Security breach: The Pentagon confirms unauthorized access to the data of more than 3 million people

Personal information about approximately 3.05 million people, including active-duty and reserve military personnel, civilian employees, contractors, veterans and retirees, was exposed following unauthorized access to a system operated by the Defense Manpower Data Center (DMDC), the Pentagon’s personnel archive. The incident affected 2.76 million living people and approximately 294,000 deceased individuals.

According to a U.S. official, access to personally identifiable information was possible between October 2025 and July 2026. The vulnerability was discovered and immediately fixed by the DMDC, but authorities did not specify who was behind the attack.

The exposed data reportedly included Social Security numbers and information about previous employers. For now, there is no evidence that the information was misused.

The incident represents another security problem for U.S. agencies. A few days earlier, the FBI reported that the ShinyHunters hacking group had accessed its classified recruitment portal. A data sample, which reportedly affected approximately 5,000 alleged agents, included names, addresses, telephone numbers and, in some cases, information about family members.