アララ（アララメッセージ）Data breach / unauthorized access incident
- Occurred on
- October 28, 2026
- Announced on
- October 28, 2026
- Severity
- CLimited data such as email addresses and identifiers.
- Scale
- 3,010,000 records
- Main impact
- Approximately 約301万件 email addresses registered in the end-user list were exfiltrated from the mail delivery service's server. Addresses registered as recipients by client companies were leaked, creating a risk of secondary harm such as phishing.
- Information involved
- Email address
- Cause / key point
- Unauthorized access caused by a third party exploiting a vulnerability in the web server.About Targeted email & phishing
- Industry
- IT & telecom
- Listing / capital
- UnlistedParent company: ペイクラウドホールディングス
- Sources
- Last updated
- October 30, 2026
Where to go for this information
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Written & reviewed
Reviewed byYutaro SasaoFounder & CEO, MediaLeap Inc.
CEO of MediaLeap Inc. Working on both sides of web advertising and web media since 2013; founded the company in May 2025.
Review scope: cross-checking against primary sources (official and government announcements), verifying claims stay within the facts, and checking source attribution。Last reviewed:
Written by:Leak Watch editorial team (AI-assisted drafts verified against sources by the editorial team) · Reviewer profile · Request a correction
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Attack method classification: Targeted email & phishing(Fake emails and sites that steal credentials)
Read the Targeted email & phishing guide and national trends →