GEN003611 - The system must log martian packets - block in broadcast

Information

Martian packets are packets containing addresses known by the system to be invalid. Logging these messages allows the SA to identify misconfigurations or attacks in progress.

Solution

Configure the system to log martian packets using IPF. Add rules logging inbound traffic containing invalid source addresses, which minimally include the system's own addresses and broadcast addresses for attached subnets.

For example, consider a system with a single network connection having IP address 192.168.1.10 with a local subnet broadcast address of 192.168.1.255. Packets with source addresses of 192.168.1.10 and 192.168.1.255 must be logged if received by the system from the network connection.

Edit /etc/ipf/ipf.conf and add the following rules, substituting local addresses and interface names:
block in log quick on ce0 from 192.168.1.10 to any
block in log quick on ce0 from 192.168.1.255 to any

Reload the IPF rules.
Procedure:
# ipf -Fa -A -f /etc/ipf/ipf.conf

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_SOL_10_x86_V2R4_STIG.zip

Item Details

Category: AUDIT AND ACCOUNTABILITY

References: 800-53|AU-12a., CAT|III, CCI|CCI-000169, Rule-ID|SV-227804r603266_rule, STIG-ID|GEN003611, STIG-Legacy|SV-29773, STIG-Legacy|V-22418, Vuln-ID|V-227804

Plugin: Unix

Control ID: 60dc5e48d037a344aa094e63add3f14802d65e20fc9aa05dedc68732bb9c1a5e