Short for Internal Hostile Structured,
it is a threat defined by Symantec Corporation
to mean an individual or group within an organization that is motivated to disrupt mission operations or exploit assets. An IHS threat is unlikely to act but has the greatest potential to cause damage. An example of an IHS threat might be a highly skilled, disgruntled employee who could benefit from disrupting operations.
Contrast with IHU (Internal Hostile Unstructured).