Check: VCTR-67-000016
VMware vSphere 6.7 vCenter STIG:
VCTR-67-000016
(in versions v1 r4 through v1 r2)
Title
The vCenter Server must only send NetFlow traffic to authorized collectors. (Cat II impact)
Discussion
The distributed virtual switch can export NetFlow information about traffic crossing the switch. NetFlow exports are not encrypted and can contain information about the virtual network, making it easier for a MitM attack to be executed successfully. If NetFlow export is required, verify that all NetFlow target IPs are correct.
Check Content
If distributed switches are not used, this is not applicable. To view NetFlow Collector IPs configured on distributed switches: From the vSphere Client, go to Networking >> select a distributed switch >> Configure >> Settings >> NetFlow. View the NetFlow pane and verify that any collector IP addresses are valid and in use for troubleshooting. or From a PowerCLI command prompt while connected to the vCenter server, run the following command: Get-VDSwitch | select Name,@{N="NetFlowCollectorIPs";E={$_.ExtensionData.config.IpfixConfig.CollectorIpAddress}} To view if NetFlow is enabled on any distributed port groups: From the vSphere Client, go to Networking >> select a distributed port group >> Manage >> Settings >> Policies. Go to Monitoring and view the NetFlow status. or From a PowerCLI command prompt while connected to the vCenter server, run the following command: Get-VDPortgroup | select Name,VirtualSwitch,@{N="NetFlowEnabled";E={$_.Extensiondata.Config.defaultPortConfig.ipfixEnabled.Value}} If NetFlow is configured and the collector IP is not known and documented, this is a finding.
Fix Text
To remove collector IPs: From the vSphere Client, go to Networking >> select a distributed switch >> Configure >> Settings >> NetFlow. Click "Edit" and remove any unknown collector IPs. or From a PowerCLI command prompt while connected to the vCenter server, run the following commands: $dvs = Get-VDSwitch dvswitch | Get-View ForEach($vs in $dvs){ $spec = New-Object VMware.Vim.VMwareDVSConfigSpec $spec.configversion = $vs.Config.ConfigVersion $spec.IpfixConfig = New-Object VMware.Vim.VMwareIpfixConfig $spec.IpfixConfig.CollectorIpAddress = "" $spec.IpfixConfig.CollectorPort = "0" $spec.IpfixConfig.ActiveFlowTimeout = "60" $spec.IpfixConfig.IdleFlowTimeout = "15" $spec.IpfixConfig.SamplingRate = "0" $spec.IpfixConfig.InternalFlowsOnly = $False $vs.ReconfigureDvs_Task($spec) } Note: This will reset the NetFlow collector configuration back to the defaults. To disable NetFlow on a distributed port group: From the vSphere Client, go to Networking >> select a distributed port group >> Manage >> Settings >> Policies. Go to "Monitoring" and change "NetFlow" to disabled. or From a PowerCLI command prompt while connected to the vCenter server, run the following commands: $pgs = Get-VDPortgroup | Get-View ForEach($pg in $pgs){ $spec = New-Object VMware.Vim.DVPortgroupConfigSpec $spec.configversion = $pg.Config.ConfigVersion $spec.defaultPortConfig = New-Object VMware.Vim.VMwareDVSPortSetting $spec.defaultPortConfig.ipfixEnabled = New-Object VMware.Vim.BoolPolicy $spec.defaultPortConfig.ipfixEnabled.inherited = $false $spec.defaultPortConfig.ipfixEnabled.value = $false $pg.ReconfigureDVPortgroup_Task($spec) }
Additional Identifiers
Rule ID: SV-243085r879887_rule
Vulnerability ID: V-243085
Group Title: SRG-APP-000516
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |