A breach of the Pentagon’s sprawling personnel database exposed sensitive information belonging to a massive swath of military personnel, including Social Security numbers and details about the jobs they held, according to a U.S. defense official.

The breach affected 2.76 million living people and another 294,000 who are deceased, the official said. The scope and sensitivity of the exposed information could raise national security concerns, particularly because the files included details about the jobs performed by military and civilian personnel.

“A Defense Manpower Data Center (DMDC) information system experienced unauthorized access of personally identifiable information by a small number of unauthorized users between October 2025 and July 2026. Upon discovery, DMDC immediately remediated the vulnerability,” the official said.

The Defense Manpower Data Center serves as one of the Pentagon’s main repositories for personnel records, holding information on active-duty and reserve troops, civilian employees, contractors, retirees, veterans and military family members.

The agency maintains more than 60 million personnel records. Military Times first reported the breach last week.

The unauthorized access stretched from October 2025 until July, when DMDC discovered the vulnerability and patched the affected system, according to the defense official, adding there’s no evidence yet that any of the exposed data has been misused.

Defense officials said they have found no evidence so far that the exposed information has been misused and are offering identity protection and credit monitoring resources.

The news of the Pentagon breach comes as the FBI sent a notice to employees on Friday outlining their response to a breach of its jobs portal FBIJobs.gov. 

An threat actor said it would publish data including FBI employees’ names, home address, personal and work contact information, Social Security numbers, date of birth and emergency contact information, sources tell ABC News, and the bureau is operating as if every FBI employee’s personal information was compromised. 

Employees who were impacted have also begun to be notified, and the FBI said that the impacted system — FBIJobs.gov — was unclassified. 

The FBI also issued a warning for those who might be impacted, advising them to maintain situational awareness and to not answer suspicious calls. There will also be internal briefings for employees who have been impacted. 

It also says, according to the warning described to ABC News, that employees should not talk to the media and if the media is “trespassing,” employees should call 911.