AWS IAM Policy Evaluation: Why Allow Can Still Mean Access Denied

Understand AWS IAM policy evaluation by tracing the caller, action, resource and request context. Learn why an Allow statement can still result in Access Denied when applicable boundaries, session policies, conditions or organization controls restrict the request. Work through a missing boundary permission and a publishing job that attempts a forbidden deletion. Distinguish grant paths, explicit denial and cross-account access, then verify required work succeeds without weakening the intended restriction. Chapters 00:00 An Allow statement is not the whole access decision 00:57 Capture the request before choosing a repair 01:48 Identity policies and resource policies provide different grant paths 02:46 Missing permission and an explicit Deny are different failures 03:39 A permissions boundary limits an identity grant 04:36 A session restriction is not an extra permission grant 05:30 The principal named in a resource grant matters 06:29 Organization controls have principal and resource scopes 07:23 Conditions decide whether a statement applies 08:16 An intended deny can reveal a wrong application operation 09:12 Cross-account resource access needs both sides to allow 10:08 Trace, change and verify the actual access decision 11:07 Explain the decision, not just the presence of Allow Official AWS references AWS documentation: https://docs.aws.amazon.com/IAM/lates... AWS documentation: https://docs.aws.amazon.com/IAM/lates... AWS documentation: https://docs.aws.amazon.com/IAM/lates... AWS documentation: https://docs.aws.amazon.com/IAM/lates... AWS documentation: https://docs.aws.amazon.com/IAM/lates... #AWS #CloudArchitecture