RHEL 10 must ensure that the pam_unix.so module is configured in the password-auth file to use a FIPS 140-3-approved cryptographic hashing algorithm for system authentication.

Unapproved mechanisms that are used for authentication to the cryptographic module are not verified; therefore, they cannot be relied on to provide confidentiality or integrity, and DOD data may be compromised. RHEL 10 systems using encryption are required to use FIPS-compliant mechanisms for authenticating to cryptographic modules. FIPS 140-3 is the current standard for validating that mechanisms used to access cryptographic modules use authentication that meets DOD requirements. This allows for Security Levels 1, 2, 3, or 4 for use on a general-purpose computing system. Satisfies: SRG-OS-000073-GPOS-00041, SRG-OS-000120-GPOS-00061

Verify RHEL 10 configures the pam_unix.so module to use sha512 in "/etc/pam.d/password-auth" with the following command: $ sudo grep "^password.*pam_unix.so.*sha512" /etc/pam.d/password-auth password sufficient pam_unix.so sha512 If "sha512" is missing, or the line is commented out, this is a finding.

Configure RHEL 10 to use the sha512 cryptographic hashing algorithm for local account passwords. Edit/modify the following line in the "/etc/pam.d/password-auth" file to include the sha512 option for pam_unix.so: password sufficient pam_unix.so sha512