Speculative Execution Check

Apply recommended settings to the registry using PowerShell

You will need to review the requirements of your system, however, the settings shown below are those we have used widely to eliminate this issue. 

Microsoft Article reference this issue

Registry Commands

reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /f /v FeatureSettingsOverrideMask /t Reg_DWORD /d 3
reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /f /v FeatureSettingsOverride /t Reg_DWORD /d 8

PowerShell Script

#Microsoft Windows Speculative Execution Configuration Check - Recommended settings 1
# - SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\
# FeatureSettingsOverrideMask: 0x00000003 (3)
# - SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\
# FeatureSettingsOverride: 0x00000008 (8)
# CVEs Covered: CVE-2017-5715, CVE-2017-5754, CVE-2018-3639
# Note: Remaining protections enabled by default on clients. Required for CVE-2018-3639.
Write-Host "Setting FeatureSettingsOverrideMask = 3"
$val = Get-ItemProperty "HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" -Name "FeatureSettingsOverrideMask"
if($val.AutoCheckSelect -ne 3)
{
set-itemproperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" -Name "FeatureSettingsOverrideMask" -value 3
Write-Host "FeatureSettingsOverrideMask now set to 3"
}
else
{
Write-Host "FeatureSettingsOverrideMask = No change required"
}
Write-Host "Setting FeatureSettingsOverride = 8"
$val = Get-ItemProperty "HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" -Name "FeatureSettingsOverride"
if($val.AutoCheckSelect -ne 8)
{
set-itemproperty -Path "HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" -Name "FeatureSettingsOverride" -value 8
Write-Host "FeatureSettingsOverride now set to 8"
}
else
{
Write-Host "FeatureSettingsOverride = No change required"
}

Please review the potential requirements of this issue as we have seen a number of different recommendations depending on the machine being assessed.