The ESXi host must configure the firewall to block network traffic by default.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-256418 | ESXI-70-000057 | SV-256418r959010_rule | CCI-000366 | medium |
| Description | ||||
| In addition to service-specific firewall rules, ESXi has a default firewall rule policy to allow or deny incoming and outgoing traffic. Reduce the risk of attack by ensuring this is set to deny incoming and outgoing traffic. | ||||
| STIG | Date | |||
| VMware vSphere 7.0 ESXi Security Technical Implementation Guide | 2025-02-11 | |||
Details
Check Text (C-256418r959010_chk)
From an ESXi shell, run the following command:
# esxcli network firewall get
If the "Default Action" does not equal "DROP", this is a finding.
or
From a PowerCLI command prompt while connected to the ESXi host, run the following command:
Get-VMHostFirewallDefaultPolicy
If the Incoming or Outgoing policies are "True", this is a finding.
Fix Text (F-60036r886034_fix)
From an ESXi shell, run the following command:
# esxcli network firewall set --default-action=false
or
From a PowerCLI command prompt while connected to the ESXi host, run the following command:
Get-VMHostFirewallDefaultPolicy | Set-VMHostFirewallDefaultPolicy -AllowIncoming $false -AllowOutgoing $false