The (1) ListNetworkACL and (2) listNetworkACLLists APIs in Apache CloudStack before 4.2.1 allow remote authenticated users to list network ACLS for other users via a crafted request.
In Apache CloudStack 4.1.0 and 4.1.1, when calling the CloudStack API call listProjectAccounts as a regular, non-administrative user, the user is able to see information for accounts other than their own.