The report notes that “hackers accessed reports containing portions of the plan, not the entire document.” According to an anonymous official, the United States and South Korea are reportedly discussing whether their existing plans under OPLAN 5027 have to be changed or overhauled based on the data breach. The South Koreans reportedly discovered that the plan had been stolen while investigating an unrelated cyber attack last fall. The attack reportedly targeted a vaccine server at the South Korean military’s cyber command.