AWS IAM Roles Anywhere: Secure Identity for External and Hybrid Workloads

AWS IAM Roles Anywhere is an AWS Identity and Access Management (IAM) feature that allows workloads running outside of AWS (on-premises, other clouds, edge locations, or devices) to securely assume IAM roles using X.509 certificates, instead of long-term AWS access keys.

Key characteristics

• Uses public key infrastructure (PKI) and X.509 certificates
• Issues temporary AWS credentials via STS
• Eliminates the need to store long-lived IAM user access keys outside AWS
• Works for non-AWS compute environments

Before This Service, What Was the Solution in AWS?

Before IAM Roles Anywhere, AWS did not have a native service for non-AWS workloads to assume IAM roles directly.

Common AWS-native approaches used earlier

IAM Users with Access Keys

• Create an IAM user
• Generate Access Key ID and Secret Access Key
• Store them on on-prem servers or apps

Security risk (long-lived credentials)

STS AssumeRole with Static Credentials

• IAM user used to call sts:AssumeRole
• Still required long-term credentials to bootstrap

Custom Federation via SAML / OIDC

• Mostly designed for human users, not machine workloads
• Complex for service-to-service authentication

Conclusion:
 There was no first-class AWS solution for secure, certificate-based authentication for external workloads.

Cloud Provider Alternatives

• Azure Managed Identity
• GCP Workload Identity existed

AWS lacked equivalent for non-AWS workloads

Why Do We Have IAM Roles Anywhere Now?

AWS introduced IAM Roles Anywhere to address:

1. Growing hybrid cloud architectures
2. Increased adoption of multi-cloud
3. Security best practice: zero trust + short-lived credentials
4. Customer demand for AWS-native identity for external workloads
5. This aligns AWS with:
   • Azure Managed Identities
   • GCP Workload Identity Federation

What Problem Does It Solve?

Core Problems Solved:

AWS IAM Roles Anywhere Key Components

Trust Anchor

1. Represents a trusted certificate authority (CA)
2. Can be:
   • Self-managed root CA
   • Enterprise CA
   • AWS Private CA
3. AWS validates client certificates against the Trust Anchor

IAM Role

• Standard IAM role
• Trust policy explicitly allows rolesanywhere.amazonaws.com
• Permissions defined via IAM policies

Profile

1. Logical mapping between:
   • Trust Anchor
   • One or more IAM Roles
2. Controls:
   • Session duration
   • Which roles external workloads may assume

X.509 Certificate

1. Installed on external workload
2. Contains:
   • Public key
   • Subject / identity metadata
   • Corresponding private key never leaves workload

AWS Roles Anywhere Credential Helper

1. CLI utility provided by AWS
2. Handles:
   • Certificate authentication
   • STS calls
   • Credential rotation
   • Outputs credentials compatible with AWS SDKs

Domain Solutions

A. Banking & Financial Services

Use Case:

• Core banking apps running on-prem
• Regulatory restrictions prevent cloud migration

Solution:

1. On-prem apps authenticate using X.509 certs
2. Assume IAM roles to:
   • Access S3 for reports
   • Push data to Kinesis
   • Invoke AWS APIs securely

Benefits:

• No static secrets
• Meets PCI-DSS & RBI security requirements
• Full CloudTrail auditing

B. Financial Trading / Risk Systems

Use Case:

• Low-latency trading engines in private data centers
• Need AWS analytics and ML services

Solution:

1. Use IAM Roles Anywhere to access:
   • Amazon S3
   • Athena
   • SageMaker endpoints

Benefits:

• Short-lived credentials reduce blast radius
• No dependency on human IAM users

C. Telecom

Use Case:

• OSS/BSS systems running in telecom data centers
• Network probes & monitoring agents

Solution:

1. Each system gets its own certificate
2. Role-based access to:
   • CloudWatch
   • S3
   • DynamoDB

Benefits:

• Per-device identity
• Easy revocation if a device is compromised
• Scales to thousands of nodes

Implementation Steps

1. AWS Console

Step 1: Create a Trust Anchor

• IAM → Roles Anywhere
• Create Trust Anchor
  • Name: enterprise-root-ca
  • Source type: Certificate Bundle
  • Upload Root CA certificate (X.509) rootCA.pem

Step 2: Create an IAM Role

• IAM → Roles
• Trusted entity type: Custom trust policy

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "rolesanywhere.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

• Attach required policies (AmazonS3ReadOnlyAccess, etc.)

Step 3: Create a Profile

• IAM Roles Anywhere → Profiles
• Create Profile
  • Profile name: onprem-app-profile
  • Associate IAM role(s)
  • Associate Trust Anchor
  • Set session duration (e.g., 1 hour)
• Define session duration

Step 4: Configure External Workload

• Install AWS Roles Anywhere credential helper

curl -o aws_signing_helper https://rolesanywhere.amazonaws.com/releases/latest/linux_amd64/aws_signing_helper
chmod +x aws_signing_helper

• Configure AWS CLI Credential Process

Create or update ~/.aws/config:

[profile rolesanywhere]
credential_process = /path/aws_signing_helper credential-process \
  --certificate /path/workload.crt \
  --private-key /path/workload.key \
  --trust-anchor-arn arn:aws:rolesanywhere:... \
  --profile-arn arn:aws:rolesanywhere:... \
  --role-arn arn:aws:iam::ACCOUNT:role/MyRole

• Validate Access

aws sts get-caller-identity --profile rolesanywhere

2. AWS CLI

• Create Trust Anchor

aws rolesanywhere create-trust-anchor \
  --name my-trust-anchor \
  --source sourceType=CERTIFICATE_BUNDLE,sourceData=@rootCA.pem

• Create IAM Role

> Create a file named rolesanywhere-trust-policy.json:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "rolesanywhere.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}

This trust policy explicitly allows AWS IAM Roles Anywhere to assume the role.

> Create IAM role

aws iam create-role \
  --role-name RolesAnywhereExternalWorkloadRole \
  --assume-role-policy-document file://rolesanywhere-trust-policy.json \
  --description "IAM role for external workloads using IAM Roles Anywhere"

> Attach policy to IAM role

aws iam attach-role-policy \
  --role-name RolesAnywhereExternalWorkloadRole \
  --policy-arn arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess

> Verify role configuration

aws iam get-role \
  --role-name RolesAnywhereExternalWorkloadRole

• Create Profile

aws rolesanywhere create-profile \
  --name my-profile \
  --role-arns arn:aws:iam::123456789012:role/MyRole

• Obtain Credentials (External Host)

aws_signing_helper credential-process \
  --certificate cert.pem \
  --private-key key.pem \
  --trust-anchor-arn  \
  --profile-arn  \
  --role-arn 

Interview Questions and Answers

Additional Interview Questions