Details

When promiscuous mode is enabled for a virtual switch all virtual machines connected to the Portgroup have the potential of reading all packets across that network, meaning only the virtual machines connected to that Portgroup. Promiscuous mode is disabled by default on the ESXi Server, and this is the recommended setting.

NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.

Solution

From the vSphere Web Client go to Networking >> Select a distributed switch >> Select a port group >> Configure >> Settings >> Policies >> Edit >> Security. Set ‘Promiscuous Mode’ to reject. Click ‘OK’.

or

From a PowerCLI command prompt while connected to the vCenter server run the following commands:
Get-VDSwitch | Get-VDSecurityPolicy | Set-VDSecurityPolicy -AllowPromiscuous $false
Get-VDPortgroup | ?{$_.IsUplink -eq $false} | Get-VDSecurityPolicy | Set-VDSecurityPolicy -AllowPromiscuous $false

Supportive Information

The following resource is also helpful.

• https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_VMW_vSphere_6-5_Y21M10_STIG.zip

This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management.This control applies to the following type of system VMware.

References

• 800-53|CM-6b.
• CAT|II
• CCI|CCI-000366
• Rule-ID|SV-216837r612237_rule
• STIG-ID|VCWN-65-000015
• STIG-Legacy|SV-104571
• STIG-Legacy|V-94741
• Vuln-ID|V-216837

Source

• Tenable.com/audits