RHEL-09-254030 - RHEL 9 must not accept router advertisements on all IPv6 interfaces by default.

Information

An illicit router advertisement message could result in a man-in-the-middle attack.

Solution

Configure RHEL 9 to not accept router advertisements on all IPv6 interfaces by default unless the system is a router.

Add or edit the following line in a single system configuration file, in the '/etc/sysctl.d/' directory:

net.ipv6.conf.default.accept_ra = 0

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

$ sudo sysctl --system

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_RHEL_9_V2R2_STIG.zip

Item Details

Category: CONFIGURATION MANAGEMENT

References: 800-53|CM-6b., CAT|II, CCI|CCI-000366, Rule-ID|SV-257975r991589_rule, STIG-ID|RHEL-09-254030, Vuln-ID|V-257975

Plugin: Unix

Control ID: 583e1df1c86969234e6c782eba9e1847e4e84b2f67f4a5b7ced50faf4efbcc5b