NTT Docomo has announced that due to unauthorized access to My docomo on Wednesday, November 4th, user information for up to 294,839 accounts (204,157 individual users, 90,682 corporate users) may have been leaked.
The leaked information for all affected users includes five categories: "Name, date of birth, age, etc.," "Address, contact phone number, email address, etc.," "Identification document number," "Contract information such as mobile phone number and contract date," and "Contract details such as rate plans, options, and discounts."
Furthermore, for some users, the leaked data also includes "Names and contact information of legal representatives and procedural agents," "Company/corporate name, location, etc.," "Financial institution name, account number, etc.," and "Information related to the Child-Rearing Support Program."
Regarding the unauthorized access incident, after detecting alerts for a large volume of access, My docomo was put into maintenance mode. Although the attack route was blocked and service was temporarily restored, the possibility of unauthorized access was detected again. My docomo was then put back into maintenance mode, and the user information leak was confirmed.
For individual users whose information may have been leaked, SMS messages were reportedly sent today, Friday the 6th. Additional notifications are also planned via direct mail and other methods.
Docomo is urging users to follow the requests below and plans to offer a consolation payment in the future (details to be announced separately).
Do not access URLs contained in suspicious emails or SMS messages. Do not open suspicious attachments. Do not enter or provide passwords, PINs, credit card information, etc. Even if the sender seems to know your information, do not easily trust them. If you find anything suspicious, please contact us immediately. * If you notice any unfamiliar logins, purchases, or contracts, please contact us immediately.
