MeltdownSpectreReport

Query mitigation status of Meltdown and Spectre against one or multiple Windows computers. It uses parallelization for fast data collection.

Report includes

• Mitigation status for CVE-2017-5754 in Windows
• Mitigation status for CVE-2017-5715 in Windows
• Mitigation status for CVE-2017-5753 in Edge
• Mitigation status for CVE-2017-5753 in IE
• Mitigation status for CVE-2017-5753 in Chrome
• Mitigation status for CVE-2017-5753 in Firefox
• Information to assess the risk (CPU, Hyper-V, Terminal Server, Docker)
• Information for troubleshooting (Hardware Manufacturer and Model, Registry Keys, Uptime, Installed Hotfixes, ...)

It requires PowerShell 2.0 or later and PSRemoting enabled on remote systems.

The script includes Get-SpeculationControlSettings from Microsoft and Invoke-Parallel from RamblingCookieMonster. All credits for these functions go to them. Thank you!

Example

Execution against local computer

PS C:\> .\MeltdownSpectreReport.ps1 -ComputerName computer01
ComputerName                       : computer01
Manufacturer                       : HP
Model                              : HP Spectre x360 Convertible
BIOS                               : F.47
CPU                                : Intel(R) Core(TM) i7-6560U CPU @ 2.20GHz
OperatingSystem                    : Microsoft Windows 10 Pro
OSReleaseId                        : 1709
isHyperV                           : True
isTerminalServer                   : False
isDocker                           : True
CVE-2017-5754 mitigated            : True
CVE-2017-5715 mitigated            : False
CVE-2017-5753 mitigated in Edge    : True
CVE-2017-5753 mitigated in IE      : True
CVE-2017-5753 mitigated in Chrome  : False
CVE-2017-5753 mitigated in Firefox : True
BTIHardwarePresent                 : False
BTIWindowsSupportPresent           : True
BTIWindowsSupportEnabled           : False
BTIDisabledBySystemPolicy          : False
BTIDisabledByNoHardwareSupport     : True
KVAShadowRequired                  : True
KVAShadowWindowsSupportPresent     : True
KVAShadowWindowsSupportEnabled     : True
KVAShadowPcidEnabled               : True
OSMitigationRegKeySet              :
AVCompatibility                    : True
MinVmVersionForCpuBasedMitigations : 2.0
InstalledUpdates                   : {@{HotFixId=KB4048951; Description=Security Update; InstalledOn=15.11.2017 00:00:00; ComputerName=computer01},
@{HotFixId=KB4049179; Description=Security Update; InstalledOn=05.11.2017 00:00:00; ComputerName=computer01},...}
Uptime                             : 15:01:18.3875647
ExecutionDate                      : 06.01.2018

Execution against multiple computers

PS C:\> $ComputerName = Get-ADComputer -Filter * | Select-Object -ExpandProperty Name
$Report = .\MeltdownSpectreReport.ps1 -ComputerName $ComputerName
$Report | ConvertTo-Csv -NoTypeInformation -Delimiter ',' | Out-File C:\report.csv
$Report | Out-GridView

PS C:\> $ComputerName = Get-Content $env:USERPROFILE\Desktop\servers.txt
.\MeltdownSpectreReport.ps1 -ComputerName $ComputerName -ErrorAction SilentlyContinue | 
Export-Csv -Path $env:USERPROFILE\Desktop\servers.txt -NoTypeInformation

Properties

Mitigation Status

This highly relies on the information from Spectre still unfixed, unlike what Intel says and CPU security bugs caused by speculative execution. I highly recommend to read them.

Note: Not every mitigation, especially for CVE-2017-5753, is of the same quality. As the root cause relies in the CPU, all these mitigations are not really a fix to the actual problem. Mitigation means, it's "more difficult to exploit", and not every mitigation makes it equally difficult. The report only knows true or false for the mitigation. true is usually considered as "as good mitigated as currently possible"

CVE-2017-5754 mitigated (aka Meltdown)

Is true if CVE-2017-5754 mitigated if KVAShadowRequired is false, or if KVAShadowWindowsSupportPresent, KVAShadowWindowsSupportEnabled, and KVAShadowPcidEnabled are true. The test are actually done by Get-SpeculationControlSettings].

CVE-2017-5715 mitigated (aka Spectre Variant 2)

Is true if BTIHardwarePresent, BTIWindowsSupportPresent, and BTIWindowsSupportEnabled are true. The test are actually done by Get-SpeculationControlSettings]

CVE-2017-5753 mitigated in Edge (aka Spectre Variant 1)

Is true if one of the following Windows Updates is installed: 'KB4056893', 'KB4056890', 'KB4056891', 'KB4056892', 'KB4056888'

The list of updates was obtained from ADV180002 | Guidance to mitigate speculative execution side-channel vulnerabilities.

Is empty if Edge was not found.

CVE-2017-5753 mitigated in IE (aka Spectre Variant 1)

Is true if one of the following Windows Updates is installed: 'KB4056890', 'KB4056895', 'KB4056894', 'KB4056568', 'KB4056893', 'KB4056891', 'KB4056892'

The list of updates was obtained from ADV180002 | Guidance to mitigate speculative execution side-channel vulnerabilities.

Also see Mitigating speculative execution side-channel attacks in Microsoft Edge and Internet Explorer for details.

Is empty if IE was not found.

