SignalTalk security incident history
Hacking, data breaches and other security incidents involving SignalTalk, with related coverage.
Incidents: 1 · Most recent
Maru-Jan leak exposes emails and passwords of all 1,855,578 members
1.9MImpact: Passwords and registered email addresses of all 1,855,578 members leaked
The passwords and registered email addresses of all 1,855,578 members of Maru-Jan, an online mahjong service operated by Japan’s SignalTalk, were downloaded externally. The attacker exploited a function in the administration system. After emergency maintenance and blocking the intrusion route, the operator resumed the service on November 7, 2026, and asked members to change their passwords.
Related reports: 12 · last report →