We have received a report from BIGLOBE Corporation (hereinafter referred to as BIGLOBE) that there is a possibility that customer email-related information may have been leaked due to unauthorized external access to "BIGLOBE Mail," which is used by customers who have contracted for "EDION Hikari Plus" and "EDION SIM." We sincerely apologize for the great inconvenience and concern this has caused to our customers using the affected services.
 

1. Circumstances of the Incident
"BIGLOBE Mail" utilizes the email system (hereinafter referred to as "this system") provided by KDDI Corporation (hereinafter referred to as "KDDI") to ISPs. It has come to light that customer information may have been leaked due to unauthorized access resulting from the exploitation of a vulnerability in third-party software used by this system.
BIGLOBE has reported that KDDI modified the system on June 17, 2026, and implemented technical protection measures to prevent further damage. We are continuing our investigation to identify the extent of the impact.
Please refer to KDDI's announcement for further details.
https://newsroom.kddi.com/news/assets/2026/kddi_nr_s-71_4593/kddi_nr_s-71_4593_pdf_01.pdf

2. Number of customers whose information may have been leaked
Currently under investigation

3. Information that may have been leaked
BIGLOBE email address, BIGLOBE ID, and password
We are continuing to investigate the extent of other impacts.

4. Information for Affected Customers
Although we have implemented technical security measures, there is a possibility that your BIGLOBE email address, BIGLOBE ID, and password may have been illegally obtained by a third party as a result of this incident. As a necessary measure to ensure the protection of your data and thoroughly eliminate potential risks, we are advising you to change your password as soon as possible.

■BIGLOBE Member Support Page
Apology regarding unauthorized access and request to change your password.
https://support.biglobe.ne.jp/news/news796.html

If you have any questions, please contact our customer support center below.

■個人のお客様
BIGLOBEお客様相談 特設窓口　0120-69-6068
年中無休9時～18時[通話料無料]

That's all