What is least privilege?, the cloud security principle
Least privilege is the security principle that every identity, human or service, should have the minimum permissions needed to do its job, and no more. It's the single principle that decides how bad a compromise can get: the same breach with a tightly-scoped role is an incident; with a permissive role, it's a headline.
Why What is least privilege? matters
Almost every documented cloud breach has the same shape: an attacker compromises a low-privilege foothold, then uses an over-privileged identity attached to that foothold to escalate. Least privilege is not paranoia, it's the structural defence that decides whether the foothold becomes an incident or a breach.
Common mistakes with What is least privilege?
- Applying broad managed policies (`AdministratorAccess`, `PowerUserAccess`) to roles that need three actions.
- Granting wildcard resource access (`Resource: "*"`) when the role only touches one bucket.
- Ignoring the resource side of access decisions, locking down identity but leaving bucket policies open.
- Treating permission accrual as inevitable instead of running a quarterly access review.