Title

The operating system must implement cryptography to protect the integrity of remote access sessions. (Cat II impact)

Discussion

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, non-organization-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. Satisfies: SRG-OS-000250-GPOS-00093, SRG-OS-000393-GPOS-00173, SRG-OS-000394-GPOS-00174

Check Content

Verify the operating system implements cryptography to protect the integrity of remote access sessions. If it does not, this is a finding. Verify the SSH daemon is configured to only use MACs employing FIPS 140-2 approved ciphers. Check that the SSH daemon is configured to only use MACs employing FIPS 140-2 approved ciphers with the following command: # grep -i macs /etc/ssh/sshd_config MACs hmac-sha2-256,hmac-sha2-512 If any ciphers other than "hmac-sha2-256" or "hmac-sha2-512" are listed or the returned line is commented out, or does not exist, this is a finding.

Fix Text

Configure the operating system to implement cryptography to protect the integrity of remote access sessions.

Additional Identifiers

Rule ID:

Vulnerability ID: V-930

Group Title:

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.