Plane is an open-source project management tool. In 1.3.1 and earlier, EntityAssetEndpoint at the public project asset endpoint /api/public/assets/v2/anchor/{anchor}/ requires authentication for write operations but does not verify workspace or project membership. An authenticated user who knows a published project's public DeployBoard.anchor can create FileAsset records in that project and soft-delete existing assets by identifier, allowing cross-workspace file injection, storage abuse, and data loss. The issue is fixed in version 1.4.0.