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answer: direct
beat: dev-practices
source: 1 article · updated: July 7, 2026
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What data was exposed, and was it protected?

Email addresses and account passwords. Some passwords were stored hashed or encrypted, but reporting on the incident notes the extent of any plaintext exposure is unclear. KDDI's own statement is careful hedging: there "remains a possibility that customers' email addresses and passwords were obtained by unauthorized third parties."

Answered in

One Vendor Flaw Just Exposed 14.2 Million Logins Across Six Japanese ISPs

A flaw in one unnamed vendor's software let attackers into a shared email platform, exposing up to 14.2 million accounts across six Japanese ISPs.

Crashtech Editorial July 7, 2026 Development Best Practices

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