GEN005505 - The operating system must implement DoD-approved encryption to protect the confidentiality of SSH connections.

Information

DoD information systems are required to use FIPS 140-2 approved ciphers. SSHv2 ciphers meeting this requirement are 3DES and AES.

By specifying a cipher list with the order of ciphers being in a 'strongest to weakest' orientation, the system will automatically attempt to use the strongest cipher for securing SSH connections.

Solution

Edit the SSH daemon configuration and remove any ciphers not starting with 'aes' and remove any ciphers ending with 'cbc'.

If necessary, add a 'Ciphers' line.

Ciphers aes256-ctr,aes192-ctr,aes128-ctr

Restart the SSH daemon.

# /sbin/service sshd restart

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Oracle_Linux_5_V2R1_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-17(2), CAT|II, CCI|CCI-000068, Rule-ID|SV-218600r603337_rule, STIG-ID|GEN005505, STIG-Legacy|SV-63561, STIG-Legacy|V-22458, Vuln-ID|V-218600

Plugin: Unix

Control ID: e45cb14fdb90f7ad17e8ec1cd2e8304f39fa3231aa63fca4a361e7051bc194c2