Major Japanese telco says cyberattack exposed 12 million emails
A major Japanese telecommunications company disclosed a cyberattack that exposed roughly 12 million email accounts across five domestic internet service providers. The breach affected systems handling customer email accounts, webmail services, and stored messages.
Why this matters: Email is not just a communication channel. For most people it is a master key — password resets, bank notices, medical correspondence, and years of personal history all flow through it. Twelve million accounts is a large number, but the damage depends on what attackers can now reach. If stored messages were accessed, the exposure goes far beyond contact details. Customers of all five affected ISPs should assume their inboxes were seen and act accordingly.
Who should care: Cybersecurity · Privacy officers · Administrators
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