Authorized access can expose information, meetings, facilities or systems that outsiders cannot ordinarily reach. Risk can involve deliberate misuse, compromised accounts or accidental disclosure, so access alone does not establish malicious intent.
Organizations manage the risk through proportionate access controls, separation of duties, monitoring and fair investigation. Evidence must distinguish observed actions from assumptions about a person's motives or responsibility.
ELI5
An insider threat is a risk connected to access someone already has inside an organization. The concern can involve mistakes as well as deliberate misuse, and it is not a label that proves a person did something wrong.
For example, a staff member might accidentally share a private document with the wrong group. Limiting unnecessary access and keeping a clear record can help prevent or investigate the problem without guessing about intent.
Does legitimate access prove wrongdoing?
No. Access is one condition relevant to risk, while responsibility requires evidence about actual events.
Are insider threats always deliberate?
No. Mistakes and compromised accounts can also create harm.

