A cybersecurity exploit is

the damage done by a hacker who deeply penetrates a vulnerable network or system and takes malicious action

the vulnerability in system security procedures, design, implementation, or control that a hacker uses to harm a system

the means by which a hacker capitalizes on a cybersecurity vulnerability to gain access to and harm a system

the unwarranted access a hacker gains to a vulnerable network, from a remote and untraceable location