The ESXi host must configure virtual switch security policies to reject Media Access Control (MAC) address changes.
An XCCDF Rule
Description
<VulnDiscussion>If the virtual machine (VM) operating system changes the MAC address, it can send frames with an impersonated source MAC address at any time. This allows it to stage malicious attacks on the devices in a network by impersonating a network adaptor authorized by the receiving network. This will prevent VMs from changing their effective MAC address, which will affect applications that require this functionality. This will also affect how a layer 2 bridge will operate and will affect applications that require a specific MAC address for licensing. "Reject MAC Changes" can be set at the vSwitch and/or the Portgroup level. Switch-level settings can be overridden at the Portgroup level.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-258772r933377_rule
- Severity
- High
- References
- Updated
Remediation - Manual Procedure
From the vSphere Client, go to Hosts and Clusters.
Select the ESXi Host >> Configure >> Networking >> Virtual Switches.
On each standard switch, click "Edit" and select Security.