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XCCDF
Cisco NX OS Switch L2S Security Technical Implementation Guide
Cisco NX OS Switch L2S Security Technical Implementation Guide
An XCCDF Benchmark
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Prose
22 rules organized in 22 groups
SRG-NET-000148-L2S-000015
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must uniquely identify all network-connected endpoint devices before establishing any connection.
High Severity
<VulnDiscussion>Controlling LAN access via 802.1x authentication can assist in preventing a malicious user from connecting an unauthorized PC to a switch port to inject or receive data from the network without detection.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000168-L2S-000019
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must authenticate all VLAN Trunk Protocol (VTP) messages with a hash function using the most secured cryptographic algorithm available.
Medium Severity
<VulnDiscussion>VLAN Trunk Protocol (VTP) provides central management of VLAN domains, thus reducing administration in a switched network. When configuring a new VLAN on a VTP server, the VLAN is distributed through all switches in the domain. This reduces the need to configure the same VLAN everywhere. VTP pruning preserves bandwidth by preventing VLAN traffic (unknown MAC, broadcast, multicast) from being sent down trunk links when not needed, that is, there are no access switch ports in neighboring switches belonging to such VLANs. An attack can force a digest change for the VTP domain enabling a rogue device to become the VTP server, which could allow unauthorized access to previously blocked VLANs or allow the addition of unauthorized switches into the domain. Authenticating VTP messages with a cryptographic hash function can reduce the risk of the VTP domain's being compromised.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000331-L2S-000001
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must be configured for authorized users to select a user session to capture.
Medium Severity
<VulnDiscussion>Without the capability to select a user session to capture/record or view/hear, investigations into suspicious or harmful events would be hampered by the volume of information captured. The volume of information captured may also adversely impact the operation for the network. Session audits may include port mirroring, tracking websites visited, and recording information and/or file transfers.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000332-L2S-000002
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must be configured for authorized users to remotely view, in real time, all content related to an established user session from a component separate from The Cisco switch.
Medium Severity
<VulnDiscussion>Without the capability to remotely view/hear all content related to a user session, investigations into suspicious user activity would be hampered. Real-time monitoring allows authorized personnel to take action before additional damage is done. The ability to observe user sessions as they are happening allows for interceding in ongoing events that after-the-fact review of captured content would not allow.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000343-L2S-000016
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must authenticate all endpoint devices before establishing any connection.
Medium Severity
<VulnDiscussion>Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. For distributed architectures (e.g., service-oriented architectures), the decisions regarding the validation of authentication claims may be made by services separate from the services acting on those decisions. In such situations, it is necessary to provide authentication decisions (as opposed to the actual authenticators) to the services that need to act on those decisions. This requirement applies to applications that connect either locally, remotely, or through a network to an endpoint device (including, but not limited to, workstations, printers, servers (outside a datacenter), VoIP Phones, and VTC CODECs). Gateways and SOA applications are examples of where this requirement would apply. Device authentication is a solution enabling an organization to manage devices. It is an additional layer of authentication ensuring only specific pre-authorized devices can access the system.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000021
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have Root Guard enabled on all switch ports connecting to access layer switches and hosts.
Low Severity
<VulnDiscussion>Spanning Tree Protocol (STP) does not provide any means for the network administrator to securely enforce the topology of the switched network. Any switch can be the root bridge in a network. However, a more optimal forwarding topology places the root bridge at a specific predetermined location. With the standard STP, any bridge in the network with a lower bridge ID takes the role of the root bridge. The administrator cannot enforce the position of the root bridge but can set the root bridge priority to 0 in an effort to secure the root bridge position. The root guard feature provides a way to enforce the root bridge placement in the network. If the bridge receives superior STP Bridge Protocol Data Units (BPDUs) on a root guard-enabled port, root guard moves this port to a root-inconsistent STP state and no traffic can be forwarded across this port while it is in this state. To enforce the position of the root bridge it is imperative that root guard is enabled on all ports where the root bridge should never appear.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000022
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have BPDU Guard enabled on all user-facing or untrusted access switch ports.
Medium Severity
<VulnDiscussion>If a rogue switch is introduced into the topology and transmits a Bridge Protocol Data Unit (BPDU) with a lower bridge priority than the existing root bridge, it will become the new root bridge and cause a topology change, rendering the network in a suboptimal state. The STP PortFast BPDU guard enhancement allows network designers to enforce the STP domain borders and keep the active topology predictable. The devices behind the ports that have STP PortFast enabled are not able to influence the STP topology. At the reception of BPDUs, the BPDU guard operation disables the port that has PortFast configured. The BPDU guard transitions the port into errdisable state and sends a log message.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000023
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have STP Loop Guard enabled.
