{"description": "To set the runtime status of the <code>net.ipv6.conf.default.accept_ra</code> kernel parameter, run the following command: <pre>$ sudo sysctl -w net.ipv6.conf.default.accept_ra=0</pre>\nTo make sure that the setting is persistent, add the following line to a file in the directory <tt>/etc/sysctl.d</tt>: <pre>net.ipv6.conf.default.accept_ra = 0</pre>", "rationale": "An illicit router advertisement message could result in a man-in-the-middle attack.", "severity": "medium", "references": {"cis-csc": ["11", "14", "3", "9"], "cobit5": ["BAI10.01", "BAI10.02", "BAI10.03", "BAI10.05", "DSS05.02", "DSS05.05", "DSS06.06"], "cui": ["3.1.20"], "isa-62443-2009": ["4.3.3.5.1", "4.3.3.5.2", "4.3.3.5.3", "4.3.3.5.4", "4.3.3.5.5", "4.3.3.5.6", "4.3.3.5.7", "4.3.3.5.8", "4.3.3.6.1", "4.3.3.6.2", "4.3.3.6.3", "4.3.3.6.4", "4.3.3.6.5", "4.3.3.6.6", "4.3.3.6.7", "4.3.3.6.8", "4.3.3.6.9", "4.3.3.7.1", "4.3.3.7.2", "4.3.3.7.3", "4.3.3.7.4", "4.3.4.3.2", "4.3.4.3.3"], "isa-62443-2013": ["SR 1.1", "SR 1.10", "SR 1.11", "SR 1.12", "SR 1.13", "SR 1.2", "SR 1.3", "SR 1.4", "SR 1.5", "SR 1.6", "SR 1.7", "SR 1.8", "SR 1.9", "SR 2.1", "SR 2.2", "SR 2.3", "SR 2.4", "SR 2.5", "SR 2.6", "SR 2.7", "SR 7.6"], "iso27001-2013": ["A.12.1.2", "A.12.5.1", "A.12.6.2", "A.14.2.2", "A.14.2.3", "A.14.2.4", "A.9.1.2"], "nist": ["CM-7(a)", "CM-7(b)", "CM-6(a)"], "nist-csf": ["PR.IP-1", "PR.PT-3"], "srg": ["SRG-OS-000480-GPOS-00227"], "cis": ["3.3.11"]}, "control_references": {"cis": ["3.3.11"]}, "components": [], "identifiers": {}, "ocil_clause": "the correct value is not returned", "ocil": "The runtime status of the <code>net.ipv6.conf.default.accept_ra</code> kernel parameter can be queried\nby running the following command:\n<pre>$ sysctl net.ipv6.conf.default.accept_ra</pre>\n<code>0</code>.\n", "oval_external_content": null, "fixtext": "Configure Ubuntu 22.04 to not accept router advertisements on all IPv6 interfaces by default unless the system is a router.\nAdd or edit the following line in a system configuration file in the \"/etc/sysctl.d/\" directory:\nnet.ipv6.conf.default.accept_ra = 0\n\nLoad settings from all system configuration files with the following command:\n\n$ sudo sysctl --system", "checktext": "", "vuldiscussion": "", "srg_requirement": "Ubuntu 22.04 must not accept router advertisements on all IPv6 interfaces by default.", "warnings": [], "conflicts": [], "requires": [], "policy_specific_content": {"stig": {"srg_requirement": "Ubuntu 22.04 must not accept router advertisements on all IPv6 interfaces by default.", "vuldiscussion": "An illicit router advertisement message could result in a man-in-the-middle attack.", "checktext": "Verify Ubuntu 22.04 does not accept router advertisements on all IPv6 interfaces by default, unless the system is a router.\n\nNote: If IPv6 is disabled on the system, this requirement is Not Applicable.\n\nDetermine if router advertisements are not accepted by default by using the following command:\n\n$ sudo sysctl net.ipv6.conf.default.accept_ra\n\nnet.ipv6.conf.default.accept_ra = 0\n\nIf the \"accept_ra\" value is not \"0\" and is not documented with the information system security officer (ISSO) as an operational requirement, this is a finding.\n\nCheck that the configuration files are present to enable this network parameter.\n\n$ sudo /usr/lib/systemd/systemd-sysctl --cat-config | egrep -v '^(#|;)' |  grep -F net.ipv6.conf.default.accept_ra | tail -1\n\nnet.ipv6.conf.default.accept_ra = 0\n\nIf \"net.ipv6.conf.default.accept_ra\" is not set to \"0\" or is missing, this is a finding.", "fixtext": "Configure Ubuntu 22.04 to not accept router advertisements on all IPv6 interfaces by default unless the system is a router.\n\nAdd or edit the following line in a single system configuration file, in the \"/etc/sysctl.d/\" directory:\n\nnet.ipv6.conf.default.accept_ra = 0\n\nLoad settings from all system configuration files with the following command:\n\n$ sudo sysctl --system"}}, "platform": "system_with_kernel", "platforms": ["system_with_kernel"], "sce_metadata": {"check-import": "stdout", "check-export": ["sysctl_net_ipv6_conf_default_accept_ra_value=xccdf_org.ssgproject.content_value_sysctl_net_ipv6_conf_default_accept_ra_value"], "platform": ["multi_platform_all"], "environment": "any", "filename": "sysctl_net_ipv6_conf_default_accept_ra.sh", "relative_path": "ubuntu2204/checks/sce/sysctl_net_ipv6_conf_default_accept_ra.sh"}, "inherited_platforms": ["ipv6[enabled]"], "cpe_platform_names": ["system_with_kernel"], "inherited_cpe_platform_names": ["ipv6_enabled"], "bash_conditional": null, "fixes": {}, "title": "Disable Accepting Router Advertisements on all IPv6 Interfaces by Default", "definition_location": "/aptdata/openscap/scap-security-guide/linux_os/guide/system/network/network-ipv6/configuring_ipv6/sysctl_net_ipv6_conf_default_accept_ra/rule.yml", "template": {"name": "sysctl", "vars": {"sysctlvar": "net.ipv6.conf.default.accept_ra", "datatype": "int"}, "backends": {}}}