AdminstratorAccess is not enough to assume a role using cli?

Question

I've a IAM user
It's part of group FullAdmins
This group has the policy 'AdministratorAccess' 
This policy allows ALL actions on EVERY and EACH resources

```
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "*",
            "Resource": "*"
        }
    ]
}
```

I configured cli to use this iam user

But I cannot assume a role

```
aws sts assume-role --role-arn arn:aws:iam::888......380:role/cli --role-session-name prove-template-ipv6
```

I got 
> An error occurred (AccessDenied) when calling the AssumeRole operation: User: arn:aws:iam::667.....831:user/myIamUserName is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::888...380:role/cli

Why?

My IAM user is exentially god ! can do everything it wants, but ... cannot assume role!??!

Accepted Answer

Hello,

Here is an article explaining how you can allow an IAM user to assume a role in your AWS account: https://repost.aws/knowledge-center/iam-assume-role-cli

In order for an IAM user(arn:aws:iam::667.....831:user/myIamUserName) to assume the role (arn:aws:iam::888...380:role/cli). You must update the trust relationship policy of the role. This will enable the IAM user to assume a role.

```
{
  "Version": "2012-10-17",
  "Statement": {
    "Effect": "Allow",
    "Principal": {
      "AWS": "arn:aws:iam::667.....831:user/myIamUserName"
    },
    "Action": "sts:AssumeRole"
  }
}
```

Answer

> This policy allows ALL actions on EVERY and EACH resources

Allows actions in your account only.

The error message `User: arn:aws:iam::667.....831:user/myIamUserName is not authorized to perform: sts:AssumeRole on resource: arn:aws:iam::888...380:role/cli` shows that the user in account **667.....831** is trying to assume a role in account **888...380**

The steps to follow, in both accounts, are in https://repost.aws/knowledge-center/cross-account-access-iam

AdminstratorAccess is not enough to assume a role using cli?

Relevant content