The Defense Federal Acquisition Regulation Supplement (DFARS) is a supplement to the Federal Acquisition Regulation (FAR) system that provides acquisition compliance requirements for the Department of Defense (DoD) procurement process. DFARS uses the same cybersecurity standards of the National Institute of Standards and Technology (NIST 800-171).

DFARS sets cybersecurity standards for companies in the safeguarding their information systems that store or transmit information. As of 2018, all government contractors processing, storing, or transmitting controlled but unclassified information (CUI) must meet the Defense Federal Acquisition Regulation Supplement (DFARS) security requirements or jeopardize losing their contracts with the DoD.