注：An advanced persistent threat is an adversany that possesses sophisticated levels of expertise and significant resoures which allow it to create opportunties to achieve its obiectives by using multiple attack vectors(e.g.cyber.plysical and deception).These objetives typically include establishing/extending footholds within the imformation technology infrastructure of the targeted organizations for purposes of exfiltrating information，undermining or impeding critical aspects of a mission，program，or organizaion，or positioning itself to carry out these objectives in the future.The advanced persistent threat;(i)pursues its objectives repeatedly over an extended period of time;(ii) adapts to defenders' efforts to resist it;and (iii) is determined to maintain the level of interaction needed to execute its objctives.