Configure SSH to use System Crypto Policy
Crypto Policies provide a centralized control over crypto algorithms usage of many packages.
SSH is supported by crypto policy, but the SSH configuration may be
set up to ignore it.
To check that Crypto Policies settings are configured correctly, ensure that
the CRYPTO_POLICY
variable is either commented or not set at all
in the /etc/sysconfig/sshd
.
Overriding the system crypto policy makes the behavior of the SSH service violate expectations,
and makes system configuration more fragmented.
The following script can be run on the host to remediate the issue.
#!/bin/bash
SSH_CONF="/etc/sysconfig/sshd"
sed -i "/^\s*CRYPTO_POLICY.*$/Id" $SSH_CONF
The following playbook can be run with Ansible to remediate the issue.
- name: Configure SSH to use System Crypto Policy
lineinfile:
dest: /etc/sysconfig/sshd
state: absent
regexp: (?i)^\s*CRYPTO_POLICY.*$
tags:
- CCE-80939-2
- DISA-STIG-RHEL-08-010287
- NIST-800-53-AC-17(2)
- NIST-800-53-AC-17(a)
- NIST-800-53-CM-6(a)
- NIST-800-53-MA-4(6)
- NIST-800-53-SC-13
- PCI-DSS-Req-2.2
- PCI-DSSv4-2.2
- PCI-DSSv4-2.2.7
- configure_ssh_crypto_policy
- disable_strategy
- low_complexity
- medium_disruption
- medium_severity
- reboot_required