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high severity April 16, 2021 · 1 min read

Atmeltomo Data Breach (2021)

If you are a customer of Atmeltomo, here’s what’s now in circulation.

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.

Atmeltomo Data Breach (2021)

What the free scan actually returns

Sample resultyou@email.comIllustrative — not a real person

Found on people-search siteswe remove these

These listings are live, public, and legal to remove — and removing them is what we do.

value redacted in this sampleage, relatives, address historySpokeo
value redacted in this samplephone, household, property recordsBeenVerified
value redacted in this sample582 companies checked

Found in breach recordsverifiedreported — unverified

Each record is labeled: confirmed breach data, or an attacker’s claim no one has verified.

verifiedvalue redacted in this samplepassword + phone · 2024telecom breach
unverifiedvalue redacted in this sampleclaimed in ransomware listing · 2026leak-site claim

Leaked data cannot be deleted from the internet — anyone claiming otherwise is lying. Broker listings can be removed. We do the second, and show you exactly what to fix from the first.

Were you a Atmeltomo customer?
Atmeltomo is one listing. Your email is probably in others.
580K accounts were exposed here. Check whether yours is one — and find every other leak tied to the same address, in about 15 seconds. No account, no card.

By running your scan you agree to the Terms and Conditions and the Privacy Policy, and to GalaxyWarden emailing you the results of this scan.

Report details & sourcing

Severity High contact details only, none of them permanent
Disclosed April 16, 2021
Last reviewed July 22, 2026
Affected 580K
Data exposed Email addressesIP addressesPasswordsUsernames
By GalaxyWarden Threat Research · Editorial & sourcing standards
Editorial & sourcing policy
GalaxyWarden is a breach-monitoring service and news aggregator. We do not exfiltrate, host, purchase, or redistribute stolen data. Breach information is compiled from publicly accessible sources and threat-intelligence platforms, and is reported as claims attributed to their source. We promptly correct or remove material shown to be inaccurate — see our content & takedown policy or write to support@galaxywarden.com.
Sources: Have I Been Pwned
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