Permissions Boundary
A permissions boundary is an advanced feature in AWS Identity and Access Management (IAM) that sets the maximum permissions a user or role can have.
Description
In AWS, a permissions boundary acts as a policy that defines the outer limits of what actions a user or role can perform. It is not an IAM policy that grants permissions but rather a policy that restricts permissions. This is particularly useful in large organizations where you want to delegate permission management to teams while maintaining a strict control over what they can grant. For instance, if a team is allowed to create IAM roles, the permissions boundary can prevent them from granting overly broad permissions or access to sensitive resources. This ensures that even if a team member mistakenly assigns permissions, they cannot exceed the defined boundaries. Permissions boundaries can be combined with IAM policies, where the effective permissions are the intersection of the IAM policy and the permissions boundary. This feature enhances security and compliance, especially in environments that require strict governance over access controls. By using permissions boundaries, organizations can better manage risk while allowing flexibility in operations.
Examples
- A finance team can create IAM roles for analysts but is restricted from granting access to billing information due to a defined permissions boundary.
- A development team can manage their own EC2 instances but is limited by a permissions boundary that prevents them from accessing other teams' resources.
Additional Information
- Permissions boundaries are defined using IAM policies, which can include conditions based on tags or resource types.
- Using permissions boundaries effectively helps in achieving compliance with regulations like GDPR or HIPAA by enforcing least privilege access.