4.6 Ensure to set SSH MAC algorithm to hmac-sha2-256

Information

To set strong Hashing algorithm

Rationale:

Impact:

Weak MAC algorithms make it possible for attackers to bypass authentication , steal keys and reduce the integrity capability that SSH provides for remote connections.

Solution

1-Log in to tmsh by typing the following command:tmsh

2-To modify the sshd configuration, type the following command to start the vi editor:edit /sys sshd all-properties

3-To change the list of ciphers, you can navigate to the line that starts with the include statement, and use the keyword MACs ,and adding the list of desired MACs to the 2-line include statement:
include 'Ciphers aes128-cbc,aes128-ctr,aes192-ctr,aes256-ctr,arcfour128,arcfour256,arcfour
MACs hmac-sha2-256'

See Also

https://workbench.cisecurity.org/files/3587

Item Details

Category: CONFIGURATION MANAGEMENT, SYSTEM AND SERVICES ACQUISITION

References: 800-53|CM-1, 800-53|CM-2, 800-53|CM-6, 800-53|CM-7, 800-53|CM-7(1), 800-53|CM-9, 800-53|SA-3, 800-53|SA-8, 800-53|SA-10, CSCv7|5.1

Plugin: F5

Control ID: 9f646396b82b0d416b5338c88bcfa1dff86d49656fef8ab84b36f8deb8617c19