/info/me.json sometimes doesn't provide full information about the user

Steps to reproduce:
1. Open <admin node>/info/me.json in a browser

Actual Results:
[...] "userRole":"ROLE_USER_ADMIN","user":{"provider":null,"name":null,"email":null,"username":"admin"}}

Expected Results:
provider, name and email should be provided correctly

Workaround (if any):