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JAENES
SSLeak confirmedNovember 7, 2026 announced

株式会社シグナルトーク（Maru-Jan）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
November 4, 2026
Announced on
November 7, 2026
Severity
SSLarge-scale compromise of sensitive data such as payment or identity-verification records affecting millions.
Scale
1,855,578 people
Main impact
Email addresses and passwords of 185万5,578 members were downloaded externally, resulting in a large-scale credential leak.
Information involved
Email addressPassword
Cause / key point
Data exfiltration via unauthorized access that exploited a management system function.About Abuse of credentials
Compensation & remedies
Announced it will provide 3,000 points (3,000 yen) per member.
Industry
Services & other
Listing / capital
Unlisted
Sources
Last updated
November 9, 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: Abuse of credentials(Logging in legitimately with leaked or guessed passwords)

Read the Abuse of credentials guide and national trends →

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