Direct answer
An external-access finding identifies a policy path for review, not necessarily unintended access or actual use. Compare the principal and resource with the documented sharing agreement and assess effective permissions.
Identify the resource and principal
Record the account, resource, external principal, granted action and owner from the finding. Determine whether the recipient is an approved partner, a public principal or an unexpected account. Avoid publishing account IDs or policy contents in broad channels.
Reference: AWS IAM Access Analyzer.
Review the policy path
Inspect the resource policy, conditions and other applicable controls using the provider's access-analysis tools. A finding can describe potential access even when other restrictions apply; a lack of recent activity does not make a permanent grant necessary.
- Confirm the business reason and expiration of sharing.
- Distinguish read, write and administrative permissions.
- Check supporting encryption-key access when relevant.
Validate with controlled identities
If the engagement permits, use an approved external test principal and a synthetic resource to verify the intended and denied operations. Do not assume control of a partner account or access real customer data without its owner agreeing to scope.
Remediate and verify
Narrow or remove unintended sharing through change control, then check the updated analysis finding and retest the authorized integration. Track justified exceptions with an owner, scope and review date.
Assessment limits
Access-analysis tools assess supported resource types and policies, and results can depend on configuration. A finding is not proof that data was accessed; review relevant audit evidence separately.
Frequently asked questions
Does an external access finding prove a breach?
No. It identifies a potential permission path. Determine whether it is intended and investigate actual use separately.
Should all cross-account access be removed?
No. Some integrations are intentional; limit and document the access required for the approved purpose.
Primary sources and further reading
These guides combine published security guidance with practical assessment planning. Adapt checks to the owner's policy, environment, and authorized scope.
This guide was prepared with AI assistance using the linked sources and illustrative examples. Check current vendor guidance and your environment before making changes.