diff --git a/plugins/providers/virtualbox/cap/configure_disks.rb b/plugins/providers/virtualbox/cap/configure_disks.rb
index b61aa6fdb..736b5b9ae 100644
--- a/plugins/providers/virtualbox/cap/configure_disks.rb
+++ b/plugins/providers/virtualbox/cap/configure_disks.rb
@@ -80,7 +80,7 @@ module VagrantPlugins
         def self.create_disk(machine, disk_config)
           machine.ui.detail("Disk '#{disk_config.name}' not found in guest. Creating and attaching disk to guest...")
           guest_info = machine.provider.driver.show_vm_info
-          disk_provider_config = disk_config.provider_config[:virtualbox]
+          disk_provider_config = disk_config.provider_config[:virtualbox] if disk_config.provider_config
 
           guest_folder = File.dirname(guest_info["CfgFile"])
           disk_ext = "vdi"