Title

RHEL 9 must not allow a noncertificate trusted host SSH logon to the system. (Cat II impact)

Discussion

SSH trust relationships mean a compromise on one host can allow an attacker to move trivially to other hosts.

Check Content

Verify the operating system does not allow a noncertificate trusted host SSH logon to the system with the following command: $ sudo /usr/sbin/sshd -dd 2>&1 | awk '/filename/ {print $4}' | tr -d '\r' | tr '\n' ' ' | xargs sudo grep -iH '^\s*hostbasedauthentication' HostbasedAuthentication no If the "HostbasedAuthentication" keyword is not set to "no", is missing, or is commented out, this is a finding. If the required value is not set, this is a finding.

Fix Text

To configure RHEL 9 to not allow a noncertificate trusted host SSH logon to the system add or modify the following line in "/etc/ssh/sshd_config". HostbasedAuthentication no Restart the SSH daemon for the settings to take effect: $ sudo systemctl restart sshd.service

Additional Identifiers

Rule ID: SV-257992r952190_rule

Vulnerability ID: V-257992

Group Title: SRG-OS-000480-GPOS-00229

Expert Comments

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