Vulnerability
In plain terms
A weakness that an attacker could exploit.
Going deeper
A vulnerability is a flaw in code, configuration, or design that could be used to compromise security. Identifying and patching them is ongoing work.
Under the hood
Tracked via CVEs and scored by CVSS; severity and exploitability guide prioritization.
Examples
Unpatched software, misconfigurations, CVEs, injection flaws, weak passwords.
Think of it like...
Like an unlocked window that a burglar could climb through.