The vCenter Server must not configure VLAN Trunking unless Virtual Guest Tagging (VGT) is required and authorized.
An XCCDF Rule
Description
<VulnDiscussion>When a port group is set to VLAN Trunking, the vSwitch passes all network frames in the specified range to the attached virtual machines without modifying the virtual local area network (VLAN) tags. In vSphere, this is referred to as VGT. The virtual machine must process the VLAN information itself via an 802.1Q driver in the operating system. VLAN Trunking must only be implemented if the attached virtual machines have been specifically authorized and are capable of managing VLAN tags themselves. If VLAN Trunking is enabled inappropriately, it may cause a denial of service or allow a virtual machine to interact with traffic on an unauthorized VLAN.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-258940r934478_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
From the vSphere Client, go to "Networking".
Select a distributed switch >> Select a distributed port group >> Configure >> Settings >> Policies.
Click "Edit".