diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers/rule.yml b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers/rule.yml index abcebf60c..50c7d689a 100644 --- a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers/rule.yml +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers/rule.yml @@ -61,7 +61,6 @@ references: nist-csf: PR.AC-1,PR.AC-3,PR.AC-4,PR.AC-6,PR.AC-7,PR.IP-1,PR.PT-1,PR.PT-3,PR.PT-4 srg: SRG-OS-000033-GPOS-00014,SRG-OS-000120-GPOS-00061,SRG-OS-000125-GPOS-00065,SRG-OS-000250-GPOS-00093,SRG-OS-000393-GPOS-00173,SRG-OS-000394-GPOS-00174 vmmsrg: SRG-OS-000033-VMM-000140,SRG-OS-000120-VMM-000600,SRG-OS-000478-VMM-001980,SRG-OS-000396-VMM-001590 - stigid@rhel7: RHEL-07-040110 isa-62443-2013: 'SR 1.1,SR 1.10,SR 1.11,SR 1.12,SR 1.13,SR 1.2,SR 1.3,SR 1.4,SR 1.5,SR 1.6,SR 1.7,SR 1.8,SR 1.9,SR 2.1,SR 2.10,SR 2.11,SR 2.12,SR 2.2,SR 2.3,SR 2.4,SR 2.5,SR 2.6,SR 2.7,SR 2.8,SR 2.9,SR 3.1,SR 3.5,SR 3.8,SR 4.1,SR 4.3,SR 5.1,SR 5.2,SR 5.3,SR 7.1,SR 7.6' isa-62443-2009: 4.3.3.2.2,4.3.3.3.9,4.3.3.5.1,4.3.3.5.2,4.3.3.5.3,4.3.3.5.4,4.3.3.5.5,4.3.3.5.6,4.3.3.5.7,4.3.3.5.8,4.3.3.6.1,4.3.3.6.2,4.3.3.6.3,4.3.3.6.4,4.3.3.6.5,4.3.3.6.6,4.3.3.6.7,4.3.3.6.8,4.3.3.6.9,4.3.3.7.1,4.3.3.7.2,4.3.3.7.3,4.3.3.7.4,4.3.4.3.2,4.3.4.3.3,4.3.4.4.7,4.4.2.1,4.4.2.2,4.4.2.4 cobit5: APO11.04,APO13.01,BAI03.05,BAI10.01,BAI10.02,BAI10.03,BAI10.05,DSS01.04,DSS05.02,DSS05.03,DSS05.04,DSS05.05,DSS05.07,DSS05.10,DSS06.03,DSS06.06,DSS06.10,MEA02.01 diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/ansible/shared.yml b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/ansible/shared.yml new file mode 100644 index 000000000..4796a2eab --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/ansible/shared.yml @@ -0,0 +1,13 @@ +# platform = Red Hat Enterprise Linux 7,Oracle Linux 7 +# reboot = false +# strategy = restrict +# complexity = low +# disruption = low + +- name: "Configure sshd to use approved ciphers" + lineinfile: + path: /etc/ssh/sshd_config + line: 'Ciphers aes256-ctr,aes192-ctr,aes128-ctr' + state: present + regexp: '^[\s]*[Cc]iphers[\s]+(aes256-ctr(?=[\w,-@]+|$),?)?(aes192-ctr(?=[\w,-@]+|$),?)?(aes128-ctr(?=[\w,-@]+|$),?)?[\s]*(?:#.*)?$' + create: True diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/bash/shared.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/bash/shared.sh new file mode 100644 index 000000000..8f751ed51 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/bash/shared.sh @@ -0,0 +1,7 @@ +# platform = multi_platform_wrlinux,Red Hat Enterprise Linux 7,Oracle Linux 7 + +if grep -q -P '^\s*[Cc]iphers\s+' /etc/ssh/sshd_config; then + sed -i 's/^\s*[Cc]iphers.*/Ciphers aes256-ctr,aes192-ctr,aes128-ctr/' /etc/ssh/sshd_config +else + echo "Ciphers aes256-ctr,aes192-ctr,aes128-ctr" >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/oval/shared.xml b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/oval/shared.xml new file mode 100644 index 000000000..53ff0a2a9 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/oval/shared.xml @@ -0,0 +1,38 @@ + + + {{{ oval_metadata("Limit the ciphers to those which are FIPS-approved.") }}} + + + + + + + + + + + + + + + + + + + + + + /etc/ssh/sshd_config + ^[\s]*(?i)Ciphers(?-i)[\s]+(?=[\w]+)(aes256-ctr(?=[\w,]+|$),?)?(aes192-ctr(?=[\w,]+|$),?)?(aes128-ctr)?[\s]*(?:#.*)?$ + 1 + + + diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/rule.yml b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/rule.yml new file mode 100644 index 000000000..075106417 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/rule.yml @@ -0,0 +1,64 @@ +documentation_complete: true + +prodtype: rhel7 + +title: 'Use Only FIPS 140-2 Validated Ciphers' + +description: |- + Limit the ciphers to those algorithms which are FIPS-approved. + The following line in /etc/ssh/sshd_config + demonstrates use of FIPS-approved ciphers: +
Ciphers aes256-ctr,aes192-ctr,aes128-ctr
+ This rule ensures that there are configured ciphers mentioned + above (or their subset), keeping the given order of algorithms. + +rationale: |- + 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 system data may be compromised. +
+ 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 industry and government requirements. For government systems, this allows + Security Levels 1, 2, 3, or 4 for use on {{{ full_name }}}. + +severity: medium + +identifiers: + cce@rhel7: CCE-83398-8 + +references: + disa: CCI-000068,CCI-000366,CCI-000803,CCI-000877,CCI-002890,CCI-003123 + srg: SRG-OS-000033-GPOS-00014,SRG-OS-000120-GPOS-00061,SRG-OS-000125-GPOS-00065,SRG-OS-000250-GPOS-00093,SRG-OS-000393-GPOS-00173,SRG-OS-000394-GPOS-00174 + stigid@rhel7: RHEL-07-040110 + +ocil_clause: 'FIPS ciphers are not configured or the enabled ciphers are not FIPS-approved' + +ocil: |- + Only FIPS ciphers should be used. To verify that only FIPS-approved + ciphers are in use, run the following command: +
$ sudo grep Ciphers /etc/ssh/sshd_config
