The Oracle Linux operating system must not send Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirects.
An XCCDF Rule
Description
<VulnDiscussion>ICMP redirect messages are used by routers to inform hosts that a more direct route exists for a particular destination. These messages contain information from the system's route table, possibly revealing portions of the network topology.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-221881r991589_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Configure the system not to allow interfaces to perform IPv4 ICMP redirects.
Set the system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" or a configuration file in the /etc/sysctl.d/ directory (or modify the line to have the required value):
net.ipv4.conf.all.send_redirects = 0