AWS IAM Permissions are the fine-grained authorizations that specify which actions an identity (user, group, or role) can perform on specific AWS resources. They form the foundation of AWS's access control system, allowing organizations to implement the principle of least privilege across their cloud environments.
IAM Permissions are access control statements implemented as JSON policy documents attached to IAM identities. Each statement contains essential elements: an Effect ("Allow" or "Deny"), Actions (specific API operations), Resources (AWS resources targeted), and optional Conditions (contextual requirements). Unlike traditional role-based systems, AWS IAM employs attribute-based access control, enabling more dynamic permissions based on user, resource, and environmental attributes.
IAM permissions operate through JSON policy documents attached to identities (users, groups, roles) or resources. A policy document contains one or more statements, each defining a specific permission. Here's a simple example:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "s3:GetObject",
"Resource": "arn:aws:s3:::example-bucket/*"
}
]
}
This policy allows the identity to retrieve objects from the specified S3 bucket. The permission model is additive, with explicit denies taking precedence over allows. When a principal makes a request to AWS, the authorization system evaluates all applicable policies to determine whether the request should be allowed or denied.
AWS IAM uses a deny-by-default model, meaning that access to resources is denied unless explicitly allowed through permissions. This approach ensures that new AWS services or API actions aren't automatically accessible without deliberate authorization.
AWS IAM supports several types of policies that work together to define permissions:
Policy Type | Attached To | Primary Purpose |
---|---|---|
Identity-based Policies | Users, groups, roles | Control what actions an identity can perform |
Resource-based Policies | AWS resources | Control who can access a specific resource |
Permission Boundaries | Users and roles | Set maximum permissions an identity can have |
These are the main policy types you'll encounter when working with AWS IAM. For comprehensive information about all policy types, including Service Control Policies and Session Policies, refer to the AWS IAM Policy Types documentation.
The IAM permissions model revolves around six key elements: the Principal (user, role, or service) requests access to specific Resources (identified by ARNs) to perform Actions (API operations like s3:GetObject
). The system handles Authentication (verifying identity via credentials) and Authorization (evaluating policies to permit/deny access), while Conditions enable context-based restrictions (time, IP, MFA). Understanding these components is essential for crafting effective IAM policies.
For AWS-based email systems like those using Amazon SES, carefully designed IAM permissions are essential for security and operational integrity:
Email Sending Permissions such as ses:SendEmail
and ses:SendRawEmail
control who can send messages. These can be scoped to specific verified identities to control which domains and email addresses can be used for sending.
Configuration Management Permissions like ses:CreateConfigurationSet
and ses:UpdateConfigurationSetEventDestination
determine who can modify SES settings, which should typically be limited to administrative users.
Notification Processing Permissions enable systems to process bounce and complaint feedback through permissions like sns:Subscribe
and sns:Receive
.
Monitoring Permissions such as ses:GetSendStatistics
and cloudwatch:GetMetricData
allow teams to track email performance without necessarily having permission to send email or change configurations.
The AWS IAM Access Analyzer provides policy evaluation capabilities, or you can use the AWS CLI command aws iam get-policy
combined with get-policy-version
to review policy contents. The IAM console also provides visual tools for examining permissions.
The AWS CloudTrail service logs all API calls with details about the request, including the identity, the action requested, and whether it was allowed or denied. The IAM console includes a policy simulator to test policies before applying them.
Yes, through session policies used with assumed roles and through condition elements in policies. Conditions can include time-based restrictions, source IP address requirements, resource tags, and many other attributes.
Email communication is part of your product! Don't let it ruin your user's experience with your brand