| V-221091 | High | The Cisco perimeter switch must be configured to restrict it from accepting outbound IP packets that contain an illegitimate address in the source address field via egress filter or by enabling Unicast Reverse Path Forwarding (uRPF). | A compromised host in an enclave can be used by a malicious platform to launch cyberattacks on third parties. This is a common practice in "botnets", which are a collection of compromised... |
| V-221121 | High | The Cisco PE switch providing MPLS Virtual Private Wire Service (VPWS) must be configured to have the appropriate virtual circuit identification (VC ID) for each attachment circuit. | VPWS is an L2VPN technology that provides a virtual circuit between two PE switches to forward Layer 2 frames between two customer-edge switches or switches through an MPLS-enabled IP core. The... |
| V-221126 | High | The Cisco PE switch must be configured to block any traffic that is destined to the IP core infrastructure. | IP/MPLS networks providing VPN and transit services must provide, at the least, the same level of protection against denial-of-service (DoS) attacks and intrusions as Layer 2 networks. Although... |
| V-221122 | High | The Cisco PE switch providing Virtual Private LAN Services (VPLS) must be configured to have all attachment circuits defined to the virtual forwarding instance (VFI) with the globally unique VPN ID assigned for each customer VLAN. | VPLS defines an architecture that delivers Ethernet multipoint services over an MPLS network. Customer Layer 2 frames are forwarded across the MPLS core via pseudowires using IEEE 802.1q Ethernet... |
| V-221087 | High | The Cisco perimeter switch must be configured to deny network traffic by default and allow network traffic by exception. | A deny-all, permit-by-exception network communications traffic policy ensures that only connections that are essential and approved are allowed.
This requirement applies to both inbound and... |
| V-221080 | High | The Cisco switch must be configured to restrict traffic destined to itself. | The route processor handles traffic destined to the switch—the key component used to build forwarding paths and is instrumental with all network management functions. Hence, any disruption or DoS... |
| V-221117 | High | The Cisco PE switch must be configured to have each Virtual Routing and Forwarding (VRF) instance bound to the appropriate physical or logical interfaces to maintain traffic separation between all MPLS L3VPNs. | The primary security model for an MPLS L3VPN infrastructure is traffic separation. The service provider must guarantee the customer that traffic from one VPN does not leak into another VPN or into... |
| V-221118 | High | The Cisco PE switch must be configured to have each Virtual Routing and Forwarding (VRF) instance with the appropriate Route Target (RT). | The primary security model for an MPLS L3VPN as well as a VRF-lite infrastructure is traffic separation. Each interface can only be associated to one VRF, which is the fundamental framework for... |
| V-221095 | Medium | The Cisco perimeter switch must be configured to block all packets with any IP options. | Packets with IP options are not fast switched and henceforth must be punted to the switch processor. Hackers who initiate denial-of-service (DoS) attacks on switches commonly send large streams of... |
| V-221094 | Medium | The Cisco perimeter switch must be configured to filter egress traffic at the internal interface on an inbound direction. | Access lists are used to separate data traffic into that which it will route (permitted packets) and that which it will not route (denied packets). Secure configuration of switches makes use of... |
| V-221093 | Medium | The Cisco perimeter switch must be configured to filter ingress traffic at the external interface on an inbound direction. | Access lists are used to separate data traffic into that which it will route (permitted packets) and that which it will not route (denied packets). Secure configuration of switches makes use of... |
| V-221092 | Medium | The Cisco perimeter switch must be configured to filter traffic destined to the enclave in accordance with the guidelines contained in DoD Instruction 8551.1. | Vulnerability assessments must be reviewed by the System Administrator, and protocols must be approved by the Information Assurance (IA) staff before entering the enclave.
