def add_acl_permission(session, acl_role_id, perm_type, xpath_id, query_id)
  stdout, stderror, retval = run_cmd(
    session, PCS, "acl", "permission", "add", acl_role_id.to_s, perm_type.to_s,
    xpath_id.to_s, query_id.to_s
  )
  if retval != 0
    if stderror.empty?
      return "Error adding permission"
    else
      return stderror.join("\n").strip
    end
  end
  return ""
end
Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions.