The SSH daemon must be configured to not allow TCP connection forwarding.

From VMware ESXi Server 5.0 Security Technical Implementation Guide

Associated with: CCI-000366

SV-51064r1_rule The SSH daemon must be configured to not allow TCP connection forwarding.

Vulnerability discussion

SSH TCP connection forwarding provides a mechanism to establish TCP connections proxied by the SSH server. This function can provide similar convenience to a Virtual Private Network (VPN) with the similar risk of providing a path to circumvent firewalls and network ACLs.

Check content

Disable lock down mode. Enable the ESXi Shell. Check the SSH daemon configuration for the TCP connection forwarding setting. # grep -i AllowTCPForwarding /etc/ssh/sshd_config | grep -v '^#' If "AllowTCPForwarding" is set to "yes", this is a finding. Re-enable lock down mode.

Fix text

Disable lock down mode. Enable the ESXi Shell. Edit the SSH daemon configuration and add/modify the "AllowTCPForwarding" configuration setting it to "no". # vi /etc/ssh/sshd_config Re-enable lock down mode.

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