KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords: What Was Exposed & What To Do
The KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords (reported July 8, 2026) exposed email addresses and passwords belonging to roughly 12.2M people. If you have an account with them, your information may now be circulating on the open web and with data brokers. Here’s exactly what happened, how to check if you were affected, and what to do next.
What was exposed
- email addresses
- passwords
How to check if you were affected
Run a free exposure scan with your email address. It matches you against known breach datasets and shows where your information has surfaced. Check if you’re exposed →
What to do if you were in the KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords
- Change the password on that account — and anywhere you reused it — then turn on two-factor authentication (2FA).
- Expect targeted phishing that references this breach — be skeptical of unexpected emails asking you to log in, verify, or pay.
- Your physical address may be circulating — remove yourself from data-broker and people-search sites to lower your doxxing risk.
- Remove your personal information from data-broker sites so the leaked data can’t be combined against you — GalaxyWarden files those removals for you.
How this breach connects
Frequently asked questions
Was my data in the KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords breach?
The fastest way to know is a free exposure scan — it checks your email address against known breach data, including recent incidents like this one.
What information was exposed in the KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords?
The reported exposed data includes: email addresses, passwords.
What should I do after the KDDI Discloses Breach Impacting 12M+ Customer Emails and Passwords breach?
Change your password for that account and anywhere you reused it, turn on two-factor authentication, and remove your personal information from data-broker sites so it can’t be combined with the leaked data.
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