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RHEL-09-611170 RHEL 9 must implement certificate status checking for multifactor authentication.

DISA STIG library V2R10
All changes in this version
first version loaded CAT II

Maps to IA-2(6), IA-2(11), IA-2(12) via CCI-004046, CCI-001954, CCI-001948

Title

RHEL 9 must implement certificate status checking for multifactor authentication.

Control

Note: If the system administrator (SA) demonstrates the use of an approved alternate multifactor authentication method, this requirement is not applicable. Verify the operating system implements Online Certificate Status Protocol (OCSP) and is using the proper digest value on the system with the following command: $ sudo grep -sir certificate_verification /etc/sssd/sssd.conf /etc/sssd/conf.d/ | grep -v "^#" /etc/sssd/conf.d/certificate_verification:certificate_verification = ocsp_dgst=sha512 If the certificate_verification line is missing from the [sssd] section, or is missing "ocsp_dgst=sha512", ask the administrator to indicate what type of multifactor authentication is being used and how the system implements certificate status checking. If there is no evidence of certificate status checking being used, this is a finding.

Discussion

Using an authentication device, such as a DoW common access card (CAC) or token that is separate from the information system, ensures that even if the information system is compromised, credentials stored on the authentication device will not be affected. Multifactor solutions that require devices separate from information systems gaining access include, for example, hardware tokens providing time-based or challenge-response authenticators and smart cards such as the U.S. Government Personal Identity Verification (PIV) card and the DoW CAC. RHEL 9 includes multiple options for configuring certificate status checking, but for this requirement focuses on the System Security Services Daemon (SSSD). By default, SSSD performs Online Certificate Status Protocol (OCSP) checking and certificate verification using a sha256 digest function. Satisfies: SRG-OS-000375-GPOS-00160, SRG-OS-000377-GPOS-00162

Related controls

CCI-001948, CCI-001954, CCI-004046

Fix

Configure RHEL 9 to implement certificate status checking for multifactor authentication. Review the "/etc/sssd/conf.d/certificate_verification.conf" file to determine if the system is configured to prevent OCSP or certificate verification. Add the following line to the "/etc/sssd/conf.d/certificate_verification.conf" file: certificate_verification = ocsp_dgst=sha512 Set the correct ownership and permissions on the "/etc/sssd/conf.d/certificate_verification.conf" file by running these commands: $ sudo chown root:root "/etc/sssd/conf.d/certificate_verification.conf" $ sudo chmod 600 "/etc/sssd/conf.d/certificate_verification.conf" 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