The Photon operating system must not respond to IPv4 Internet Control Message Protocol (ICMP) echoes sent to a broadcast address.
Severity | Group ID | Group Title | Version | Rule ID | Date | STIG Version |
|---|---|---|---|---|---|---|
| medium | V-258887 | SRG-OS-000480-GPOS-00227 | PHTN-40-000224 | SV-258887r991589_rule | 2024-07-11 | 2 |
| Description |
|---|
| Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks. |
| ℹ️ Check |
|---|
| At the command line, run the following command to verify ICMP echoes sent to a broadcast address are ignored: # /sbin/sysctl net.ipv4.icmp_echo_ignore_broadcasts Example result: net.ipv4.icmp_echo_ignore_broadcasts = 1 If the "net.ipv4.icmp_echo_ignore_broadcasts" kernel parameter is not set to "1", this is a finding. |
| ✔️ Fix |
|---|
| Navigate to and open: /etc/sysctl.d/zz-stig-hardening.conf Add or update the following line: net.ipv4.icmp_echo_ignore_broadcasts = 1 At the command line, run the following command to load the new configuration: # /sbin/sysctl --load /etc/sysctl.d/zz-stig-hardening.conf Note: If the file zz-stig-hardening.conf does not exist, it must be created. |