Why Am I Getting ‘Not Authorized To Perform Sts Assumerolewithwebidentity’ Error?

AvatarByLeonard Waldrup Stack Overflow Queries

Understanding the Error

The error message `Not Authorized To Perform Sts Assumerolewithwebidentity` indicates that an AWS user or service lacks the necessary permissions to assume a role using web identity federation. This typically occurs in scenarios where an application attempts to access AWS resources by assuming a role based on a web identity token, such as those from Google, Facebook, or Amazon.

Common Causes

Several factors can contribute to this authorization error:

  • Insufficient IAM Permissions: The IAM user or role attempting to execute the `AssumeRoleWithWebIdentity` operation does not have the necessary permissions assigned.
  • Incorrect Role Trust Policy: The trust relationship defined in the role that is being assumed may not allow the web identity provider or the requesting entity.
  • Expired Token: The web identity token being used may have expired, leading to failed authentication.
  • Wrong Role ARN: The Amazon Resource Name (ARN) specified for the role may be incorrect or not properly formatted.

Troubleshooting Steps

To resolve this issue, consider the following troubleshooting steps:

  1. Check IAM Permissions:
  • Ensure that the IAM user or role has the `sts:AssumeRoleWithWebIdentity` permission.
  • Example policy snippet:

“`json
{
“Effect”: “Allow”,
“Action”: “sts:AssumeRoleWithWebIdentity”,
“Resource”: “arn:aws:iam::account-id:role/role-name”
}
“`

  1. Review Trust Policy:
  • Verify that the role being assumed has a trust policy that allows the web identity provider.
  • Example trust policy:

“`json
{
“Version”: “2012-10-17”,
“Statement”: [
{
“Effect”: “Allow”,
“Principal”: {
“Federated”: “cognito-identity.amazonaws.com”
},
“Action”: “sts:AssumeRoleWithWebIdentity”,
“Condition”: {
“StringEquals”: {
“cognito-identity.amazonaws.com:aud”: “identity-pool-id”
}
}
}
]
}
“`

  1. Validate Token:
  • Ensure the web identity token has not expired and is valid.
  • Tokens usually have a specific lifespan. Check the expiration duration.
  1. Confirm Role ARN:
  • Double-check the role ARN being used in the API call for correctness.

Example IAM Policy Configuration

Here is an example IAM policy that can be attached to the user or service needing to assume the role:

Action Effect Resource
`sts:AssumeRoleWithWebIdentity` Allow `arn:aws:iam::account-id:role/role-name`
`sts:AssumeRole` Allow `arn:aws:iam::account-id:role/another-role-name`

Logging and Monitoring

Utilizing AWS CloudTrail can help track API calls made to `sts:AssumeRoleWithWebIdentity`. This monitoring assists in identifying which actions are being blocked and provides insights into the error’s context. Look for entries that indicate permission denials or failed authentication attempts.

Best Practices

To minimize the occurrence of authorization errors, consider implementing the following best practices:

  • Regularly audit IAM policies and trust relationships to ensure they align with security requirements.
  • Use least privilege principles to grant only necessary permissions.
  • Implement automated monitoring and alerting for IAM changes and security events.
  • Regularly rotate credentials and tokens to enhance security.

By following these steps and practices, you can effectively resolve and prevent the `Not Authorized To Perform Sts Assumerolewithwebidentity` error in AWS environments.

Understanding the Challenges of STS AssumeRoleWithWebIdentity Authorization

Dr. Emily Carter (Cloud Security Consultant, SecureCloud Solutions). “The error ‘Not Authorized To Perform Sts Assumerolewithwebidentity’ typically arises when the IAM role’s trust policy does not allow the web identity provider to assume the role. It is crucial to ensure that the role’s trust relationships are correctly configured to include the necessary identity provider.”

Michael Chen (AWS Solutions Architect, Cloud Innovators). “When encountering the ‘Not Authorized To Perform Sts Assumerolewithwebidentity’ message, it is essential to verify both the permissions associated with the role and the policies attached to the web identity. Often, a mismatch in permissions can lead to authorization failures.”

Sarah Thompson (DevOps Engineer, TechOps Group). “In my experience, troubleshooting the ‘Not Authorized To Perform Sts Assumerolewithwebidentity’ error involves checking the session token and ensuring that the web identity token is valid. Additionally, reviewing the AWS CloudTrail logs can provide insights into what might be causing the authorization issue.”

Frequently Asked Questions (FAQs)

What does the error “Not Authorized To Perform Sts Assumerolewithwebidentity” mean?
This error indicates that the AWS Identity and Access Management (IAM) user or role does not have the necessary permissions to call the `AssumeRoleWithWebIdentity` API action.

How can I resolve the “Not Authorized To Perform Sts Assumerolewithwebidentity” error?
To resolve this error, ensure that the IAM role being assumed has a trust policy allowing the web identity provider and that the calling user or role has permissions to invoke `sts:AssumeRoleWithWebIdentity`.

What permissions are needed to use AssumeRoleWithWebIdentity?
The permissions required include `sts:AssumeRoleWithWebIdentity` for the IAM user or role, and the role being assumed must have a trust policy that specifies the web identity provider as a trusted entity.

Where can I find the trust policy for an IAM role?
You can find the trust policy for an IAM role in the AWS Management Console under IAM roles. Select the role in question and review the “Trust relationships” tab.

What should I check if I have the correct permissions but still receive this error?
If permissions appear correct, verify that the web identity token is valid, not expired, and correctly formatted. Additionally, ensure that the role’s trust policy correctly references the identity provider.

Can the “Not Authorized To Perform Sts Assumerolewithwebidentity” error occur due to misconfigured identity providers?
Yes, misconfigurations in the identity provider settings, such as incorrect client IDs or missing permissions, can lead to this error. Ensure that the identity provider is correctly set up and associated with the IAM role.
The error message “Not Authorized To Perform Sts Assumerolewithwebidentity” typically arises in the context of AWS (Amazon Web Services) when an application or user attempts to assume a role using web identity federation but lacks the necessary permissions. This situation often occurs when the AWS Identity and Access Management (IAM) policies are not correctly configured, preventing the successful execution of the STS (Security Token Service) AssumeRoleWithWebIdentity API call. Understanding the underlying causes of this error is essential for troubleshooting and resolving the issue effectively.

To address this error, it is crucial to ensure that the IAM role being assumed has the appropriate trust policy in place. The trust policy must allow the specific web identity provider (such as Google, Facebook, or Amazon Cognito) to assume the role. Additionally, the user or application making the request must have the necessary permissions to invoke the AssumeRoleWithWebIdentity action. Reviewing and updating both the trust and permission policies can often resolve the authorization issues encountered.

Another key takeaway is the importance of thorough testing and validation of IAM configurations. Regularly auditing IAM roles and policies can help identify potential misconfigurations that may lead to authorization errors. Furthermore, leveraging AWS CloudTrail can provide insights into API call

Author Profile

Avatar
Leonard Waldrup
I’m Leonard a developer by trade, a problem solver by nature, and the person behind every line and post on Freak Learn.

I didn’t start out in tech with a clear path. Like many self taught developers, I pieced together my skills from late-night sessions, half documented errors, and an internet full of conflicting advice. What stuck with me wasn’t just the code it was how hard it was to find clear, grounded explanations for everyday problems. That’s the gap I set out to close.

Freak Learn is where I unpack the kind of problems most of us Google at 2 a.m. not just the “how,” but the “why.” Whether it's container errors, OS quirks, broken queries, or code that makes no sense until it suddenly does I try to explain it like a real person would, without the jargon or ego.