  Advanced persistent threat (APT) is widely acknowledged to be the most
sophisticated and potent class of security threat. APT refers to knowledgeable
human attackers that are organized, highly sophisticated and motivated to
achieve their objectives against a targeted organization(s) over a prolonged
period. Strategically-motivated APTs or S-APTs are distinct in that they draw
their objectives from the broader strategic agenda of third parties such as
criminal syndicates, nation-states, and rival corporations. In this paper we
review the use of the term - Advanced Persistent Threat - and present a formal
definition. We then draw on military science, the science of organized
conflict, for a theoretical basis to develop a rigorous and holistic model of
the stages of an APT operation which we subsequently use to explain how S-APTs
execute their strategically motivated operations using tactics, techniques and
procedures. Finally, we present a general disinformation model, derived from
situation awareness theory, and explain how disinformation can be used to
attack the situation awareness and decision making of not only S-APT operators,
but also the entities that back them.