ACLs are the first line... |
| V-221090 | Medium | The Cisco perimeter switch must be configured to block inbound packets with source Bogon IP address prefixes. | Packets with Bogon IP source addresses should never be allowed to traverse the IP core. Bogon IP networks are RFC1918 addresses or address blocks that have never been assigned by the IANA or have... |
| V-221073 | Medium | The Cisco switch must be configured to use keys with a duration not exceeding 180 days for authenticating routing protocol messages. | If the keys used for routing protocol authentication are guessed, the malicious user could create havoc within the network by advertising incorrect routes and redirecting traffic. Some routing... |
| V-221099 | Medium | The Cisco perimeter switch must be configured to block all outbound management traffic. | For in-band management, the management network must have its own subnet in order to enforce control and access boundaries provided by Layer 3 network nodes, such as switches and firewalls.... |
| V-221098 | Medium | The Cisco perimeter switch must be configured to have Proxy ARP disabled on all external interfaces. | When Proxy ARP is enabled on a switch, it allows that switch to extend the network (at Layer 2) across multiple interfaces (LAN segments). Because proxy ARP allows hosts from different LAN... |
| V-221081 | Medium | The Cisco switch must be configured to drop all fragmented Internet Control Message Protocol (ICMP) packets destined to itself. | Fragmented ICMP packets can be generated by hackers for DoS attacks such as Ping O' Death and Teardrop. It is imperative that all fragmented ICMP packets are dropped. |
| V-221105 | Medium | The Cisco BGP switch must be configured to reject inbound route advertisements from a customer edge (CE) switch for prefixes that are not allocated to that customer. | As a best practice, a service provider should only accept customer prefixes that have been assigned to that customer and any peering autonomous systems. A multi-homed customer with BGP speaking... |
| V-221104 | Medium | The Cisco BGP switch must be configured to reject inbound route advertisements for any prefixes belonging to the local autonomous system (AS). | Accepting route advertisements belonging to the local AS can result in traffic looping or being black-holed, or at a minimum, using a non-optimized path. |
| V-221107 | Medium | The Cisco BGP switch must be configured to reject outbound route advertisements for any prefixes belonging to the IP core. | Outbound route advertisements belonging to the core can result in traffic either looping or being black holed, or at a minimum, using a non-optimized path. |
| V-221106 | Medium | The Cisco BGP switch must be configured to reject outbound route advertisements for any prefixes that do not belong to any customers or the local autonomous system (AS). | Advertisement of routes by an autonomous system for networks that do not belong to any of its customers pulls traffic away from the authorized network. This causes a denial of service (DoS) on the... |
| V-221100 | Medium | The Cisco switch must be configured to only permit management traffic that ingresses and egresses the out-of-band management (OOBM) interface. | The OOBM access switch will connect to the management interface of the managed network elements. The management interface can be a true OOBM interface or a standard interface functioning as the... |
| V-221103 | Medium | The Cisco BGP switch must be configured to reject inbound route advertisements for any Bogon prefixes. | Accepting route advertisements for Bogon prefixes can result in the local autonomous system (AS) becoming a transit for malicious traffic as it will in turn advertise these prefixes to neighbor... |
| V-221102 | Medium | The Cisco BGP switch must be configured to use a unique key for each autonomous system (AS) that it peers with. | If the same keys are used between eBGP neighbors, the chance of a hacker compromising any of the BGP sessions increases. It is possible that a malicious user exists in one autonomous system who... |
| V-221141 | Medium | The Cisco multicast Designated switch (DR) must be configured to set the shortest-path tree (SPT) threshold to infinity to minimalize source-group (S, G) state within the multicast topology where Any Source Multicast (ASM) is deployed. | ASM can have many sources for the same groups (many-to-many). For many receivers, the path via the RP may not be ideal compared with the shortest path from the source to the receiver. By default,... |
| V-221143 | Medium | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to authenticate all received MSDP packets. | MSDP peering with customer network switches presents additional risks to the core, whether from a rogue or misconfigured MSDP-enabled switch. MSDP password authentication is used to validate each... |
