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3 clusters · 16 sources · 7 days · First seen · Last updated

Arcadia disaster information system data breach

Overview

A major cybersecurity breach involving the IT company Arcadia has compromised the SpeeCAN RAIDEN disaster information distribution system in Japan. The unauthorized access targeted a system used by approximately 800 local governments to disseminate emergency alerts and weather warnings.

Arcadia reported that the breach could affect up to 3,136,000 email addresses and 105,000 phone numbers. Affected municipalities include Kyoto, Aomori, Akita, and Wakayama. Specific reports indicated potential leaks of resident emails, staff details, and even facial photographs in certain cities.

By mid-October, disaster prevention systems in regions including Toyama and Akita prefectures began resuming operations. In Toyama, Takaoka City restored multilingual and fax-based email services on October 15, noting that approximately 4,700 names, emails, and phone numbers may have been leaked. Similarly, Yokote City, Kazuno City, and Kosaka Town in Akita Prefecture resumed distributions, with Yokote City reporting instances of suspicious emails during the downtime.

The scope of the breach has expanded to include law enforcement. Approximately 125,000 police officers and staff across 20 prefectural police departments—including Kanagawa, Hyogo, Saitama, and Aichi—have potentially had their personal information exposed. Leaked data reportedly includes names, affiliations, email addresses, and private mobile numbers used for emergencies. Additionally, the breach impacted roughly 16,000 private citizens and 2,600 corporations registered for crime prevention services in Kyoto, Shimane, Yamaguchi, and Fukuoka. The National Police Agency is investigating the incident alongside Arcadia.

Entities

Arcadia · Saitama Prefectural Police · Saga City · Takaoka · Yokote

Claims

What the coverage asserts, and how many sources carry each claim.

Timeline

  1. [CRIME] 7 sources
    Arcadia data breach affects 20 prefectural police forces in Japan

    An unauthorized access at IT firm Arcadia has potentially leaked personal data of 125,000 police officers across 20 Japanese prefectures and 16,000 citizens.

  2. [TECHNOLOGY] 4 sources
    Disaster prevention systems resume service after Arcadia unauthorized access

    Disaster prevention email services in several Japanese municipalities, including Takaoka and Yokote, have resumed following a service disruption caused by unauthorized access to the provider Arcadia.

  3. [TECHNOLOGY] 10 sources
    Arcadia disaster information system breach causes widespread data leaks in Japan

    A cyberattack on Arcadia's disaster information system has caused massive potential data leaks across hundreds of Japanese municipalities, affecting millions of email addresses and phone numbers.

Sources

aba-net.com · classics.itmedia.co.jp · cybersecurity-jp.com · fm791.net · fnn.jp · hokkoku.co.jp · ikki.wajcp.net · kyoto-np.co.jp · news.cube-soft.jp · nishinippon.co.jp · piyolog.hatenadiary.jp · sakigake.jp · taichimaster.jp · wakayamashimpo.co.jp · www2.city.kyoto.lg.jp · yomotto.jp

This summary has been updated 1 time: see revision history