Detections
Analytics

1.434 OL09-00-006030

Information

OL 9 must not respond to Internet Control Message Protocol (ICMP) echoes sent to a broadcast address.

GROUP ID: V-271873
RULE ID: SV-271873r1092331

Responding to broadcast (ICMP) echoes facilitates network mapping and provides a vector for amplification attacks.

Ignoring ICMP echo requests (pings) sent to broadcast or multicast addresses makes the system slightly more difficult to enumerate on the network.

Solution

Configure OL 9 to not respond to IPv4 ICMP echoes sent to a broadcast address.

Add or edit the following line in a single system configuration file in the "/etc/sysctl.d/" directory:

net.ipv4.icmp_echo_ignore_broadcasts = 1

Load settings from all system configuration files with the following command:

$ sudo sysctl --system

See Also

https://workbench.cisecurity.org/benchmarks/27024

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b., CCI|CCI-000366, Rule-ID|SV-271873r1092331_rule, STIG-ID|OL09-00-006030, Vuln-ID|V-271873

Plugin: Unix

Control ID: a13e97b04080729b050c2d1848090523288b283e83edee0460c29f6de7cc8f45