AWS IAM Least Privilege

Least privilege means granting only the permissions required to perform a task, and no additional permissions.

Practical workflow

1. Identify the workload or human task.
2. Start with a narrowly scoped role where practical.
3. Restrict actions to the services and operations actually required.
4. Restrict resources and conditions when possible.
5. Observe real access patterns.
6. Remove unused permissions.
7. Re-test the workload after every reduction.

AWS recommends temporary credentials for workloads through IAM roles, federation for human access, MFA, and regular review of unused access. IAM Access Analyzer can help generate and validate more precise policies.

Common mistake

A policy that works is not necessarily a secure policy. Action: "*" or broad resource access can hide the real permission requirements and increase blast radius.

Troubleshooting connection

When you see AccessDenied, first identify principal → action → resource → condition/context before changing permissions.

Connected knowledge

IAM troubleshooting → S3 access troubleshooting → secure upload architecture.