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JAENES
SPossible leakOctober 6, 2026 announced

楽天会員データ販売主張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
Unconfirmed
Announced on
October 6, 2026
Severity
SCompromise of deep personal data or usable credentials.
Scale
1,000,000 records
Main impact
A third party claims to be selling member data including names and addresses totaling 約1億100万件, but the authenticity, count, and source are unverified and no leak has been confirmed.
Information involved
Home addressFull name
Cause / key point
Cause is under investigation.
Industry
IT & telecom
Listing / capital
Unlisted
Sources
Last updated
October 20, 2026
Home addressFull nameHow severity is assessed →

Is this incident worth paying attention to?

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: Under investigation / not stated(Cause not disclosed)

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