The shared clipboard enables users to share data between the host and the guest. Enabling the clipboard in Bidirectional mode enables the guest to read and write the host clipboard. The Host to Guest mode and the Guest to Host mode limit the access to one direction. If the guest is able to access the host clipboard it can also potentially access sensitive data from the host which is shared over the clipboard.

If the guest is able to read from or write to the host clipboard then a remote user connecting to the guest over the network will also gain this ability, which may not be appropriate. As a consequence, the shared clipboard is disabled for new machines.