A flaw in a file sharing system permitted unauthorized users to reach files stored on a server operated by the Defense Manpower Data Center (DMDC), the central personnel registry of the U.S. Department of Defense.
The incident exposed records belonging to more than 3 million people. The DMDC maintains over 60 million records covering active-duty and reserve military personnel, civilian employees, contractors, retirees, veterans, family members, and other individuals affiliated with the department.
All exposed information was stored without encryption. The dataset included full names, Social Security numbers, dates of birth, contact information, gender, race, and functional details such as each person’s military occupational specialty.
Unauthorized access occurred between October 2025 and July 2026, a period of approximately nine months before the organization detected the problem. The DMDC identified the flaw on 16 July 2026, applied an immediate remediation, restored the system, and activated its privacy and cybersecurity incident response procedures.
Victim notification letters dated 18 September were mailed two months after discovery. Every affected individual is being provided one year of free credit monitoring and identity restoration services through the contractor IDX, which works with the Department of Defense.
No public attribution has been made regarding the responsible parties or the motive behind the access. According to published materials, investigators have found no evidence that the exposed information was misused.


