  Software-defined networking is considered a promising new paradigm, enabling
more reliable and formally verifiable communication networks. However, this
paper shows that the separation of the control plane from the data plane, which
lies at the heart of Software-Defined Networks (SDNs), introduces a new
vulnerability which we call \emph{teleportation}. An attacker (e.g., a
malicious switch in the data plane or a host connected to the network) can use
teleportation to transmit information via the control plane and bypass critical
network functions in the data plane (e.g., a firewall), and to violate security
policies as well as logical and even physical separations. This paper
characterizes the design space for teleportation attacks theoretically, and
then identifies four different teleportation techniques. We demonstrate and
discuss how these techniques can be exploited for different attacks (e.g.,
exfiltrating confidential data at high rates), and also initiate the discussion
of possible countermeasures. Generally, and given today's trend toward more
intent-based networking, we believe that our findings are relevant beyond the
use cases considered in this paper.
