Just-in-Time (JIT) access is a privilege control that grants elevated permissions only when they are needed and only for a short, defined period. Instead of leaving admin rights permanently active, JIT uses role activation, temporary credentials, or session brokering to make access expire automatically. This reduces standing privilege, which is a common security weakness in cloud and infrastructure environments.
JIT matters because stolen credentials or abused admin accounts have less time to be useful. In real defenses, it is used for production servers, databases, Kubernetes clusters, and cloud roles, with approvals, MFA, and detailed logging. Attackers may try to exploit weak approval rules, overly broad roles, or long access windows, so JIT is only effective when sessions are tightly bounded and revocation is fast.