RHEL-07-040620 - The Red Hat Enterprise Linux operating system must not forward Internet Protocol version 4 (IPv4) source-routed packets by default.

Information

Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routed traffic, such as when IPv4 forwarding is enabled and the system is functioning as a router.

Solution

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.default.accept_source_route = 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_RHEL_7_V3R15_STIG.zip

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b., CAT|II, CCI|CCI-000366, Rule-ID|SV-204612r991589_rule, STIG-ID|RHEL-07-040620, STIG-Legacy|SV-86909, STIG-Legacy|V-72285, Vuln-ID|V-204612

Plugin: Unix

Control ID: fb18429e0374f08c52178773315529df901199d4d354e015495b4710527fe643