Protect against MAC address spoofing
By default this feature is turned on. If left as the default of accept then a potential attacker could spoof MAC addresses and potentially appear as a trusted host.
Remediation
- Login to VirtualCenter or your ESX host using the VI Client
- Select the configuration tab for your ESX host
- Select networking from the hardware pane
- Select the properties for the vswitch you wish to change
- Select Edit from the ports tab
- Select the security tab
- Change the “MAC address spoofing setting to Reject”
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