Permissions, Privileges, and Access Controls
The system.temporary route in Drupal 8.x before 8.1.10 and 8.2.0-beta1 through 8.2.0-rc1 does not properly check for "Export configuration" permission, which allows remote authenticated users to bypass intended access restrictions and read a full config export via unspecified vectors.
CWE-264 - Permissions Privileges and Access Controls
CWE 264 (permissions, privileges, and access controls) is not a weakness in and of itself, rather it is a category of weaknesses related to the management of permissions, privileges, and other security features used to perform access control. If not addressed, the weaknesses in this category allow attackers to gain privileges for an unintended sphere of control, access sensitive information, and execute arbitrary commands.