Defense Manpower Data Center Data Breach
The Defense Manpower Data Center (DMDC), the primary human resource data repository for the United States Department of Defense, disclosed a major security incident involving unencrypted files exposed to unauthorized network access.
Exposed Data Types
7- Social security numbers
- Names
- Dates of birth
- Physical addresses
- Phone numbers
- Email addresses
- Employment records
About This Breach
Originating from a vulnerability in a legacy file-sharing system active between October 2025 and July 16, 2026, the incident impacted approximately 3.05 million individuals, consisting of 2.76 million living service members, veterans, contractors, and civilians, alongside 294,000 deceased military personnel. Compromised records contained plaintext Social Security numbers (SSNs), full names, dates of birth, contact addresses, demographic attributes, and military occupational specialty codes.
Verification and editorial method
LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.
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