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So-net and plala breach: ETCISO reports Sony disclosed 2.58 million records

ETCISO reports Sony disclosed a breach of So-net and plala customer records, so affected users should change reused passwords and watch for phishing.

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No CVE or vulnerability is named; ETCISO reports Sony says an unauthorized party gained access to its systems on October 19, 2026

What happened

ETCISO reports that Sony has disclosed a data breach affecting customers of So-net and plala, two Japanese internet service providers owned by Sony Network Communication ETCISO. According to ETCISO, Sony says an unauthorized party gained access to its systems on October 19, 2026, and 2,585,481 customer records were affected. ETCISO says the data was “reportedly leaked” on October 24 and that Sony disclosed the incident on October 27.

According to ETCISO, the records break down as follows:

  • So-net: 2,141,986 records
  • plala: 443,495 records
  • 54,401 email and password combinations identified within the exposed data
  • 16 bank account records, including account numbers

ETCISO reports the exposed data includes names, user IDs, dates of birth, phone numbers, email addresses and other customer information. According to ETCISO, Sony says its investigation found no sign that credit card numbers or expiration dates were taken, and that bank PINs are not stored in its systems. Sony also says the breach does not touch PlayStation Network accounts, per ETCISO.

ETCISO reports Sony says it shut down the affected servers, blocked the unauthorized access, reset passwords for the impacted email accounts on October 27 and reported the incident to Japan’s Personal Information Protection Commission. The investigation is ongoing, so ETCISO notes the numbers could change.

What is not confirmed: this advisory relies on a single news report. No Sony statement or regulator notice is among the sources, and there is no independent verification. The entry point, who was responsible and where the data was leaked are not confirmed.

Am I affected?

  • So-net or plala customers in Japan: possibly. ETCISO reports these are the affected services ETCISO.
  • PlayStation Network users: not affected, according to Sony as reported by ETCISO.
  • Whether a specific account is in the exposed set is not confirmed in the source.

What to do now

  1. If you reused your So-net or plala password on any other service, change it there. ETCISO notes the 54,401 email and password pairs could be tried on other sites ETCISO.
  2. Follow Sony’s advice, as reported by ETCISO: do not click suspicious links. Be wary of emails or texts that use your name or phone number.
  3. Use a unique password for each service, for example through a password manager. ETCISO suggests this.
  4. If you believe your bank account details were among the 16 exposed records, contact your bank and monitor your account, as ETCISO recommends.

Sources