Pentagon Data Breach Exposed Unencrypted Social Security Numbers for Months, Affecting More Than 3 Million People

The Pentagon has confirmed that a breach at its Defense Manpower Data Center exposed personal records of more than 3 million people (Credit: David B. Gleason/WikiMedia Commons)

For roughly nine months, unencrypted personal information including Social Security numbers was accessible to unauthorised users through a DMDC file-sharing system. The Defense Department did not find the vulnerability until 16 July.

The exposure affected 2.76 million living people and another 294,000 deceased people, a US defence official said. The files belonged to the Defense Manpower Data Center, or DMDC, one of the Pentagon's main repositories for personnel, manpower, training and financial records.