Nearly 3 million people impacted by Defense Department data breach exposing sensitive information

Unauthorized users accessed records containing Social Security numbers and military employment information between October 2025 and July 2026.

A breach involving a Defense Department personnel database exposed sensitive personal information belonging to nearly 3 million living and deceased people. Social Security numbers and details about jobs held by military and civilian personnel were also breached, according to a U.S. defense official cited by ABC News.

The Defense Manpower Data Center (DMDC) said unauthorized users accessed personally identifiable information between October 2025 and July 2026. The Pentagon said the vulnerability was discovered and patched, and there is currently no evidence that the exposed information has been misused.

The breach affected approximately 2.76 million living people and 294,000 deceased individuals, according to the defense official cited by ABC News. The DMDC is a major Defense Department repository containing records involving active-duty and reserve service members, civilian employees, contractors, retirees, veterans and military family members.

The agency maintains more than 60 million personnel records, according to Military Times. An earlier report based on a breach notification found that unauthorized users had accessed files containing unencrypted personally identifiable information, including Social Security numbers and military personnel information such as occupational specialty. Defense officials said the vulnerability was remediated after it was discovered in July. The department is offering affected individuals identity-protection and credit-monitoring resources.

The Pentagon incident comes as the FBI investigates a separate possible breach involving FBIJobs.gov, the bureau’s primary employment application website. According to ABC News, an alleged threat actor claimed that information involving FBI employees had been obtained, potentially including names, addresses, contact information, Social Security numbers, dates of birth and emergency-contact information.

The FBI has reportedly been operating on the assumption that employees’ personal information could have been compromised and has begun notifying affected employees. The hacking group ShinyHunters later told The New York Times and 404 Media that it would not release the information as previously threatened, claiming the episode was a marketing campaign. ABC News said it had not independently verified those claims.