| V-221123 | Medium | The Cisco PE switch providing Virtual Private LAN Services (VPLS) must be configured to have traffic storm control thresholds on CE-facing interfaces. | A traffic storm occurs when packets flood a VPLS bridge, creating excessive traffic and degrading network performance. Traffic storm control prevents VPLS bridge disruption by suppressing traffic... |
| V-221120 | Medium | The Cisco PE switch providing MPLS Layer 2 Virtual Private Network (L2VPN) services must be configured to authenticate targeted Label Distribution Protocol (LDP) sessions used to exchange virtual circuit (VC) information using a FIPS-approved message authentication code algorithm. | LDP provides the signaling required for setting up and tearing down pseudowires (virtual circuits used to transport Layer 2 frames) across an MPLS IP core network. Using a targeted LDP session,... |
| V-221128 | Medium | The Cisco PE switch must be configured to ignore or drop all packets with any IP options. | Packets with IP options are not fast-switched and therefore must be punted to the switch processor. Hackers who initiate denial-of-service (DoS) attacks on switches commonly send large streams of... |
| V-221071 | Medium | The Cisco switch must be configured to enforce approved authorizations for controlling the flow of information within the network based on organization-defined information flow control policies. | Information flow control regulates where information is allowed to travel within a network and between interconnected networks. The flow of all network traffic must be monitored and controlled so... |
| V-237760 | Medium | The Cisco perimeter switch must be configured to suppress Router Advertisements on all external IPv6-enabled interfaces. | Many of the known attacks in stateless autoconfiguration are defined in RFC 3756 were present in IPv4 ARP attacks. To mitigate these vulnerabilities, links that have no hosts connected such as the... |
| V-221079 | Medium | The Cisco switch must be configured to protect against or limit the effects of denial-of-service (DoS) attacks by employing control plane protection. | The Route Processor (RP) is critical to all network operations because it is the component used to build all forwarding paths for the data plane via control plane processes. It is also... |
| V-221084 | Medium | The Cisco switch must be configured to have Internet Control Message Protocol (ICMP) unreachable messages disabled on all external interfaces. | The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Switches automatically send ICMP messages under a wide variety of conditions. Host unreachable... |
| V-221085 | Medium | The Cisco switch must be configured to have Internet Control Message Protocol (ICMP) redirect messages disabled on all external interfaces. | The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Switches automatically send ICMP messages under a wide variety of conditions. Redirect ICMP... |
| V-221142 | Medium | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to only accept MSDP packets from known MSDP peers. | MSDP peering with customer network switches presents additional risks to the DISN Core, whether from a rogue or misconfigured MSDP-enabled switch. To guard against an attack from malicious MSDP... |
| V-221082 | Medium | The Cisco switch must be configured to have Gratuitous ARP disabled on all external interfaces. | A gratuitous ARP is an ARP broadcast in which the source and destination MAC addresses are the same. It is used to inform the network about a host IP address. A spoofed gratuitous ARP message can... |
| V-221074 | Medium | The Cisco switch must be configured to use encryption for routing protocol authentication. | A rogue switch could send a fictitious routing update to convince a site's perimeter switch to send traffic to an incorrect or even a rogue destination. This diverted traffic could be analyzed to... |
| V-221088 | Medium | The Cisco perimeter switch must be configured to enforce approved authorizations for controlling the flow of information between interconnected networks in accordance with applicable policy. | Information flow control regulates authorized information to travel within a network and between interconnected networks. Controlling the flow of network traffic is critical so it does not... |
| V-221089 | Medium | The Cisco perimeter switch must be configured to only allow incoming communications from authorized sources to be routed to authorized destinations. | Unrestricted traffic may contain malicious traffic that poses a threat to an enclave or to other connected networks. Additionally, unrestricted traffic may transit a network, which uses bandwidth... |
| V-221078 | Medium | The Cisco switch must not be configured to have any feature enabled that calls home to the vendor. | Call home services will routinely send data such as configuration and diagnostic information to the vendor for routine or emergency analysis and troubleshooting. There is a risk that transmission... |
