The ESXi host Secure Shell (SSH) daemon must disable port forwarding.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-258785	SRG-OS-000480-VMM-002000	ESXI-80-000230	SV-258785r933416_rule	2023-10-11	1

Description
While enabling Transmission Control Protocol (TCP) tunnels is a valuable function of sshd, this feature is not appropriate for use on the ESXi hypervisor.

ℹ️ Check
From an ESXi shell, run the following command: # esxcli system ssh server config list -k allowtcpforwarding or From a PowerCLI command prompt while connected to the ESXi host, run the following commands: $esxcli = Get-EsxCli -v2 $esxcli.system.ssh.server.config.list.invoke() \| Where-Object {$_.Key -eq 'allowtcpforwarding'} Example result: allowtcpforwarding no If "allowtcpforwarding" is not configured to "no", this is a finding.

ℹ️ Check

From an ESXi shell, run the following command: # esxcli system ssh server config list -k allowtcpforwarding or From a PowerCLI command prompt while connected to the ESXi host, run the following commands: $esxcli = Get-EsxCli -v2 $esxcli.system.ssh.server.config.list.invoke() | Where-Object {$_.Key -eq 'allowtcpforwarding'} Example result: allowtcpforwarding no If "allowtcpforwarding" is not configured to "no", this is a finding.

✔️ Fix
From an ESXi shell, run the following command: # esxcli system ssh server config set -k allowtcpforwarding -v no or From a PowerCLI command prompt while connected to the ESXi host, run the following commands: $esxcli = Get-EsxCli -v2 $arguments = $esxcli.system.ssh.server.config.set.CreateArgs() $arguments.keyword = 'allowtcpforwarding' $arguments.value = 'no' $esxcli.system.ssh.server.config.set.Invoke($arguments)

✔️ Fix

From an ESXi shell, run the following command: # esxcli system ssh server config set -k allowtcpforwarding -v no or From a PowerCLI command prompt while connected to the ESXi host, run the following commands: $esxcli = Get-EsxCli -v2 $arguments = $esxcli.system.ssh.server.config.set.CreateArgs() $arguments.keyword = 'allowtcpforwarding' $arguments.value = 'no' $esxcli.system.ssh.server.config.set.Invoke($arguments)