Title

RHEL 9 SSHD must not allow blank passwords. (Cat I impact)

Discussion

If an account has an empty password, anyone could log on and run commands with the privileges of that account. Accounts with empty passwords should never be used in operational environments. Satisfies: SRG-OS-000106-GPOS-00053, SRG-OS-000480-GPOS-00229, SRG-OS-000480-GPOS-00227

Check Content

Verify that RHEL 9 remote access using SSH prevents logging on with a blank password 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*permitemptypasswords' PermitEmptyPasswords no If the "PermitEmptyPasswords" keyword is set to "yes", is missing, or is commented out, this is a finding.

Fix Text

To configure the system to prevent SSH users from logging on with blank passwords edit the following line in "/etc/ssh/sshd_config" or in a file in "/etc/ssh/sshd_config.d": PermitEmptyPasswords no Restart the SSH daemon for the settings to take effect: $ sudo systemctl restart sshd.service

Additional Identifiers

Rule ID: SV-257984r1045026_rule

Vulnerability ID: V-257984

Group Title: SRG-OS-000106-GPOS-00053

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