{"description": "This feature reduces the number of hardware side channels by ensuring that the majority of\nkernel addresses are not mapped into userspace.\nThis configuration is available from kernel 4.15, but may be available if backported\nby distros.\n\nThe configuration that was used to build kernel is available at <tt>/boot/config-*</tt>.\n    To check the configuration value for <tt>CONFIG_PAGE_TABLE_ISOLATION</tt>, run the following command:\n    <tt>grep CONFIG_PAGE_TABLE_ISOLATION /boot/config-*</tt>\n    \n    For each kernel installed, a line with value \"y\" should be returned.\n    ", "rationale": "This is a countermeasure to the Meltdown attack.", "severity": "high", "references": {"anssi": ["R25"]}, "control_references": {"anssi": ["R25"]}, "components": [], "identifiers": {}, "ocil_clause": "the kernel was not built with the required value", "ocil": "To determine the config value the kernel was built with, run the following command:\n    <pre>$ grep CONFIG_PAGE_TABLE_ISOLATION /boot/config.*</pre>\n    \n    For each kernel installed, a line with value \"y\" should be returned.\n    ", "oval_external_content": null, "fixtext": "", "checktext": "", "vuldiscussion": "", "srg_requirement": "", "warnings": [{"general": "There is no remediation for this besides re-compiling the kernel with the appropriate value for the config."}], "conflicts": [], "requires": [], "policy_specific_content": {}, "platform": "x86_64_arch", "platforms": ["x86_64_arch"], "sce_metadata": {}, "inherited_platforms": ["system_with_kernel"], "cpe_platform_names": ["x86_64_arch"], "inherited_cpe_platform_names": ["system_with_kernel"], "bash_conditional": null, "fixes": {}, "title": "Remove the kernel mapping in user mode", "definition_location": "/aptdata/openscap/scap-security-guide/linux_os/guide/system/kernel_build_config/kernel_config_page_table_isolation/rule.yml", "template": {"name": "kernel_build_config", "vars": {"config": "CONFIG_PAGE_TABLE_ISOLATION", "value": "y"}, "backends": {}}}