CISC-RT-000180 - The Cisco router must be configured to have Internet Control Message Protocol (ICMP) mask reply messages disabled on all external interfaces.

Information

The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Routers automatically send ICMP messages under a wide variety of conditions. Mask Reply ICMP messages are commonly used by attackers for network mapping and diagnosis.

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

Solution

Disable ip mask-reply on all external interfaces as shown below.

R4(config)#int g0/1
R4(config-if)#no ip mask-reply

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS_Router_Y22M07_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-5, CAT|II, CCI|CCI-002385, Rule-ID|SV-216566r531085_rule, STIG-ID|CISC-RT-000180, STIG-Legacy|SV-105671, STIG-Legacy|V-96533, Vuln-ID|V-216566

Plugin: Cisco

Control ID: 264e086b0db71b16b985c7443b41c050b6d64bf43e1855c45b81cd266e4822bd