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answer: direct
beat: dev-practices
source: 1 article · updated: July 7, 2026
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When did KDDI find out, and how fast did it respond?

KDDI says it detected the intrusion on June 17, 2026, and blocked the attacker's access that same day while rolling out technical defensive measures. The company notified affected ISPs and Japanese regulators as part of its response, though the disclosures detailing the full scope followed over the subsequent weeks.

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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