{"description": " To properly set the permissions of <code>/etc/ssh/*.pub</code>, run the command: <pre>$ sudo chmod 0644 /etc/ssh/*.pub</pre>", "rationale": "If a public host key file is modified by an unauthorized user, the SSH service\nmay be compromised.", "severity": "medium", "references": {"cis-csc": ["12", "13", "14", "15", "16", "18", "3", "5"], "cobit5": ["APO01.06", "DSS05.04", "DSS05.07", "DSS06.02"], "cui": ["3.1.13", "3.13.10"], "isa-62443-2009": ["4.3.3.7.3"], "isa-62443-2013": ["SR 2.1", "SR 5.2"], "iso27001-2013": ["A.10.1.1", "A.11.1.4", "A.11.1.5", "A.11.2.1", "A.13.1.1", "A.13.1.3", "A.13.2.1", "A.13.2.3", "A.13.2.4", "A.14.1.2", "A.14.1.3", "A.6.1.2", "A.7.1.1", "A.7.1.2", "A.7.3.1", "A.8.2.2", "A.8.2.3", "A.9.1.1", "A.9.1.2", "A.9.2.3", "A.9.4.1", "A.9.4.4", "A.9.4.5"], "nerc-cip": ["CIP-003-8 R5.1.1", "CIP-003-8 R5.3", "CIP-004-6 R2.3", "CIP-007-3 R2.1", "CIP-007-3 R2.2", "CIP-007-3 R2.3", "CIP-007-3 R5.1", "CIP-007-3 R5.1.1", "CIP-007-3 R5.1.2"], "nist": ["AC-17(a)", "CM-6(a)", "AC-6(1)"], "nist-csf": ["PR.AC-4", "PR.DS-5"], "pcidss": ["Req-2.2.4"], "srg": ["SRG-OS-000480-GPOS-00227"], "anssi": ["R50"], "cis": ["5.1.3"], "pcidss4": ["2.2.6", "2.2"]}, "control_references": {"anssi": ["R50"], "cis": ["5.1.3"], "pcidss4": ["2.2.6", "2.2"]}, "components": [], "identifiers": {}, "ocil_clause": "/etc/ssh/*.pub does not have unix mode -rw-r--r--", "ocil": "To check the permissions of <code>/etc/ssh/*.pub</code>,\nrun the command:\n<pre>$ ls -l /etc/ssh/*.pub</pre>\nIf properly configured, the output should indicate the following permissions:\n<code>-rw-r--r--</code>", "oval_external_content": null, "fixtext": " Configure the \"/etc/ssh/*_key.pub\" file to \"0600\" by running the following command:\n$ sudo chmod 0600 /etc/ssh/*_key.pub", "checktext": "", "vuldiscussion": "", "srg_requirement": "The Ubuntu 22.04 SSH public host key files must have mode 0644 or less permissive.", "warnings": [{"general": "Remediation is not possible at bootable container build time because SSH host\nkeys are generated post-deployment."}], "conflicts": [], "requires": [], "policy_specific_content": {"stig": {"srg_requirement": "Ubuntu 22.04 SSH public host key files must have mode 0644 or less permissive.", "vuldiscussion": "If a public host key file is modified by an unauthorized user, the SSH service may be compromised.", "checktext": "Verify the SSH public host key files have a mode of \"0644\" or less permissive with the following command:\n\nNote: SSH public key files may be found in other directories on the system depending on the installation.\n\n$ sudo stat -c \"%a %n\" /etc/ssh/*.pub\n\n644 /etc/ssh/ssh_host_dsa_key.pub\n644 /etc/ssh/ssh_host_ecdsa_key.pub\n644 /etc/ssh/ssh_host_ed25519_key.pub\n644 /etc/ssh/ssh_host_rsa_key.pub\n\nIf any key.pub file has a mode more permissive than \"0644\", this is a finding.", "fixtext": "Change the mode of public host key files under \"/etc/ssh\" to \"0644\" with the following command:\n\n$ sudo chmod 0644 /etc/ssh/*key.pub\n\nRestart the SSH daemon for the changes to take effect:\n\n$ sudo systemctl restart sshd.service"}}, "platform": "system_with_kernel", "platforms": ["system_with_kernel"], "sce_metadata": {}, "inherited_platforms": [], "cpe_platform_names": ["system_with_kernel"], "inherited_cpe_platform_names": [], "bash_conditional": null, "fixes": {}, "title": "Verify Permissions on SSH Server Public *.pub Key Files", "definition_location": "/aptdata/openscap/scap-security-guide/linux_os/guide/services/ssh/file_permissions_sshd_pub_key/rule.yml", "template": {"name": "file_permissions", "vars": {"filepath": "/etc/ssh/", "file_regex": "^.*\\.pub$", "filemode": "0644"}, "backends": {}}}