The macOS system must limit SSH to FIPS-compliant connections.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-259439APPL-14-000057SV-259439r958408_ruleCCI-000068high
Description
SSH must be configured to limit the Ciphers, HostbasedAcceptedAlgorithms, HostKeyAlgorithms, KexAlgorithms, MACs, PubkeyAcceptedAlgorithms, CASignatureAlgorithms to algorithms that are FIPS 140 validated. FIPS 140-2 is the current standard for validating that mechanisms used to access cryptographic modules utilize authentication that meet federal requirements. Operating systems utilizing encryption must use FIPS-validated mechanisms for authenticating to cryptographic modules. Note: For more information on FIPS compliance with the version of SSH included in the macOS, the manual page apple_ssh_and_fips has additional information. Satisfies: SRG-OS-000033-GPOS-00014,SRG-OS-000120-GPOS-00061,SRG-OS-000250-GPOS-00093,SRG-OS-000396-GPOS-00176,SRG-OS-000424-GPOS-00188,SRG-OS-000478-GPOS-00223
STIGDate
Apple macOS 14 (Sonoma) Security Technical Implementation Guide2024-12-04

Details

Check Text (C-259439r958408_chk)

Verify the macOS system is configured to limit SSH to FIPS-compliant connections with the following command: fips_ssh_config="Host * Ciphers aes128-gcm@openssh.com HostbasedAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com HostKeyAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com KexAlgorithms ecdh-sha2-nistp256 MACs hmac-sha2-256 PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com CASignatureAlgorithms ecdsa-sha2-nistp256" /usr/bin/grep -c "$fips_ssh_config" /etc/ssh/ssh_config.d/fips_ssh_config If the result is not "8", this is a finding.

Fix Text (F-63086r945376_fix)

Configure the macOS system to limit SSH to FIPS-compliant connections with the following command: fips_ssh_config="Host * Ciphers aes128-gcm@openssh.com HostbasedAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com HostKeyAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com KexAlgorithms ecdh-sha2-nistp256 MACs hmac-sha2-256 PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,ecdsa-sha2-nistp256-cert-v01@openssh.com CASignatureAlgorithms ecdsa-sha2-nistp256" /bin/echo "${fips_ssh_config}" > /etc/ssh/ssh_config.d/fips_ssh_config