调查中

Yamagata City: staff and resident data may have leaked via contractor YCC ransomware

Possible data leak: After the April 2, 2026 YCC attack, a review through April 15 found city data including ended contracts still on the vendor server; disclosed April 16.

最后更新: 2026-11-09

此内容以 English 显示。

概述

Per-system counts (HR/payroll 6,167; health 31,766; child consultation 2,185) are not summed (count blank). Includes My Number and health-check fields.

时间线

未知发生
2026-04-02发现
2026-04-16披露

组织应对措施

Per the notice, the organisation investigated and contained the incident, notified individuals and offered monitoring or protective resources.

用户应对建议

Be wary of emails, SMS or calls impersonating the organisation; do not open links or attachments or enter passwords or card details. Change reused passwords on other services.

信息来源

株式会社YCC情報システムに対するサイバー攻撃に係る山形市保有個人情報の漏えいのおそれがある事案について山形市 · 2026-11-09