CVE-2017-5753 mitigated in Chrome (aka Spectre Variant 1)

Is true if C:\Program Files (x86)\Google\Chrome\Application\chrome.exe is version >=64, or 63 and Site Isolation is enabled by policy.

See Google’s Mitigations Against CPU Speculative Execution Attack Methods, Actions Required to Mitigate Speculative Side-Channel Attack Techniques for details.

Read more about Site Isolation and enable if desired as follows:

HKEY_LOCAL_MACHINE\Software\Policies\Google\Chrome\SitePerProcess is 1.

See also Policy List/SitePerProcess.

Is empty if Chrome was not found.

CVE-2017-5753 mitigated in Firefox (aka Spectre Variant 1)

Is true if C:\Program Files\Mozilla Firefox\firefox.exe or C:\Program Files (x86)\Mozilla Firefox\firefox.exe is version >=54.0.7

See Mitigations landing for new class of timing attack for details.

Is empty if Firefox was not found.

Roles

isHyperV

Is true if vmms (Hyper-V Management) Service is running.

Hypervisors are at increased risk.

isTerminalServer

Is true if TerminalServerMode is 1.

Terminal Servers (Remote Desktop Servers) are at increased risk.

isDocker

Is true if PATH system variable contains docker (which is the default).

Container hoster are at increased risk.

SpeculationControlSettings

BTI*

BTI is Branch Target Injection as described in CVE-2017-5715 alias Spectre (Variant 2).

This vulnerability requires always a microcode update for the CPU, which will be offered by the hardware OEM.

These properties might give you further insights, why CVE-2017-5715 mitigated is false.

KVA*

KVA or Kernel VA (also known as KPTI (Kernel page-table isolation) or KAISER) removes the mapping of kernel memory in user space process and thus mitigates the practical explotation of CVE-2017-5754 alias Meltdown.

KVAShadowPcidEnabled, too, needs the microcode CPU update that comes with a BIOS/firmware update by your vendor.

These properties might give you further insights, why CVE-2017-5754 mitigated is false.

Registry Keys

OSMitigationRegKeySet

As per Windows Server guidance to protect against speculative execution side-channel vulnerabilities:

Customers need to enable mitigations to help protect against speculative execution side-channel vulnerabilities.

Enabling these mitigations may affect performance. The actual performance impact will depend on multiple factors, such as the specific chipset in your physical host and the workloads that are running. Microsoft recommends that customers assess the performance impact for their environment and make necessary adjustments.

OSMitigationRegKeySet is true if the values for the registry key Memory Management are set as required, i.e. FeatureSettingsOverride is 0 and FeatureSettingsOverrideMask is 3. OSMitigationRegKeySet is empty if the computer is a client.

To create the required values, you can use the following PowerShell commands:

New-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management' -PropertyType 'DWORD' -Value '0'  -Name 'FeatureSettingsOverride'
New-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management' -PropertyType 'DWORD' -Value '3'  -Name 'FeatureSettingsOverrideMask'

Note: This is not required for Clients.

AVCompatibility

As per Important information regarding the Windows security updates released on January 3, 2018 and anti-virus software, the security updates are only installed, if the registry value cadca5fe-87d3-4b96-b7fb-a231484277cc is present in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat.

The value is either set by the the installed Anti-Virus, or must be set manually if no Anti-Virus is installed.

To add the value manually, you can use the following line of PowerShell:

New-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat' -Name 'cadca5fe-87d3-4b96-b7fb-a231484277cc' -PropertyType DWord -Value '0x00000000'

Note: Only use this command, if you don't have any Anti-Virus installed, or verified that it's compatible!

MinVmVersionForCpuBasedMitigations

If Hyper-V is installed, an additional Registry value has to be taken care of. MinVmVersionForCpuBasedMitigations is the value of the minimum supported VM version for CVE-2017-5715 fix of VM guests. If Hyper-V is not active, it's empty.

From Protecting guest virtual machines from CVE-2017-5715 (branch target injection)

By default, virtual machines with a VM version below 8.0 will not have access to updated firmware capabilities required to mitigate CVE-2017-5715. Because VM version 8.0 is only available starting with Windows Server 2016, users of Windows Server 2012 R2 or earlier must modify a specific registry value on all machines in their cluster.

To give every VM version access to the updated firmware capabilities, you can use the following PowerShell code:

if ((Get-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Virtualization' -ErrorAction SilentlyContinue).MinVmVersionForCpuBasedMitigations) {
    Set-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Virtualization' -Name MinVmVersionForCpuBasedMitigations -Value '1.0'
}
else {
    New-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Virtualization' -Name MinVmVersionForCpuBasedMitigations -PropertyType String -Value '1.0'
}

*Note: A cold reboot of each VM is required. Rebooting the OS from inside the Guest is not sufficient to make the setting effective. You have to Turn the machine off and on again.

This can be considered as the Hyper-V Guest equivalent to "microcode CPU update from hardware OEM".

History

0.4.2

• * issue with 'CVE-2017-5753 mitigated in IE' and PSv2 fixed

0.4.1

• * fixing "Firefox.exe located in Program Files (x86) #1"

0.4

• + MinVmVersionForCpuBasedMitigations added

0.3.1

• * OSMitigationRegKeySet fix

0.3

• + CVE properties added
• + CVE-2017-5753 for Edge, IE, Chrome, and Firefox
• + isDocker check
• + Get-SpeculationControlSettings updated to 1.0.2

0.2

• + PowerShellv2 support