Check: OL6-00-000092
Oracle Linux 6 STIG:
OL6-00-000092
(in versions v2 r7 through v1 r9)
Title
The system must not respond to ICMPv4 sent to a broadcast address. (Cat III impact)
Discussion
Ignoring ICMP echo requests (pings) sent to broadcast or multicast addresses makes the system slightly more difficult to enumerate on the network.
Check Content
The status of the "net.ipv4.icmp_echo_ignore_broadcasts" kernel parameter can be queried by running the following command: $ sysctl net.ipv4.icmp_echo_ignore_broadcasts The output of the command should indicate a value of "1". If this value is not the default value, investigate how it could have been adjusted at runtime, and verify it is not set improperly in "/etc/sysctl.conf". $ grep net.ipv4.icmp_echo_ignore_broadcasts /etc/sysctl.conf If the correct value is not returned, this is a finding.
Fix Text
To set the runtime status of the "net.ipv4.icmp_echo_ignore_broadcasts" kernel parameter, run the following command: # sysctl -w net.ipv4.icmp_echo_ignore_broadcasts=1 If this is not the system's default value, add the following line to "/etc/sysctl.conf": net.ipv4.icmp_echo_ignore_broadcasts = 1
Additional Identifiers
Rule ID: SV-208860r793645_rule
Vulnerability ID: V-208860
Group Title: SRG-OS-000480
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |