CISC-RT-000250 - 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

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 introduce any unacceptable risk to the network infrastructure or data. An example of a flow control restriction is blocking outside traffic claiming to be from within the organization. For most switches, internal information flow control is a product of system design.

NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.

Solution

Step 1: Configure an ACL to allow or deny traffic as shown in the example below:

SW2(config)# ip access-list EXTERNAL_ACL
SW2(config-acl)# permit tcp any any established
SW2(config-acl)# permit tcp x.11.1.1/32 eq bgp x.11.1.2/32
SW2(config-acl)# permit tcp x.11.1.1/32 x.11.1.2/32 eq bgp
SW2(config-acl)# permit icmp x.11.1.1/32 x.11.1.2/32 echo
SW2(config-acl)# permit icmp x.11.1.1/32 x.11.1.2/32 echo-reply
SW2(config-acl)# permit tcp any x.11.2.3/32 eq www
SW2(config-acl)# deny ip any any log
SW2(config-acl)# exit

Step 2: Apply the ACL inbound on all applicable interfaces.

SW1(config)#int e2/2
SW1(config-if)# ip access-group EXTERNAL_ACL in

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_NX-OS_Switch_Y21M10_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-4, CAT|II, CCI|CCI-001414, Rule-ID|SV-221088r622190_rule, STIG-ID|CISC-RT-000250, STIG-Legacy|SV-110995, STIG-Legacy|V-101891, Vuln-ID|V-221088

Plugin: Cisco

Control ID: 4db5a4fad5ef2055eea41422128c82662578665e9f74cb4a73a088629130f90e