+ The output should contain only following ciphers (or a subset) in the exact order: +
aes256-ctr,aes192-ctr,aes128-ctr
+ +warnings: + - general: |- + The system needs to be rebooted for these changes to take effect. + - regulatory: |- + System Crypto Modules must be provided by a vendor that undergoes + FIPS-140 certifications. + FIPS-140 is applicable to all Federal agencies that use + cryptographic-based security systems to protect sensitive information + in computer and telecommunication systems (including voice systems) as + defined in Section 5131 of the Information Technology Management Reform + Act of 1996, Public Law 104-106. This standard shall be used in + designing and implementing cryptographic modules that Federal + departments and agencies operate or are operated for them under + contract. See {{{ weblink(link="https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.140-2.pdf") }}} + To meet this, the system has to have cryptographic software provided by + a vendor that has undergone this certification. This means providing + documentation, test results, design information, and independent third + party review by an accredited lab. While open source software is + capable of meeting this, it does not meet FIPS-140 unless the vendor + submits to this process. diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/comment.fail.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/comment.fail.sh new file mode 100644 index 000000000..daff7d7c5 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/comment.fail.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/# ciphers aes256-ctr,aes192-ctr,aes128-ctr/" /etc/ssh/sshd_config +else + echo "# ciphers aes256-ctr,aes192-ctr,aes128-ctr" >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_reduced_list.pass.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_reduced_list.pass.sh new file mode 100644 index 000000000..b9d22262a --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_reduced_list.pass.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/Ciphers aes192-ctr,aes128-ctr/" /etc/ssh/sshd_config +else + echo "Ciphers aes192-ctr,aes128-ctr" >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_scrambled.fail.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_scrambled.fail.sh new file mode 100644 index 000000000..b99d3832c --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_scrambled.fail.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/Ciphers aes128-ctr,aes192-ctr,aes256-ctr/" /etc/ssh/sshd_config +else + echo "Ciphers aes128-ctr,aes192-ctr,aes256-ctr" >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_value.pass.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_value.pass.sh new file mode 100644 index 000000000..6dfd54631 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/correct_value.pass.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/ciphers aes256-ctr,aes192-ctr,aes128-ctr/" /etc/ssh/sshd_config +else + echo 'ciphers aes256-ctr,aes192-ctr,aes128-ctr' >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/line_not_there.fail.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/line_not_there.fail.sh new file mode 100644 index 000000000..7b38914a1 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/line_not_there.fail.sh @@ -0,0 +1,3 @@ +#!/bin/bash + +sed -i "/^Ciphers.*/d" /etc/ssh/sshd_config diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/no_parameters.fail.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/no_parameters.fail.sh new file mode 100644 index 000000000..6fdb47093 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/no_parameters.fail.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/Ciphers /" /etc/ssh/sshd_config +else + echo 'Ciphers ' >> /etc/ssh/sshd_config +fi diff --git a/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/wrong_value.fail.sh b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/wrong_value.fail.sh new file mode 100644 index 000000000..24fdf0f30 --- /dev/null +++ b/linux_os/guide/services/ssh/ssh_server/sshd_use_approved_ciphers_ordered_stig/tests/wrong_value.fail.sh @@ -0,0 +1,7 @@ +#!/bin/bash + +if grep -q "^Ciphers" /etc/ssh/sshd_config; then + sed -i "s/^Ciphers.*/ Ciphers aes128-ctr,aes192-ctr,weak-cipher,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc,rijndael-cbc@lysator\.liu\.se/" /etc/ssh/sshd_config +else + echo " Ciphers aes128-ctr,aes192-ctr,weak-cipher,aes128-cbc,aes192-cbc,aes256-cbc,3des-cbc,rijndael-cbc@lysator\.liu\.se" >> /etc/ssh/sshd_config +fi diff --git a/rhel7/profiles/stig.profile b/rhel7/profiles/stig.profile index 88b50d5ef..ecd256c68 100644 --- a/rhel7/profiles/stig.profile +++ b/rhel7/profiles/stig.profile @@ -239,8 +239,7 @@ selections: - install_antivirus - accounts_max_concurrent_login_sessions - configure_firewalld_ports - - sshd_approved_ciphers=stig - - sshd_use_approved_ciphers + - sshd_use_approved_ciphers_ordered_stig - accounts_tmout - sshd_enable_warning_banner - sssd_ldap_start_tls