OL6-00-000228 - The Oracle Linux operating system must be configured so that the SSH daemon is configured to only use Message Authentication Codes (MACs) employing FIPS 140-2 approved cryptographic hash algorithms.

Information

DoD information systems are required to use FIPS 140-2 approved cryptographic hash functions. The only SSHv2 hash algorithm meeting this requirement is SHA.

Solution

Edit the '/etc/ssh/sshd_config' file to uncomment or add the line for the 'MACs' keyword and set its value to 'hmac-sha2-256' and/or 'hmac-sha2-512' (this file may be named differently or be in a different location if using a version of SSH that is provided by a third-party vendor):

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

The SSH service must be restarted for changes to take effect.
# sudo service sshd restart

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Oracle_Linux_6_V1R18_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-13, CAT|II, CCI|CCI-001453, Rule-ID|SV-219958r603346_rule, STIG-ID|OL6-00-000228, STIG-Legacy|SV-109113, STIG-Legacy|V-100009, Vuln-ID|V-219958

Plugin: Unix

Control ID: e2748bd8a3249cd085d92c11f1c643d9c34ca498ac48e9a4d507127fb3151698