In April 2021, "Japan's largest e-mail friend search site" Atmeltomo suffered a data breach that was later sold on a popular hacking forum. The breach exposed 1.3M records with 580k unique email addresses along with usernames, IP addresses and unsalted MD5 password hashes.
Quick answer — was Atmeltomo breached?
Yes. Atmeltomo was breached in April 2021, exposing 580,177 records including email addresses, ip addresses, passwords. This breach has been independently verified. If your email was involved, your data may still be at risk today. Check if you were affected.
In April 2021, "Japan's largest e-mail friend search site" Atmeltomo suffered a data breach that was later sold on a popular hacking forum. The breach exposed 1.3M records with 580k unique email addresses along with usernames, IP addresses and unsalted MD5 password hashes.
The exposed data included 4 types of personal information. Because passwords were exposed, users who reused their password on other sites are at particular risk. Learn more about what a data breach means for you.
The Atmeltomo breach exposed 580,177 records.
Because passwords were exposed, attackers can use credential stuffing to automatically test your Atmeltomo credentials against hundreds of other websites. Read more about what happens to your data after a breach.
Don't wait to find out — check if your email was exposed in this breach.
Email addresses — used for phishing attacks and credential stuffing against your other accounts
IP addresses — combined with other data, used for identity theft and physical fraud
Passwords — can be used to access your accounts directly or cracked to reveal your actual password
Usernames — used to build profiles and target you with personalised scams
Yes. Stolen data from the Atmeltomo breach remains dangerous years after the incident. Attackers routinely compile data from multiple breaches to build complete profiles, and credentials from 2021 are still actively used in automated attacks today.
Personal information like email addresses, phone numbers, and dates of birth does not expire. Even if you changed your Atmeltomo password, the other exposed data can be combined with information from other breaches to target you. Learn how long stolen data stays dangerous.
Change your Atmeltomo password immediately
Log into Atmeltomo and change your password to something strong and unique — one you have never used anywhere else.
Change any account sharing that password
If you reused this password elsewhere, change it on every affected account. Attackers test stolen credentials against hundreds of popular sites within hours.
Enable two-factor authentication
Turn on 2FA on Atmeltomo and every important account. Even if your password is known, attackers cannot access the account without the second factor.
Check your other accounts for this breach
Run a full email scan to see every breach your address appears in — not just this one.
Check all my breaches — freeBreach pages are built from structured breach records and reviewed for practical risk guidance by EmailLeaked. Risk labels reflect exposed data types and are intended to help readers prioritise action.
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