title: Error when Ec2 running as a role tries to get a Session Token in AWS
body: <p>I'm running a app on an EC2 using a role with the the permissions:</p>
  
  <pre><code>"sts:GetSessionToken",
  "sts:AssumeRole"
  </code></pre>
  
  <p>When I try to obtain temporary credentials using that role, I get the error:</p>
  
  <pre><code>Cannot call GetSessionToken with session credentials (Service: AWSSecurityTokenService; Status Code: 403; Error Code: AccessDenied;
  </code></pre>
  
  <p>Am I missing one or more permissions for the role to be able to obtain temporary session credentials?</p>