Information
Privileged access contains control and configuration information and is particularly sensitive, so additional protections are necessary. This is maintained by using cryptographic mechanisms such as encryption to protect confidentiality.
Nonlocal maintenance and diagnostic activities are activities conducted by individuals communicating through a network, either an external network (e.g., the internet) or an internal network. Local maintenance and diagnostic activities are activities carried out by individuals physically present at the information system or information system component and not communicating across a network connection.
This requirement applies to hardware/software diagnostic test equipment or tools. This requirement does not cover hardware/software components that may support information system maintenance, yet are a part of the system (e.g., the software implementing 'ping,' 'ls,' 'ipconfig,' or the hardware and software implementing the monitoring port of an Ethernet switch).
The operating system can meet this requirement through leveraging a cryptographic module.
Satisfies: SRG-OS-000394-GPOS-00174, SRG-OS-000424-GPOS-00188, SRG-OS-000478-GPOS-00223
Solution
Open /etc/ssh/sshd_config with a text editor.
Ensure that the 'Ciphers' line is uncommented and set to the following:
Ciphers [email protected],[email protected],aes256-ctr,aes192-ctr,aes128-ctr
At the command line, execute the following command:
# service sshd reload