Which type of hacker has no legitimate access to a computer system?

The type of hacker who has no legitimate access to a computer system is an outsider hacker. Outsider hackers operate from an external position, attempting to gain unauthorized access to systems without any prior permission or legitimate credentials. They typically exploit vulnerabilities in software or use various techniques such as phishing, social engineering, or brute force attacks to breach security measures and access sensitive information.

In contrast, insider hackers, such as employees or contractors, already possess legitimate access to the system, which they may misuse. Script kiddies are usually less skilled individuals who use pre-existing tools and scripts created by more experienced hackers; they may not necessarily be outsiders in terms of their knowledge, although they typically lack sophisticated skills. Ethical hackers, on the other hand, are skilled professionals hired to test and secure systems legitimately, ensuring that they are protected against potential attacks. Therefore, the key distinction for an outsider hacker lies in their lack of authorized access to the systems they target.