WASHINGTON (Realist English). The Pentagon has confirmed a breach of one of its key personnel systems — the Defense Manpower Data Center (DMDC). According to a US official, the leak affected 2.76 million living individuals and another 294,000 deceased.
Scale and Nature of the Breach
The compromised information includes Social Security numbers and details of positions held by military and civilian Pentagon employees. According to CNN, in some cases this involves “occupational specialty” data, and this information was not encrypted.
DMDC is one of the primary repositories of Pentagon personnel records. Its systems contain data on more than 60 million people: active-duty service members and reservists, civilian employees, contractors, veterans, retirees, and military family members.
Timeline
Unauthorized access occurred from October 2025 to July 2026. The vulnerability was discovered and patched in July 2026. According to Military.com, the flaw was in a file exchange system, which allowed outsiders to access files on a server containing unencrypted personal information.
Pentagon’s Response
“The information system of the Department of Defense’s Defense Manpower Data Center (DMDC) experienced unauthorized access to personally identifiable information by a small number of unauthorized users between October 2025 and July 2026. Upon discovery, DMDC immediately patched the vulnerability,” a Defense Department spokesperson said.
The Pentagon states that it has so far found no evidence that the compromised information was used for unlawful purposes. Affected individuals are being offered identity protection services and one year of credit monitoring.
Expert Risk Assessment
Cybersecurity experts warn that the exposed records could be combined with other datasets to identify service members, facilitate phishing attacks, or gather intelligence.
Justin Sherman, head of the consulting firm Global Cyber Strategies, told CNN that access to such information could enable profiling, phishing, and approaches by foreign intelligence services if the information falls into the hands of a foreign adversary.
Related FBI Incident
The Pentagon breach became known against the backdrop of a separate hack affecting the FBI’s recruitment website — FBIJobs.gov. The hacker group ShinyHunters claimed it gained access to the data of all bureau employees, including names, home addresses, contacts, Social Security numbers, and dates of birth.
The FBI is operating on the assumption that the personal data of every employee may have been compromised. The bureau issued a warning to employees advising them not to respond to suspicious calls and to refrain from communicating with the media.
