Title

RHEL 8 must map the authenticated identity to the user or group account for PKI-based authentication. (Cat II impact)

Discussion

Without mapping the certificate used to authenticate to the user account, the ability to determine the identity of the individual user or group will not be available for forensic analysis. There are various methods of mapping certificates to user/group accounts for RHEL 8. For the purposes of this requirement, the check and fix will account for Active Directory mapping. Some of the other possible methods include joining the system to a domain and utilizing a Red Hat idM server, or a local system mapping, where the system is not part of a domain.

Check Content

Verify the certificate of the user or group is mapped to the corresponding user or group in the "sssd.conf" file with the following command: Note: If the System Administrator demonstrates the use of an approved alternate multifactor authentication method, this requirement is not applicable. $ sudo cat /etc/sssd/sssd.conf [sssd] config_file_version = 2 services = pam, sudo, ssh domains = testing.test [pam] pam_cert_auth = True [domain/testing.test] id_provider = ldap [certmap/testing.test/rule_name] matchrule =<SAN>.*EDIPI@mil maprule = (userCertificate;binary={cert!bin}) domains = testing.test If the certmap section does not exist, ask the System Administrator to indicate how certificates are mapped to accounts. If there is no evidence of certificate mapping, this is a finding.

Fix Text

Configure the operating system to map the authenticated identity to the user or group account by adding or modifying the certmap section of the "/etc/sssd/sssd.conf file based on the following example: [certmap/testing.test/rule_name] matchrule =<SAN>.*EDIPI@mil maprule = (userCertificate;binary={cert!bin}) domains = testing.test The "sssd" service must be restarted for the changes to take effect. To restart the "sssd" service, run the following command: $ sudo systemctl restart sssd.service

Additional Identifiers

Rule ID: SV-230355r858743_rule

Vulnerability ID: V-230355

Group Title: SRG-OS-000068-GPOS-00036

Expert Comments

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