Confirmed

Komatsu: misconfigured user directory let 139,302 registered users see each other’s data

A user-management misconfiguration allowed registered users to view each other’s directory data inside the system; discovered Apr 23, 2026 and disclosed June 16. Not exposed to the open internet.

Last updated: 2026-11-09

Overview

139,302 users (name, email, user type, some access timestamps).

Timeline

  1. Occurred
  2. Discovered
  3. Disclosed

Organization response

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

What you can do

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.

Sources

  1. 個人情報が閲覧可能な状態にあったことに関するお知らせ株式会社小松製作所 · 2026-11-09

Related information

Share a report

No published information yet

Information appears here after source checks or moderation.

Comments and replies

Write a comment

No account needed. Comments appear immediately.

Do not post private names, addresses, passwords, or codes. Automatic masking is limited; review your content before submitting.

Required fields are marked *.

After submitting the text, you can redact and attach images.

Loading the security check. You can submit once it is complete.