# Keio ransomware attack disrupts card payments at some stores

_Published Monday, September 28, 2026 at 2:19 AM EDT · Security, Products · Latest · Tier 2 — Notable_

![Ransomware Attack Hits Japan's Keio Corporation Group, Disrupting Card Payments at Retail Stores — Primary](https://img.biggo.com/HhYlfyI8-UBsuNvSllHumxLChpfFYWqkc7tXBHpqYXI/fit/1200/0/sm/0/aHR0cHM6Ly9pbWcuYmdvLm9uZS9uZXdzLWltYWdlL2FpX2dlbmVyYXRlZC8yMDI2LTA5LzFiYWY1MTJiLThkNDktNDBlNS1hODNlLTZiOTcwMzM5OTJjNF8xNzkwNTY4NTk4X2RlZmF1bHQuanBn.jpg)

A ransomware attack on servers at Keio Corporation group companies has left some of the Japanese company's retail stores unable to accept credit card payments. Keio announced the attack on September 26 after detecting it early that day, according to BigGo Finance.

The company isolated affected networks and notified police. Its business systems have also experienced disruptions, chiefly in retail. Train operations continue because their servers run on a separate system. Keio is working with outside experts to determine how the attackers entered and whether confidential or customer information was taken; it has not confirmed a data leak.

## Sources

- [finance.biggo.com](https://finance.biggo.com/news/1baf512b-8d49-40e5-a83e-6b97033992c4)

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Canonical: https://techandbusiness.org/newswire/kXaHEwfCipqYA-GmriSCum
Published: 2026-09-28T06:19:23.357Z
Story chronology: 2026-09-26T00:00:00.000Z
Retrieved: 2026-09-28T09:07:22.629Z
Publisher: Tech & Business (techandbusiness.org)