Title

The pam_unix.so module must use a FIPS 140-2 approved cryptographic hashing algorithm for system authentication. (Cat II impact)

Discussion

Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised. Ubuntu operating systems utilizing encryption are required to use FIPS-compliant mechanisms for authenticating to cryptographic modules. FIPS 140-2 is the current standard for validating that mechanisms used to access cryptographic modules utilize authentication that meets DoD requirements. This allows for Security Levels 1, 2, 3, or 4 for use on a general purpose computing system.

Check Content

Verify that pam_unix.so auth is configured to use sha512. Check that pam_unix.so auth is configured to use sha512 with the following command: # grep password /etc/pam.d/common-password | grep pam_unix password [success=1 default=ignore] pam_unix.so obscure sha512 If "sha512" is not an option of the output, or is commented out, this is a finding.

Fix Text

Configure the Ubuntu operating system to use a FIPS 140-2 approved cryptographic hashing algorithm for system authentication. Edit/modify the following line in the file "/etc/pam.d/common-password" file to include the sha512 option for pam_unix.so: password [success=1 default=ignore] pam_unix.so obscure sha512 shadow remember=5

Additional Identifiers

Rule ID: SV-214957r610931_rule

Vulnerability ID: V-214957

Group Title: SRG-OS-000120-GPOS-00061

Expert Comments

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