I have a user and I'm trying to impersonate a role for running a service on Kubernetes. However, when I tried using STS to assume the role, I get the following error:
$ aws sts assume-role --role-arn "arn:aws:iam::{ACCOUNT_ID}:role/service-myservice" --role-session-name AWSCLI-Session
An error occurred (AccessDenied) when calling the AssumeRole operation: User: arn:aws:iam::{ACCOUNT_ID}:user/me is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::{ACCOUNT_ID}:role/service-myservice
I find this odd because this user belongs to a user group with the AdministratorAccess permission attached to it, which should give it access to anything on AWS. This is it:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "*",
"Resource": "*"
}
]
}
So, what am I doing wrong here?
CodePudding user response:
What you have here is the IAM policy attached to this User, aka - what is this user is able to do.
You need to set the Trust Relationship as well. This defines which resources or principals is able to use this role/user. Could be Lambda, EC2 or in your case: an IAM User.
See here for example.
The IAM User/Role (in that case, role) you want to assume must have the Trust Relationship as follow:
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Principal": {
"AWS": "arn:aws:iam::<account_id>:role/<role_name>
},
"Action": "sts:AssumeRole"
}
]
}