Atmeltomo 2021 Data Breach
The 2021 Atmeltomo data breach is a credential incident affecting a Japan-based email friend-search and community site.
Exposed Data Types
4- Email addresses
- IP addresses
- Hashed passwords
- Usernames
About This Breach
Within an approximately 1.3-million-raw-row context, the external source reports 580,177 unique emails and local search contains 579,860 records, a difference of 317.
The four classes are emails, IPs, unsalted MD5 password hashes, and usernames. Raw rows, unique emails, people, friendships, active accounts, and local records are not equivalent measures. Unsalted MD5 is not plaintext but is weak by current standards.
Names, phones, physical addresses, payments, government IDs, and private messages are not classes. A record does not establish identity, Atmeltomo membership or a friendship or social relationship, IP or location, username or password ownership, field co-occurrence, account takeover, or misuse.
If the old password genuinely belonged to the person and was reused elsewhere, it should be replaced. Friendship or community associations must remain private, and fake introduction or account messages should be verified independently.
Verification and editorial method
LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.
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