The ESXi host Secure Shell (SSH) daemon must set a timeout interval on idle sessions.

Automatically logging out idle users guards against compromises via hijacked administrative sessions.

From an ESXi shell, run the following command:

# esxcli system ssh server config list -k clientaliveinterval

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 'clientaliveinterval'}

Example result:

clientaliveinterval 200

If "clientaliveinterval" is not configured to "200", this is a finding.

From an ESXi shell, run the following command:

# esxcli system ssh server config set -k clientaliveinterval -v 200

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 = 'clientaliveinterval' $arguments.value = '200' $esxcli.system.ssh.server.config.set.Invoke($arguments)