Information
The ESXi Firewall is enabled by default and allows ping (ICMP) and communication with
DHCP/DNS clients. Confirm that access to services are only allowed by authorized
IPs/networks to protect from outside attacks.
*Rationale*
Unrestricted access to services running on an ESXi host can expose a host to outside attacks
and unauthorized access. Reduce the risk by configuring the ESXi firewall to only allow
access from authorized networks.
NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.
Solution
Perform the following from the vSphere web client-
1. Select the host
2. Go to 'Manage' -> 'Settings' -> 'System' -> 'Security Profile'
3. In the 'Firewall' section select 'Edit...'.
4. For each enabled service, (e.g. ssh, vSphere Web Access, http client) provide a range
of allowed IP addresses.
5. Click 'Ok'.
Impact-Only systems in the IP whitelist/ACL will be able to connect to services on the ESXi server.
Default Value-The prescribed state is not the default state.