OpenWISP IPAM has broken object-level authorization: ExportSubnetView lets a member of one organization export another organization's subnet and all its IP addresses

Summary OpenWISP IPAM is multi-tenant: every Subnet belongs to an organization, and API access is scoped to the organizations a user belongs to. The CSV export endpoint, ExportSubnetView, omits the organization-membership check that its import sibling performs, and loads the subnet by primary key...