macOS APPL-26-000057

Verify the macOS system is configured to limit SSH to FIPS-compliant connections with the following command: fips_ssh_config=("Ciphers [email protected]" "HostbasedAcceptedAlgorithms ecdsa-sha2-nistp256,[email protected]" "HostKeyAlgorithms [email protected],[email protected],ecdsa-sha2-nistp256,[email protected]" "KexAlgorithms ecdh-sha2-nistp256" "MACs [email protected],hmac-sha2-256" "PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,[email protected],[email protected]" "CASignatureAlgorithms ecdsa-sha2-nistp256,[email protected]") total=0 ret="pass" for config in $fips_ssh_config; do if [[ "$ret" == "fail" ]]; then break fi for u in $(/usr/bin/dscl . list /users shell | /usr/bin/egrep -v '(^_)|(root)|(/usr/bin/false)' | /usr/bin/awk '{print $1}'); do sshCheck=$(/usr/bin/sudo -u $u /usr/bin/ssh -G . | /usr/bin/grep -ci "$config") if [[ "$sshCheck" == "0" ]]; then ret="fail" break fi done done echo $ret If the result is not "pass", this is a finding.

Configure the macOS system to limit SSH to FIPS-compliant connections with the following command: if [ -f /etc/ssh/crypto.conf ] && /usr/bin/grep -q "Include /etc/ssh/crypto.conf" /etc/ssh/ssh_config.d/100-macos.conf 2>/dev/null; then /bin/ln -fs /etc/ssh/crypto/fips.conf /etc/ssh/crypto.conf fi include_dir=$(/usr/bin/awk '/^Include/ {print $2}' /etc/ssh/ssh_config | /usr/bin/tr -d '*') fips_ssh_config=("Ciphers [email protected]" "HostbasedAcceptedAlgorithms ecdsa-sha2-nistp256,[email protected]" "HostKeyAlgorithms [email protected],[email protected],ecdsa-sha2-nistp256,[email protected]" "KexAlgorithms ecdh-sha2-nistp256" "MACs [email protected],hmac-sha2-256" "PubkeyAcceptedAlgorithms ecdsa-sha2-nistp256,[email protected],[email protected]" "CASignatureAlgorithms ecdsa-sha2-nistp256,[email protected]") for ssh_config in $fips_ssh_config; do ssh_setting=$(echo $ssh_config | /usr/bin/cut -d " " -f1) /usr/bin/grep -qEi "^$ssh_setting" "${include_dir}01-mscp-ssh.conf" && /usr/bin/sed -i "" "s/^$ssh_setting.*/${ssh_config}/" "${include_dir}01-mscp-ssh.conf" || echo "$ssh_config" >> "${include_dir}01-mscp-ssh.conf" for u in $(/usr/bin/dscl . list /users shell | /usr/bin/egrep -v '(^_)|(root)|(/usr/bin/false)' | /usr/bin/awk '{print $1}'); do config=$(/usr/bin/sudo -u $u /usr/bin/ssh -Gv . 2>&1) configfiles=$(echo "$config" | /usr/bin/awk '/Reading configuration data/ {print $NF}'| /usr/bin/tr -d '\r') configarray=( ${(f)configfiles} ) if ! echo $config | /usr/bin/grep -q -i "$ssh_config" ; then for c in $configarray; do if [[ "$c" == "/etc/ssh/crypto.conf" ]]; then continue fi /usr/bin/sudo -u $u /usr/bin/grep -qEi "^$ssh_setting" "$c" && /usr/bin/sed -i "" "s/^$ssh_setting.*/${ssh_config}/I" "$c" if [[ "$c" =~ ".ssh/config" ]]; then if /usr/bin/grep -qEi "$ssh_setting" "$c" 2> /dev/null; then old_file=$(cat ~$u/.ssh/config) echo "$ssh_config" > ~$u/.ssh/config echo "$old_file" >> ~$u/.ssh/config fi fi done fi done done