An acronym of Controlled Unclassified Information.
It is information created or owned by the US government that requires safeguarding. While CUI is not classified information, it is considered sensitive. CUI is governed under a number of government policies and frameworks including the Department of Defense Instruction (DoDI) 5200.48 and Cybersecurity Maturity Model Certification. According to DoDi 5200.48, safeguarding CUI is a shared responsibility between Defense Industrial Base contractors and the Department of Defense.