| V-221116 | Medium | The Cisco MPLS switch must be configured to have TTL Propagation disabled. | The head end of the label-switched path (LSP), the label edge switch (LER) will decrement the IP packet's time-to-live (TTL) value by one and then copy the value to the MPLS TTL field. At each... |
| V-221139 | Medium | The Cisco multicast Designated switch (DR) must be configured to filter the Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Report messages to allow hosts to join a multicast group only from sources that have been approved by the organization. | Real-time multicast traffic can entail multiple large flows of data. Large unicast flows tend to be fairly isolated (i.e., someone doing a file download here or there), whereas multicast can have... |
| V-221110 | Medium | The Cisco BGP switch must be configured to use the maximum prefixes feature to protect against route table flooding and prefix de-aggregation attacks. | The effects of prefix de-aggregation can degrade switch performance due to the size of routing tables and also result in black-holing legitimate traffic. Initiated by an attacker or a... |
| V-221075 | Medium | The Cisco switch must be configured to authenticate all routing protocol messages using NIST-validated FIPS 198-1 message authentication code algorithm. | A rogue switch could send a fictitious routing update to convince a site's perimeter switch to send traffic to an incorrect or even a rogue destination. This diverted traffic could be analyzed to... |
| V-221131 | Medium | The Cisco switch must be configured to enforce a Quality-of-Service (QoS) policy to limit the effects of packet flooding denial-of-service (DoS) attacks. | DoS is a condition when a resource is not available for legitimate users. Packet flooding distributed denial-of-service (DDoS) attacks are referred to as volumetric attacks and have the objective... |
| V-221132 | Medium | The Cisco multicast switch must be configured to disable Protocol Independent Multicast (PIM) on all interfaces that are not required to support multicast routing. | If multicast traffic is forwarded beyond the intended boundary, it is possible that it can be intercepted by unauthorized or unintended personnel. Limiting where, within the network, a given... |
| V-221133 | Medium | The Cisco multicast switch must be configured to bind a Protocol Independent Multicast (PIM) neighbor filter to interfaces that have PIM enabled. | PIM is a routing protocol used to build multicast distribution trees for forwarding multicast traffic across the network infrastructure. PIM traffic must be limited to only known PIM neighbors by... |
| V-221127 | Medium | The Cisco PE switch must be configured with Unicast Reverse Path Forwarding (uRPF) loose mode enabled on all CE-facing interfaces. | The uRPF feature is a defense against spoofing and denial-of-service (DoS) attacks by verifying if the source address of any ingress packet is reachable. To mitigate attacks that rely on forged... |
| V-221140 | Medium | The Cisco multicast Designated switch (DR) must be configured to limit the number of mroute states resulting from Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Host Membership Reports. | The current multicast paradigm can let any host join any multicast group at any time by sending an IGMP or MLD membership report to the DR. In a Protocol Independent Multicast (PIM) Sparse Mode... |
| V-221072 | Medium | The Cisco switch must be configured to implement message authentication for all control plane protocols. | A rogue switch could send a fictitious routing update to convince a site's perimeter switch to send traffic to an incorrect or even a rogue destination. This diverted traffic could be analyzed to... |
| V-237757 | Medium | The Cisco switch must not be configured to use IPv6 Site Local Unicast addresses. | As currently defined, site local addresses are ambiguous and can be present in multiple sites. The address itself does not contain any indication of the site to which it belongs. The use of... |
| V-221119 | Medium | The Cisco PE switch must be configured to have each VRF with the appropriate Route Distinguisher (RD). | An RD provides uniqueness to the customer address spaces within the MPLS L3VPN infrastructure. The concept of the VPN-IPv4 and VPN-IPv6 address families consists of the RD prepended before the IP... |
| V-221125 | Medium | The Cisco PE switch must be configured to limit the number of MAC addresses it can learn for each Virtual Private LAN Services (VPLS) bridge domain. | VPLS defines an architecture that delivers Ethernet multipoint services over an MPLS network. Customer Layer 2 frames are forwarded across the MPLS core via pseudowires using IEEE 802.1q Ethernet... |
