Hackers breach Pentagon database holding data on nearly 3 million military personnel

Hackers infiltrated a Pentagon personnel database, potentially compromising the personal information of approximately 3 million military and civilian personnel, according to ABC News on September 29. The exposed data includes Social Security numbers and details about the positions and duties of the affected individuals. According to a U.S. Defense Department official, the breach impacted 2.76 million living individuals and around 294,000 deceased personnel.

The unauthorized access to the Defense Manpower Data Center (DMDC) information system spanned from October 2025 to July 2026. A limited number of unauthorized users breached the system. The DMDC, which is one of the Pentagon's primary repositories of personnel data, stores information on service members, reservists, civilian employees, contractors, veterans, retirees, and military dependents.

It contains over 60 million records. As of now, Pentagon officials have not found any evidence that the stolen information has been misused. Those whose data might have been compromised are being offered identity protection and credit monitoring services. On September 23, the ShinyHunters hacking group claimed responsibility for stealing data belonging to almost all FBI employees and applicants.

Reuters partially verified the authenticity of the leaked data, which included names, addresses, Social Security numbers, and employment details.