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JAENES
SSLeak confirmedNovember 3, 2026 announced

アソビューData breach / unauthorized access incident

笹尾 祐太朗の写真Reviewed by Yutaro SasaoWritten by Leak Watch editorial team published ・ updated
Occurred on
October 28, 2026
Announced on
November 3, 2026
Severity
SSLarge-scale compromise of sensitive data such as payment or identity-verification records affecting millions.
Scale
15,821,184 records
Main impact
Unauthorized access to the vendor's email delivery service resulted in the leakage of approximately 15,821,184 members' records, including names, dates of birth, email addresses, and purchase and usage histories. Identification of the affected members is not yet complete, and no misuse has been confirmed to date.
Information involved
Email addressUser / member IDFull nameDate of birthPhone numberHome address
Cause / key point
Leak due to unauthorized access caused by a vulnerability in the vendor service's web server and problems in the system environment.About Exploitation of vulnerabilities
Industry
Services & other
Listing / capital
Unlisted
Sources
Last updated
November 4, 2026

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Written & reviewed

笹尾 祐太朗の写真

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: Exploitation of vulnerabilities(Breaking in through holes in software and devices)

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