Medium Severity
<VulnDiscussion>The Spanning Tree Protocol (STP) loop guard feature provides additional protection against STP loops. An STP loop is created when an STP blocking port in a redundant topology erroneously transitions to the forwarding state. In its operation, STP relies on continuous reception and transmission of BPDUs based on the port role. The designated port transmits BPDUs, and the non-designated port receives BPDUs. When one of the ports in a physically redundant topology no longer receives BPDUs, the STP conceives that the topology is loop free. Eventually, the blocking port from the alternate or backup port becomes a designated port and moves to a forwarding state. This situation creates a loop. The loop guard feature makes additional checks. If BPDUs are not received on a non-designated port and loop guard is enabled, that port is moved into the STP loop-inconsistent blocking state.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000024
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have Unknown Unicast Flood Blocking (UUFB) enabled.
Medium Severity
<VulnDiscussion>Access layer switches use the Content Addressable Memory (CAM) table to direct traffic to specific ports based on the VLAN number and the destination MAC address of the frame. When a router has an Address Resolution Protocol (ARP) entry for a destination host and forwards it to the access layer switch and there is no entry corresponding to the frame's destination MAC address in the incoming VLAN, the frame will be sent to all forwarding ports within the respective VLAN, which causes flooding. Large amounts of flooded traffic can saturate low-bandwidth links, causing network performance issues or complete connectivity outage to the connected devices. Unknown unicast flooding has been a nagging problem in networks that have asymmetric routing and default timers. To mitigate the risk of a connectivity outage, the Unknown Unicast Flood Blocking (UUFB) feature must be implemented on all access layer switches. The UUFB feature will block unknown unicast traffic flooding and only permit egress traffic with MAC addresses that are known to exit on the port.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000025
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have DHCP snooping for all user VLANs to validate DHCP messages from untrusted sources.
Medium Severity
<VulnDiscussion>In an enterprise network, devices under administrative control are trusted sources. These devices include the switches, routers, and servers in the network. Host ports and unknown DHCP servers are considered untrusted sources. An unknown DHCP server on the network on an untrusted port is called a spurious DHCP server, any device (PC, Wireless Access Point) that is loaded with DHCP server enabled. The DHCP snooping feature determines whether traffic sources are trusted or untrusted. The potential exists for a spurious DHCP server to respond to DHCPDISCOVER messages before the real server has time to respond. DHCP snooping allows switches on the network to trust the port a DHCP server is connected to and not trust the other ports. The DHCP snooping feature validates DHCP messages received from untrusted sources and filters out invalid messages as well as rate-limits DHCP traffic from trusted and untrusted sources. DHCP snooping feature builds and maintains a binding database, which contains information about untrusted hosts with leased IP addresses, and it utilizes the database to validate subsequent requests from untrusted hosts. Other security features, such as IP Source Guard and Dynamic Address Resolution Protocol (ARP) Inspection (DAI), also use information stored in the DHCP snooping binding database. Hence, it is imperative that the DHCP snooping feature is enabled on all VLANs.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000026
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have IP Source Guard enabled on all user-facing or untrusted access switch ports.
Medium Severity
<VulnDiscussion>IP Source Guard provides source IP address filtering on a Layer 2 port to prevent a malicious host from impersonating a legitimate host by assuming the legitimate host's IP address. The feature uses dynamic DHCP snooping and static IP source binding to match IP addresses to hosts on untrusted Layer 2 access ports. Initially, all IP traffic on the protected port is blocked except for DHCP packets. After a client receives an IP address from the DHCP server, or after static IP source binding is configured by the administrator, all traffic with that IP source address is permitted from that client. Traffic from other hosts is denied. This filtering limits a host's ability to attack the network by claiming a neighbor host's IP address.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000362-L2S-000027
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have Dynamic Address Resolution Protocol (ARP) Inspection (DAI) enabled on all user VLANs.
Medium Severity
<VulnDiscussion>DAI intercepts Address Resolution Protocol (ARP) requests and verifies that each of these packets has a valid IP-to-MAC address binding before updating the local ARP cache and before forwarding the packet to the appropriate destination. Invalid ARP packets are dropped and logged. DAI determines the validity of an ARP packet based on valid IP-to-MAC address bindings stored in the DHCP snooping binding database. If the ARP packet is received on a trusted interface, the switch forwards the packet without any checks. On untrusted interfaces, the switch forwards the packet only if it is valid.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000001
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have Storm Control configured on all host-facing switchports.
Low Severity
<VulnDiscussion>A traffic storm occurs when packets flood a LAN, creating excessive traffic and degrading network performance. Traffic storm control prevents network disruption by suppressing ingress traffic when the number of packets reaches a configured threshold levels. Traffic storm control monitors ingress traffic levels on a port and drops traffic when the number of packets reaches the configured threshold level during any one-second interval.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000002
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have IGMP or MLD Snooping configured on all VLANs.
