The AIX SSH daemon must not allow compression.

If compression is allowed in an SSH connection prior to authentication, vulnerabilities in the compression software could result in compromise of the system from an unauthenticated connection, potentially with root privileges.

Note: If the installed version of OpenSSH is 7.4 or above, this requirement is not applicable.

Check the SSH daemon configuration for the Compression setting by running: # grep -i Compression /etc/ssh/sshd_config | grep -v '^#' Compression no

If the setting is not present, or it is not set to "no", this is a finding.

Edit the "/etc/ssh/sshd_config" file and add (or modify) the following line: Compression no

Restart the SSH daemon: # stopsrc -s sshd # startsrc -s sshd