Detections
Analytics
CISC-RT-000394 - The Cisco perimeter router must be configured to drop IPv6 packets containing a Hop-by-Hop header with invalid option type values.
Information
These options are intended to be for the Destination Options header only. The optional and extensible natures of the IPv6 extension headers require higher scrutiny since many implementations do not always drop packets with headers that it cannot recognize and hence could cause a Denial-of-Service on the target device. In addition, the type, length, value (TLV) formatting provides the ability for headers to be very large.NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.
Solution
Drop IPv6 packets containing a Hop-by-Hop header as shown in the example below.R1(config)#ipv6 access-list FILTER_IPV6
R1(config-ipv6-acl)#deny hbh any any dest-option log
R1(config-ipv6-acl)# permit ipv6 ...
...
...
...
R1(config-ipv6-acl)#deny ipv6 any any log
R1(config-ipv6-acl)#exit
R1(config)#int g1/0
R1(config-if)#ipv6 traffic-filter FILTER_IPV6
R1(config-if)#end
See Also
https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS_Router_Y26M01_STIG.zip
Item Details
Audit Name: DISA Cisco IOS Router RTR STIG v3r4
Category: SYSTEM AND COMMUNICATIONS PROTECTION
References: 800-53|SC-7(11), CAT|II, CCI|CCI-002403, Rule-ID|SV-230145r1132551_rule, STIG-ID|CISC-RT-000394, Vuln-ID|V-230145
Plugin: Cisco
Control ID: 7bdb45100e35913fcf28551a63ea7aaba2ec3f10606df3e6ac4076d57a8e4a48