The majority of computer crimes are committed by:

An insider threat is a malicious threat to an organization that comes from people within the organization, such as employees, former employees, contractors or business associates, who have inside information concerning the organization's security practices, data and computer systems. The threat may involve fraud, the theft of confidential or commercially valuable information, the theft of intellectual property, or the sabotage of computer systems. The insider threat comes in three categories:
I. Malicious insiders, which are people who take advantage of their access to inflict harm on an organization.
II. Negligent insiders, which are people who make errors and disregard policies, which place their organizations at risk.
III. Infiltrators, who are external actors that obtain legitimate access credentials without authorization.