Check: RHEL-09-611170
RHEL 9 STIG:
RHEL-09-611170
(in version v2 r3)
Title
RHEL 9 must implement certificate status checking for multifactor authentication. (Cat II impact)
Discussion
Using an authentication device, such as a DOD 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 DOD 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
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 operating system implements Online Certificate Status Protocol (OCSP) and is using the proper digest value on the system with the following command: $ sudo grep -ir certificate_verification /etc/sssd/sssd.conf /etc/sssd/conf.d/ | grep -v "^#" 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.
Fix Text
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
Additional Identifiers
Rule ID: SV-258123r1045248_rule
Vulnerability ID: V-258123
Group Title: SRG-OS-000375-GPOS-00160
Expert Comments
CCIs
| Number | Definition |
|---|---|
| CCI-001948 |
The information system implements multifactor authentication for remote access to privileged accounts such that one of the factors is provided by a device separate from the system gaining access. |
| CCI-001954 |
Electronically verify Personal Identity Verification-compliant credentials. |
| CCI-004046 |
Implement multi-factor authentication for local; network; and/or remote access to privileged accounts; and/or non-privileged accounts such that one of the factors is provided by a device separate from the system gaining access. |