Title

Amazon Linux 2023 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.

Check Content

Note: If the system administrator (SA) demonstrates the use of an approved alternate multifactor authentication method, this requirement is not applicable. 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: $ sudo find /etc/sssd/sssd.conf /etc/sssd/conf.d/ -type f -exec cat {} \; [sssd] config_file_version = 2 services = pam, sudo, ssh domains = testing.test [pam] pam_cert_auth = True offline_credentials_expiration = 1 [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 SA to indicate how certificates are mapped to accounts. If there is no evidence of certificate mapping, this is a finding.

Fix Text

Configure Amazon Linux 2023 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-274060r1120168_rule

Vulnerability ID: V-274060

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

Expert Comments

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