| V-221097 | Low | The Cisco perimeter switch must be configured to have Cisco Discovery Protocol (CDP) disabled on all external interfaces. | CDP is a Cisco proprietary neighbor discovery protocol used to advertise device capabilities, configuration information, and device identity. CDP is media-and-protocol-independent as it runs over... |
| V-221096 | Low | The Cisco perimeter switch must be configured to have Link Layer Discovery Protocol (LLDP) disabled on all external interfaces. | LLDP is a neighbor discovery protocol used to advertise device capabilities, configuration information, and device identity. LLDP is media-and-protocol-independent as it runs over layer 2;... |
| V-221109 | Low | The Cisco BGP switch must be configured to reject route advertisements from CE switches with an originating AS in the AS_PATH attribute that does not belong to that customer. | Verifying the path a route has traversed will ensure that the local AS is not used as a transit network for unauthorized traffic. To ensure that the local AS does not carry any prefixes that do... |
| V-237754 | Low | The Cisco switch must be configured to advertise a hop limit of at least 32 in Switch Advertisement messages for IPv6 stateless auto-configuration deployments. | The Neighbor Discovery protocol allows a hop limit value to be advertised by routers in a Router Advertisement message being used by hosts instead of the standardized default value. If a very... |
| V-221146 | Low | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to limit the amount of source-active messages it accepts on a per-peer basis. | To reduce any risk of a denial-of-service (DoS) attack from a rogue or misconfigured MSDP switch, the switch must be configured to limit the number of source-active messages it accepts from each peer. |
| V-221101 | Low | The Cisco BGP switch must be configured to check whether a single-hop eBGP peer is directly connected. | As described in RFC 3682, GTSM is designed to protect a switch's IP-based control plane from DoS attacks. Many attacks focused on CPU load and line-card overload can be prevented by implementing... |
| V-221124 | Low | The Cisco PE switch must be configured to implement Internet Group Management Protocol (IGMP) or Multicast Listener Discovery (MLD) snooping for each Virtual Private LAN Services (VPLS) bridge domain. | IGMP snooping provides a way to constrain multicast traffic at Layer 2. By monitoring the IGMP membership reports sent by hosts within the bridge domain, the snooping application can set up Layer... |
| V-221108 | Low | The Cisco BGP switch must be configured to reject route advertisements from BGP peers that do not list their autonomous system (AS) number as the first AS in the AS_PATH attribute. | Verifying the path a route has traversed will ensure the IP core is not used as a transit network for unauthorized or possibly even internet traffic. All autonomous system boundary switches... |
| V-221147 | Low | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to use a loopback address as the source address when originating MSDP traffic. | Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of MSDP switches. It is easier to construct appropriate ingress filters... |
| V-221077 | Low | The Cisco switch must be configured to have all non-essential capabilities disabled. | A compromised switch introduces risk to the entire network infrastructure, as well as data resources that are accessible via the network. The perimeter defense has no oversight or control of... |
| V-221086 | Low | The Cisco switch must be configured to log all packets that have been dropped at interfaces via an ACL. | Auditing and logging are key components of any security architecture. It is essential for security personnel to know what is being done or attempted to be done, and by whom, to compile an accurate... |
| V-221083 | Low | The Cisco switch must be configured to have IP directed broadcast disabled on all interfaces. | An IP directed broadcast is a datagram sent to the broadcast address of a subnet that is not directly attached to the sending machine. The directed broadcast is routed through the network as a... |
| V-221111 | Low | The Cisco BGP switch must be configured to limit the prefix size on any inbound route advertisement to /24, or the least significant prefixes issued to the customer. | The effects of prefix de-aggregation can degrade switch performance due to the size of routing tables and also result in black-holing legitimate traffic. Initiated by an attacker or a... |
| V-221076 | Low | The Cisco switch must be configured to have all inactive layer 3 interfaces disabled. | An inactive interface is rarely monitored or controlled and may expose a network to an undetected attack on that interface. Unauthorized personnel with access to the communication facility could... |
