Advanced persistent threat
An adversary or collection of adversaries collaborating, opportunistically overlapping, or inadvertently converging that uses multiple attack vectors to achieve their objectives, including cyber, physical, and deception. Such adversaries use tactics, techniques, and procedures that display sophisticated levels of expertise and significant resources to achieve their objectives. These objectives typically include establishing and extending footholds within the IT infrastructure of the targeted organizations for purposes of exfiltrating information; undermining or impeding critical aspects of a mission, program, or organization; or positioning itself to carry out these objectives in the future. The advanced persistent threat pursues its objectives repeatedly over an extended period, adapts to defenders' efforts to resist it, and is determined to maintain the level of interaction needed to execute its objectives.