In OpenStack Cyborg before 16.0.1, the Accelerator Request (ARQ) API does not enforce project ownership at any layer. The project_id column in the database is never populated (NULL for every ARQ), database queries have no project filtering, and policy checks are self-referential (the authorize_wsgi decorator compares the caller's project_id with itself rather than the target resource). Any authenticated non-admin user can complete various actions such as deleting ARQs bound to other projects' instances, aka cross-tenant denial of service.
OpenStack Cyborg before 16.0.1 uses rule:allow (check_str='@') as the default policy for multiple API endpoints. This unconditionally authorizes any request carrying a valid Keystone token regardless of roles, project membership, or scope. An authenticated user with zero role assignments can complete various actions such as reprogramming FPGA bitstreams on arbitrary compute nodes via agent RPC.