Hacking of Government Computers Exposed 21.5 Million People

The Office of Personnel Management revealed that 21.5 million people were swept up in a colossal breach of government computer systems that was far more damaging than initially thought, resulting in the theft of a vast trove of personal information, including Social Security numbers and some fingerprints.

Every person given a government background check for the last 15 years was probably affected, the Office of Personnel Management said in announcing the results of a forensic investigation of the episode, whose existence was known but not its sweeping toll. The agency said hackers stole “sensitive information,” including addresses, health and financial history, and other private details, from 19.7 million people who had been subjected to a government background check, as well as 1.8 million others, including their spouses and friends. The theft was separate from, but related to, a breach revealed last month that compromised the personnel data of 4.2 million federal employees, officials said. Both attacks are believed to have originated in China, although senior administration officials declined to pinpoint a perpetrator, except to say that they had indications that the same actor carried out the two hacks.