Nutanix OS must implement cryptography to protect the integrity of remote access sessions.

Without cryptographic integrity protections, information can be altered by unauthorized users without detection.

Remote access (e.g., RDP) is access to DoW nonpublic information systems by an authorized user (or an information system) communicating through an external, nonorganization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless.

Cryptographic mechanisms used for protecting the integrity of information include, for example, signed hash functions using asymmetric cryptography enabling distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash.

Note: For AHV, this requirement is Not Applicable.

Verify AOS, Prism Central, and Files OS VMs are configured to use only FIPS-validated key exchange algorithms using the following command.

$ sudo grep -i kexalgorithms /etc/crypto-policies/back-ends/opensshserver.config CRYPTO_POLICY='-oKexAlgorithms=ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512'

If the entries following "KexAlgorithms" are not "ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512", appear in a different order than shown, or are missing or commented out, this is a finding.

Configure SSH.

1. For AOS, configure SSH, then restart the SSH for the changes to take effect.

$ sudo salt-call state.sls security/CVM/sshdCVM
$ sudo systemctl restart sshd

2. For Prism Central, configure SSH, then restart the SSH for the changes to take effect.

$ sudo salt-call state.sls security/PCVM/sshdPCVM
$ sudo systemctl restart sshd

3. For Files, configure SSH, then restart the SSH for the changes to take effect.

$ sudo salt-call state.sls security/AFS/sshdAFS
$ sudo systemctl restart sshd