An insecure-credentials flaw was found in all openstack-cinder versions before openstack-cinder 14.1.0, all openstack-cinder 15.x.x versions before openstack-cinder 15.2.0 and all openstack-cinder 16.x.x versions before openstack-cinder 16.1.0. When using openstack-cinder with the Dell EMC ScaleIO or VxFlex OS backend storage driver, credentials for the entire backend are exposed in the ``connection_info`` element in all Block Storage v3 Attachments API calls containing that element. This flaw enables an end-user to create a volume, make an API call to show the attachment detail information, and retrieve a username and password that may be used to connect to another user's volume. Additionally, these credentials are valid for the ScaleIO or VxFlex OS Management API, should an attacker disc