continues to assess the situation to prevent future occurrences.