Security NEXT reported a data breach at Istyle (Japan) on 4 November 2026. It affected 3,000,000 users.
What we know as of
Status
Reported by Security NEXT; not yet confirmed by Istyle or an authority.
People affected
3,000,000 users.
What was exposed
Email addresses, Phone numbers, Dates of birth, Names, Addresses, Gender, User IDs and Nicknames.
When
First reported 4 November 2026.
How
Hacking, through Yumilink.
Istyle’s record
No earlier breach on record under this name.
Not known yet: when it began and who was behind it. This page is updated as notices and statements come in.
Every fact above has its source below. Journalists: free to quote with credit (“Privacy Unpacked data breach tracker”, with a link to this page and the date); the figures can move. Follow this breach (feed) · Every major breach · Ask us for a figure
People affected
3,000,000users
Reported
4 November 2026News report
What was exposed 8
Email addresses
Phone numbers
Dates of birth
Names
Addresses
Gender
User IDs
Nicknames
How it happened
How
Hacking The cosmetics review information site "@cosme" has been subjected to a cyberattacksourceOur translation from Japanese化粧品の口コミ情報サイト「＠cosme」がサイバー攻撃を受け
Way in
Yumilink Some email delivery uses Yumir Link's "Cuenote FC", and signs of breach have been detected in that environmentsourceOur translation from Japanese一部メールの配信にユミルリンクの「Cuenote FC」を利用しており、同環境において侵害の形跡が検知された
News reports are read by an AI model; every fact taken from an article was checked word for word against it, and anything it could not find was dropped. · Corrections and changes
Questions about the Istyle breach
Was Istyle hacked?
Security NEXT reported a data breach at Istyle (Japan) on 4 November 2026. It affected 3,000,000 users. How it happened, by the sources: hacking, through Yumilink. It has been reported but not confirmed by Istyle or an authority.
What data was exposed in the Istyle breach?
Email addresses, Phone numbers, Dates of birth, Names, Addresses, Gender, User IDs and Nicknames, by the notices and reports on this page.
How do I know if I was affected?
Organisations normally tell the people whose data was involved, by letter or email, and that notice says what of yours was in it. We cannot look up individual people. If you got a notice, check that it is real, then follow the steps on this page.
Is there a Istyle data breach settlement?
No settlement open for claims is on record for Istyle as of 15 November 2026. Every open settlement is listed with its deadline.
Is a letter, email or text about the Istyle breach real or a scam?
A real notice names the breach, says what data was involved and never asks for a password, a code or a payment. Criminals often send fake notices after a breach is in the news. Do not use links or phone numbers in the message: go to Istyle’s own site, or check the letter here.
Privacy Unpacked