Least privilege in IAM

Least privilege means granting only the permissions required for a task—no wildcards on * in production unless carefully justified and scoped.

Practical rules

• Start with AWS managed job-function policies, then trim
• Scope Resource to specific ARNs—not "*" for sensitive services
• Separate prod and sandbox accounts (Organizations preview later)
• Use roles for apps; ban shared user access keys on servers
• Review IAM Access Analyzer findings periodically

Anti-patterns

• Attaching AdministratorAccess to every developer
• Root access keys in CI pipelines
• Public S3 buckets via overly permissive bucket policies (see storage lessons)

Security mindset continues on Cybersecurity.

List users with access keys

# Audit sandbox account — disable unused keys
aws iam generate-credential-report
# After report is ready:
aws iam get-credential-report --output text | head

Practice: Perform IAM steps in the IAM Console or with the AWS CLI in a sandbox account only.

Important interview questions and answers

1. Q: Least privilege in one sentence?
   A: Give identities the minimum permissions needed to perform their job—nothing more.
2. Q: Why avoid AdministratorAccess for devs?
   A: One compromised key or mistaken CLI command can delete entire environments.

Self-check

1. Name two least-privilege practices for IAM users.
2. Why should applications use roles instead of user access keys?

Pitfall: AdministratorAccess on developers—one typo can delete production.