Dormant High impact Data breach Checked 5d ago

Aflac Japan data breach exposes 4.38 million customers

Aflac's Japanese subsidiary discovered that hackers had repeatedly accessed its policyholder portal between June 15 and June 25, 2026. The company says the intruders reached personal, policy, and bank account details for about 4.38 million customers and agents. Aflac disclosed the breach to regulators and the SEC in late June and is notifying affected people.

Started
Jun 15, 2026
Latest activity
Jun 25, 2026
Attributed to
Not confirmedNo credible attribution yet
Where
Japan
Sectors
Finance
Scale
about 4.38 million Aflac Japan policyholders and agents

Current status

As of the July 1 disclosure and July 26 follow-up reporting, Aflac said the unauthorized access was stopped and it is notifying customers and regulators, with no report yet of ongoing intrusion.

Dormant: No new confirmed activity for a while, and nobody has called an official all clear.

Impact

Attackers repeatedly accessed Aflac Japan's policyholder portal and obtained personal information, insurance policy details, and bank account data for millions of customers and agents.

What to do

Aflac Japan customers should watch for an official notification letter from Aflac and monitor bank and insurance accounts for unusual activity rather than clicking links in unsolicited emails claiming to be from Aflac.

Timeline

  1. Aug 9, 2026

    No new confirmed activity reported, so this incident moved to dormant while it stays open.

    Dormant
  2. Jul 1, 2026

    Aflac confirmed to regulators that policy details and personal and banking information had been compromised.

    Containedinfosecurity-magazine.com
  3. Jun 30, 2026

    Aflac disclosed that its Japan subsidiary discovered unauthorized access to its policyholder portal that occurred between June 15 and June 25, exposing data on 4.38 million customers.

    Containedbleepingcomputer.com

Sources

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