Low Severity
<VulnDiscussion>IGMP and MLD snooping provides a way to constrain multicast traffic at Layer 2. By monitoring the IGMP or MLD membership reports sent by hosts within a VLAN, the snooping application can set up Layer 2 multicast forwarding tables to deliver specific multicast traffic only to interfaces connected to hosts interested in receiving the traffic, thereby significantly reducing the volume of multicast traffic that would otherwise flood the VLAN.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000004
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must enable Unidirectional Link Detection (UDLD) to protect against one-way connections.
Medium Severity
<VulnDiscussion>In topologies where fiber optic interconnections are used, physical misconnections can occur that allow a link to appear to be up when there is a mismatched set of transmit/receive pairs. When such a physical misconfiguration occurs, protocols such as STP can cause network instability. UDLD is a layer 2 protocol that can detect these physical misconfigurations by verifying that traffic is flowing bidirectionally between neighbors. Ports with UDLD enabled periodically transmit packets to neighbor devices. If the packets are not echoed back within a specific time frame, the link is flagged as unidirectional and the interface is shut down.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000007
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have all disabled switch ports assigned to an unused VLAN.
Medium Severity
<VulnDiscussion>It is possible that a disabled port that is assigned to a user or management VLAN becomes enabled by accident or by an attacker and as a result gains access to that VLAN as a member.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000008
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must not have the default VLAN assigned to any host-facing switch ports.
Medium Severity
<VulnDiscussion>In a VLAN-based network, switches use the default VLAN (i.e., VLAN 1) for in-band management and to communicate with other networking devices using Spanning-Tree Protocol (STP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP)—all untagged traffic. As a consequence, the default VLAN may unwisely span the entire network if not appropriately pruned. If its scope is large enough, the risk of compromise can increase significantly.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000009
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have the default VLAN pruned from all trunk ports that do not require it.
Medium Severity
<VulnDiscussion>The default VLAN (i.e., VLAN 1) is a special VLAN used for control plane traffic such as Spanning-Tree Protocol (STP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP). VLAN 1 is enabled on all trunks and ports by default. With larger campus networks, care needs to be taken about the diameter of the STP domain for the default VLAN. Instability in one part of the network could affect the default VLAN, thereby influencing control-plane stability and therefore STP stability for all other VLANs.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000010
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must not use the default VLAN for management traffic.
Medium Severity
<VulnDiscussion>Switches use the default VLAN (i.e., VLAN 1) for in-band management and to communicate with directly connected switches using Spanning-Tree Protocol (STP), Dynamic Trunking Protocol (DTP), VLAN Trunking Protocol (VTP), and Port Aggregation Protocol (PAgP)—all untagged traffic. As a consequence, the default VLAN may unwisely span the entire network if not appropriately pruned. If its scope is large enough, the risk of compromise can increase significantly.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000011
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have all user-facing or untrusted ports configured as access switch ports.
Medium Severity
<VulnDiscussion>Double encapsulation can be initiated by an attacker who has access to a switch port belonging to the native VLAN of the trunk port. Knowing the victim's MAC address and with the victim attached to a different switch belonging to the same trunk group, thereby requiring the trunk link and frame tagging, the malicious user can begin the attack by sending frames with two sets of tags. The outer tag that will have the attacker's VLAN ID (probably the well-known and omnipresent default VLAN) is stripped off by the switch, and the inner tag that will have the victim's VLAN ID is used by the switch as the next hop and sent out the trunk port.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000012
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must have the native VLAN assigned to an ID other than the default VLAN for all 802.1q trunk links.
Medium Severity
<VulnDiscussion>VLAN hopping can be initiated by an attacker who has access to a switch port belonging to the same VLAN as the native VLAN of the trunk link connecting to another switch that the victim is connected to. If the attacker knows the victim’s MAC address, it can forge a frame with two 802.1q tags and a layer 2 header with the destination address of the victim. Since the frame will ingress the switch from a port belonging to its native VLAN, the trunk port connecting to the victim’s switch will simply remove the outer tag because native VLAN traffic is to be untagged. The switch will forward the frame on to the trunk link unaware of the inner tag with a VLAN ID of which the victim’s switch port is a member.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
SRG-NET-000512-L2S-000013
1 Rule
<GroupDescription></GroupDescription>
The Cisco switch must not have any switchports assigned to the native VLAN.
Low Severity
<VulnDiscussion>Double encapsulation can be initiated by an attacker who has access to a switch port belonging to the native VLAN of the trunk port. Knowing the victim’s MAC address and with the victim attached to a different switch belonging to the same trunk group, thereby requiring the trunk link and frame tagging, the malicious user can begin the attack by sending frames with two sets of tags. The outer tag that will have the attacker’s VLAN ID (probably the well-known and omnipresent default VLAN) is stripped off by the switch, and the inner tag that will have the victim’s VLAN ID is used by the switch as the next hop and sent out the trunk port.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>