Title

Informational messages from the virtual machine to the VMX file must be limited on the virtual machine (VM). (Cat III impact)

Discussion

The configuration file containing these name-value pairs is limited to a size of 1MB. If not limited, VMware tools in the guest operating system are capable of sending a large and continuous data stream to the host. This 1MB capacity should be sufficient for most cases, but this value can change if necessary. The value can be increased if large amounts of custom information are being stored in the configuration file. The default limit is 1MB.

Check Content

From the vSphere Client, right-click the Virtual Machine and go to Edit Settings >> VM Options >> Advanced >> Configuration Parameters >> Edit Configuration. Verify the "tools.setinfo.sizeLimit" value is set to "1048576". or From a PowerCLI command prompt while connected to the ESXi host or vCenter server, run the following command: Get-VM "VM Name" | Get-AdvancedSetting -Name tools.setinfo.sizeLimit If the virtual machine advanced setting "tools.setinfo.sizeLimit" does not exist or is not set to "1048576", this is a finding.

Fix Text

From the vSphere Client, right-click the Virtual Machine and go to Edit Settings >> VM Options >> Advanced >> Configuration Parameters >> Edit Configuration. Find the "tools.setinfo.sizeLimit" value and set it to "1048576". If the setting does not exist, add the Name and Value setting at the bottom of screen. Note: The VM must be powered off to configure the advanced settings through the vSphere Client. Therefore, it is recommended to configure these settings with PowerCLI as this can be done while the VM is powered on. Settings do not take effect via either method until the virtual machine is cold started, not rebooted. or From a PowerCLI command prompt while connected to the ESXi host or vCenter server, run the provided commands as shown below. If the setting does not exist, run: Get-VM "VM Name" | New-AdvancedSetting -Name tools.setinfo.sizeLimit -Value 1048576 If the setting exists, run: Get-VM "VM Name" | Get-AdvancedSetting -Name tools.setinfo.sizeLimit | Set-AdvancedSetting -Value 1048576

Additional Identifiers

Rule ID: SV-256463r886432_rule

Vulnerability ID: V-256463

Group Title: SRG-OS-000480-VMM-002000

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