The SUSE operating system must not allow interfaces to accept Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages by default.
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 modify the host's route table and are unauthenticated. An illicit ICMP redirect message could result in a man-in-the-middle attack.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-217292r991589_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Configure the SUSE operating system ignores IPv4 ICMP redirect messages by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value):
net.ipv4.conf.default.accept_redirects = 0
Run the following command to apply this value: