Detections
Analytics
OL07-00-040640 - The Oracle Linux operating system must prevent Internet Protocol version 4 (IPv4) Internet Control Message Protocol (ICMP) redirect messages from being accepted.
Information
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.Solution
Set the system to not accept IPv4 ICMP redirect messages 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.default.accept_redirects = 0
Issue the following command to make the changes take effect:
# sysctl --system
See Also
https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Oracle_Linux_7_V3R5_STIG.zip
Item Details
Audit Name: DISA Oracle Linux 7 STIG v3r5
Category: CONFIGURATION MANAGEMENT
References: 800-53|CM-6b., CAT|II, CCI|CCI-000366, Rule-ID|SV-221878r991589_rule, STIG-ID|OL07-00-040640, STIG-Legacy|SV-108599, STIG-Legacy|V-99495, Vuln-ID|V-221878
Plugin: Unix
Control ID: fd84ec7accb549ad727553b7cd9a0e07117beb23d1cdef5006f16bcc00f202b9