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The Photon operating system must implement only approved Message Authentication Codes (MACs) to protect the integrity of remote access sessions.


Finding ID Version Rule ID IA Controls Severity
V-258900 PHTN-40-000239 SV-258900r933761_rule High
Without cryptographic integrity protections, information can be altered by unauthorized users without detection. Remote access (e.g., RDP) is access to DOD 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.
VMware vSphere 8.0 vCenter Appliance Photon OS 4.0 Security Technical Implementation Guide 2023-10-29


Check Text ( C-62640r933759_chk )
At the command line, run the following command to verify the running configuration of sshd:

# sshd -T|&grep -i MACs

Example result:

macs hmac-sha2-512,hmac-sha2-256

If the output matches the macs in the example result or a subset thereof, this is not a finding.

If the output contains any macs not listed in the example result, this is a finding.
Fix Text (F-62549r933760_fix)
Navigate to and open:


Ensure the "MACs" line is uncommented and set to the following:

MACs hmac-sha2-512,hmac-sha2-256

At the command line, run the following command:

# systemctl restart sshd.service