Insider threats are malicious threats that an organization faces from within - employees, former employees, third party vendors, contractors, or business associates. Insider threat actors could steal documents, copy confidential files, install computer viruses, or plant keyloggers on office computers to gain knowledge of passwords.

Every organization is at risk of insider threats. Insider threats are usually the most dangerous vulnerabilities, since they already have some level of access. The insider threat is someone who has had or has access to the organization's networks, data, and/or physical location. Sometimes, the insider is acting unknowingly (for example, using a compromised account for work).