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V-281350

CAT II (Medium)

RHEL 10 must limit the number of bogus Internet Control Message Protocol (ICMP) response errors logs.

Rule ID

SV-281350r1167200_rule

STIG

Red Hat Enterprise Linux 10 Security Technical Implementation Guide

Version

V1R1

CCIs

CCI-002385 CCI-001105

Discussion

Some routers will send responses to broadcast frames that violate RFC-1122, which fills up a log file system with many useless error messages. An attacker may take advantage of this and attempt to flood the logs with bogus error logs. Ignoring bogus ICMP error responses reduces log size, although some activity would not be logged. Satisfies: SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00081

Check Content

Verify RHEL 10 limits the number of bogus ICMP response errors logs.

Check the value of the "net.ipv4.icmp_ignore_bogus_error_response" variables with the following command:

$ sudo sysctl net.ipv4.icmp_ignore_bogus_error_responses
net.ipv4.icmp_ignore_bogus_error_responses = 1

If "net.ipv4.icmp_ignore_bogus_error_response" is not set to "1" or is missing, this is a finding.

Fix Text

Configure RHEL 10 to not log bogus ICMP errors.

Create a configuration file if it does not already exist:

$ sudo vi /etc/sysctl.d/ipv4_icmp_ignore_bogus_error_responses.conf

Add the following line to the file:

net.ipv4.icmp_ignore_bogus_error_responses = 1

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

$ sudo sysctl --system