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Confidence MediumJun 28, 2026nifty.com

NIFTY Corporation Affected by KDDI Corporation Data Breach

PatternExternal actor · Hacking · Confidentiality impact

NIFTY Corporation, a Japanese internet service provider, was impacted by a data breach originating from an email system provided by KDDI Corporation. Threat actors gained unauthorized access to this shared system by exploiting a vulnerability in third-party software. This led to the potential exposure of up to 14.2 million email addresses and passwords across all affected ISPs. NIFTY Corporation customers' email addresses and passwords may have been compromised.

Signal date
Jun 28, 2026
Updated
Jun 29, 2026
Confidence
Medium
Sources
4 sources
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Nifty

Domain
nifty.com
Sector
Information
Signals
1 linked

Signal context

First seen: Jun 28, 2026

Last updated: Jun 29, 2026

Status: Public signal

Key points

  • NIFTY Corporation was impacted by a data breach originating from KDDI Corporation's email system.
  • Unauthorized access to the shared email system by exploiting a third-party software vulnerability.
  • Potential exposure of email addresses and passwords for NIFTY Corporation customers.

Signal analysis

Beta

This analysis groups the signal by industry, likely incident action and impacted security area. It helps compare this signal with other published signals without treating the labels as final determinations.

Affected organization
Nifty logo
Nifty

Sector: Information

Likely country: Location not provided

Estimated
Threat source
Hacking activity

Watch internet-facing systems, credential abuse and exploit activity.

  • Source type: outside the affected organization
Business impact
Potential data exposure

Impact area: Confidentiality

Likely asset: User or customer data

Trend context
72 signals with similar action pattern
  • 31 signals in the same sector
  • 93 signals with the same likely impact area
  • 1 signal linked to this organization/domain
Mentioned entities
NiftyData DisclosureNIFTY Corporation AffectedKDDI Corporation Data Breach NIFTYCorporationJapaneseKDDI Corporation. ThreatISPs. NIFTY CorporationNIFTY CorporationKDDI Corporation

External sources

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BIGLOBE Inc., a Japanese internet service provider, was impacted by a data breach originating from an email system provided by KDDI Corporation. Threat actors gained unauthorized access to this shared system by exploiting a vulnerability in third-party software. This led to the potential exposure of up to 14.2 million email addresses and passwords across all affected ISPs. BIGLOBE Inc. customers' email addresses and passwords may have been compromised.

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STNet, Inc. Affected by KDDI Corporation Data Breach

STNet, Inc., a Japanese internet service provider, was impacted by a data breach originating from an email system provided by KDDI Corporation. Threat actors gained unauthorized access to this shared system by exploiting a vulnerability in third-party software. This led to the potential exposure of up to 14.2 million email addresses and passwords across all affected ISPs. STNet customers' email addresses and passwords may have been compromised.