---
title: NIFTY: intruders reached an internal fiber-line application management tool; up to 542,513 @nifty Hikari customers' IDs, names, birth dates, addresses, phones and emails may be exposed | ctxsec
url: https://ctxsec.com/items/nifty-line-application-system-542k
description: ""
status: "confirmed (NIFTY first report, Oct 19); leaked fields still under investigation"
published: 2026-10-20
---

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[← Cybersecurity News](/news) · [markdown](/items/nifty-line-application-system-542k.md)

confirmed (NIFTY first report, Oct 19); leaked fields still under investigation

2026-10-20

### NIFTY: intruders reached an internal fiber-line application management tool; up to 542,513 @nifty Hikari customers' IDs, names, birth dates, addresses, phones and emails may be exposed

Japanese ISP NIFTY said on Oct 19 that it detected unauthorized external access to its **line application and intake management system** around **10:20 JST on Oct 19** and blocked the source. This is an internal staff tool used to enter applications, not the customer-facing web signup form. Up to **542,513** records may be affected. They belong to customers who applied since 2019 for @nifty Hikari, @nifty MAX Hikari or @nifty au Hikari Plus through channels other than NIFTY's own website. Possible fields: member ID, name, gender, date of birth, address, phone number and email. NIFTY says the system holds no bank account or credit-card data. The investigation is ongoing with outside experts, and NIFTY is reporting to the Personal Information Protection Commission. NIFTY says it will never ask for PINs, passwords or card numbers by email or phone. Treat any such request "from NIFTY" as phishing.

It's the third large Japanese consumer-data disclosure in two days, after [Furusato Choice](/news#furusato-choice-trustbank-4-45m-breach) and [Ymirlink's Cuenote FC](/news#ymirlink-cuenote-fc-9m-records-breach). The notices don't suggest the incidents are connected.

Sources: [NIFTY first report (Oct 19, Japanese)](https://www.nifty.co.jp/newsrelease/nifty202610195434.htm) · [INTERNET Watch](https://internet.watch.impress.co.jp/docs/news/2149373.html)