id: auth_ssh_password_authentication_disable
title: Disable Password Authentication for SSH
discussion: |
  If remote login through SSH is enabled, password based authentication _MUST_ be disabled for user login.

  All users _MUST_ go through multifactor authentication to prevent unauthenticated access and potential compromise to the system.

  NOTE: /etc/ssh/sshd_config will be automatically modified to its original state following any update or major upgrade to the operating system.
check: |
  /usr/sbin/sshd -G | /usr/bin/grep -Ec '^(passwordauthentication\s+no|kbdinteractiveauthentication\s+no)'
result:
  integer: 2
fix: |
  [source,bash]
  ----
  include_dir=$(/usr/bin/awk '/^Include/ {print $2}' /etc/ssh/sshd_config | /usr/bin/tr -d '*')
  if [[ -z $include_dir ]]; then
    /usr/bin/sed -i.bk "1s/.*/Include \/etc\/ssh\/sshd_config.d\/\*/" /etc/ssh/sshd_config
  fi
  echo "passwordauthentication no" >> "${include_dir}01-mscp-sshd.conf"
  echo "kbdinteractiveauthentication no" >> "${include_dir}01-mscp-sshd.conf"

  for file in $(ls ${include_dir}); do
    if [[ "$file" == "100-macos.conf" ]]; then
        continue
    fi
    if [[ "$file" == "01-mscp-sshd.conf" ]]; then
        break
    fi
    /bin/mv ${include_dir}${file} ${include_dir}20-${file}
  done
  ----
references:
  cce:
    - CCE-94139-3
  cci:
    - CCI-000186
    - CCI-000765
    - CCI-000766
    - CCI-000767
    - CCI-000768
    - CCI-000877
    - CCI-001941
    - CCI-001948
    - CCI-004046
  800-53r5:
    - IA-2(1)
    - IA-2(2)
    - IA-2(6)
    - IA-2
    - IA-5(2)
    - MA-4
    - IA-2(8)
  800-53r4:
    - IA-2
    - IA-2(1)
    - IA-2(2)
    - IA-2(3)
    - IA-2(4)
    - IA-2(6)
    - IA-2(11)
    - IA-5(2)
    - IA-5(11)
    - MA-4
  srg:
    - SRG-OS-000107-GPOS-00054
    - SRG-OS-000112-GPOS-00057
    - SRG-OS-000067-GPOS-00035
    - SRG-OS-000108-GPOS-00055
    - SRG-OS-000125-GPOS-00065
    - SRG-OS-000106-GPOS-00053
    - SRG-OS-000375-GPOS-00160
    - SRG-OS-000105-GPOS-00052
  disa_stig:
    - APPL-15-001150
  800-171r3:
    - 03.05.01
    - 03.05.03
    - 03.05.04
    - 03.07.05
  cis:
    benchmark:
      - N/A
    controls v8:
      - 6.3
      - 6.4
      - 6.5
  cmmc:
    - IA.L1-3.5.1
    - IA.L1-3.5.2
    - IA.L2-3.5.3
    - IA.L2-3.5.4
    - MA.L2-3.7.5
macOS:
  - '15.0'
tags:
  - 800-53r5_low
  - 800-53r5_moderate
  - 800-53r5_high
  - 800-53r4_low
  - 800-53r4_moderate
  - 800-53r4_high
  - 800-171
  - cisv8
  - cnssi-1253_low
  - cnssi-1253_high
  - cmmc_lvl2
  - cmmc_lvl1
  - stig
  - cnssi-1253_moderate
severity: high
mobileconfig: false
mobileconfig_info:
ddm_info:
  declarationtype: com.apple.configuration.services.configuration-files
  service: com.apple.sshd
  config_file: sshd_config
  configuration_key: KbdInteractiveAuthentication
  configuration_value: no