Detections
Analytics

1.415 RHEL-10-800140

Information

RHEL 10 must prevent Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages from being accepted.

GROUP ID: V-281346RULE ID: SV-281346r1197251

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.

This feature of the IPv4 protocol has few legitimate uses. It must be disabled unless absolutely required.

Satisfies: SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00077

Solution

Configure RHEL 10 to prevent IPv4 ICMP redirect messages from being accepted.

Create a configuration file if it does not already exist:

$ sudo vi /etc/sysctl.d/99-ipv4_accept_redirects.conf

Add the following line to the file:

net.ipv4.conf.default.accept_redirects = 0

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

$ sudo sysctl --system

See Also

https://workbench.cisecurity.org/benchmarks/26403

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-5, 800-53|SC-7(3), CAT|II, CCI|CCI-001101, CCI|CCI-002385, Rule-ID|SV-281346r1197251_rule, STIG-ID|RHEL-10-800140, Vuln-ID|V-281346

Plugin: Unix

Control ID: 1ae2e2f029b91fce096b94aa69c4db55d6e1e8a52bf3926ef8601519b84cf439