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.

STIG ID: RHEL-10-600650  |  SRG: SRG-OS-000073-GPOS-00041 |  Severity: medium (CAT II)  |  CCI: CCI-004062,CCI-000803 |  Vulnerability Id: V-281217

Vulnerability Discussion

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

Check

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.

Fix

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