| V-221144 | Low | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to filter received source-active multicast advertisements for any undesirable multicast groups and sources. | The interoperability of BGP extensions for interdomain multicast routing and MSDP enables seamless connectivity of multicast domains between autonomous systems. MP-BGP advertises the unicast... |
| V-221112 | Low | The Cisco BGP switch must be configured to use its loopback address as the source address for iBGP peering sessions. | Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of the BGP switches. It is easier to construct appropriate ingress... |
| V-221113 | Low | The Cisco MPLS switch must be configured to use its loopback address as the source address for LDP peering sessions. | Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of backbone switches. It is easier to construct appropriate ingress... |
| V-221145 | Low | The Cisco Multicast Source Discovery Protocol (MSDP) switch must be configured to filter source-active multicast advertisements to external MSDP peers to avoid global visibility of local-only multicast sources and groups. | To avoid global visibility of local information, there are a number of source-group (S, G) states in a PIM-SM domain that must not be leaked to another domain, such as multicast sources with... |
| V-221138 | Low | The Cisco multicast Designated switch (DR) must be configured to filter the Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Report messages to allow hosts to join only multicast groups that have been approved by the organization. | Real-time multicast traffic can entail multiple large flows of data. Large unicast flows tend to be fairly isolated (i.e., someone doing a file download here or there), whereas multicast can have... |
| V-221129 | Low | The Cisco PE switch must be configured to enforce a Quality-of-Service (QoS) policy to provide preferred treatment for mission-critical applications. | Different applications have unique requirements and toleration levels for delay, jitter, bandwidth, packet loss, and availability. To manage the multitude of applications and services, a network... |
| V-221114 | Low | The Cisco MPLS switch must be configured to synchronize Interior Gateway Protocol (IGP) and LDP to minimize packet loss when an IGP adjacency is established prior to LDP peers completing label exchange. | Packet loss can occur when an IGP adjacency is established and the switch begins forwarding packets using the new adjacency before the LDP label exchange completes between the peers on that link.... |
| V-221115 | Low | The MPLS switch with RSVP-TE enabled must be configured with message pacing to adjust maximum burst and maximum number of RSVP messages to an output queue based on the link speed and input queue size of adjacent core switches. | RSVP-TE can be used to perform constraint-based routing when building LSP tunnels within the network core that will support QoS and traffic engineering requirements. RSVP-TE is also used to enable... |
| V-221134 | Low | The Cisco multicast edge switch must be configured to establish boundaries for administratively scoped multicast traffic. | If multicast traffic is forwarded beyond the intended boundary, it is possible that it can be intercepted by unauthorized or unintended personnel.
Administrative scoped multicast addresses are... |
| V-221135 | Low | The Cisco multicast Rendezvous Point (RP) switch must be configured to limit the multicast forwarding cache so that its resources are not saturated by managing an overwhelming number of Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP) source-active entries. | MSDP peering between networks enables sharing of multicast source information. Enclaves with an existing multicast topology using PIM-SM can configure their RP switches to peer with MSDP switches.... |
| V-221136 | Low | The Cisco multicast Rendezvous Point (RP) switch must be configured to filter Protocol Independent Multicast (PIM) Register messages received from the Designated switch (DR) for any undesirable multicast groups and sources. | Real-time multicast traffic can entail multiple large flows of data. An attacker can flood a network segment with multicast packets, over-using the available bandwidth and thereby creating a... |
| V-221137 | Low | The Cisco multicast Rendezvous Point (RP) switch must be configured to filter Protocol Independent Multicast (PIM) Join messages received from the Designated Cisco switch (DR) for any undesirable multicast groups. | Real-time multicast traffic can entail multiple large flows of data. An attacker can flood a network segment with multicast packets, over-using the available bandwidth and thereby creating a... |
| V-221130 | Low | The Cisco P switch must be configured to enforce a Quality-of-Service (QoS) policy to provide preferred treatment for mission-critical applications. | Different applications have unique requirements and toleration levels for delay, jitter, bandwidth, packet loss, and availability. To manage the multitude of applications and services, a network... |
