An SDN controller can manage and configure SDN-enabled devices using protocols such as SNMP and NETCONF. If an SDN-aware router or switch received erroneous configuration information that was altered by a malicious user, interfaces could be disabled, erroneous IP addresses configured, services removed—all resulting a network disruption or even an outage. Hence, it is imperative to secure the management plane by encrypting all southbound API management-plane traffic or deploying an out-of-band network for this traffic to traverse.
Determine if the southbound API management-plane traffic traverses an out-of-band path. If not, review the SDN controller configuration to verify that southbound API management-plane traffic is encrypted using a using a FIPS-validated cryptographic module. If the southbound API management-plane traffic does not traverse an out-of-band path and is not encrypted using a FIPS-validated cryptographic module, this is a finding. Note: FIPS-validated cryptographic modules are listed on the NIST Cryptographic Module Validation Program's (CMVP) validation list.
Deploy an out-of-band network to provision paths between SDN controller and SDN-enabled devices as well as all hypervisor hosts that compose the SDN infrastructure to provide transport for southbound API management-plane traffic. An alternative is to configure the SDN controller to encrypt all southbound API management-plane traffic using a FIPS-validated cryptographic module. Implement a cryptographic module which has a validation certification and is listed on the NIST Cryptographic Module Validation Program's (CMVP) validation list.