Windows 10: To mitigate meltdown insecurity threat CVE-2017-5754 Rogue Data Access using C/C++ high...

I have a query on spectre and meltdown insecurity threats to modern CPUs. How can software developers
can mitigate these in their c/c++ code. I have a query

Can we mitigate meltdown variant CVE-2017-5754 called as Rogue Data Access
in c/c++ logic? or in MSVC compiler? or in Visual Studio compiler?
regards
sachindeo

:)

 

spectre and meltdown vulnerabilities fix causing bsod for windows 10

Hello all ,

Post applying the spectre and meltdown vulnerabilities fix for couple of system of my mixed environment,i see few of win10 systems are crashing post applying following setting and restarting due to BSOD . where as my environment having Intel and AMD family
Processors and same solution worked perfectly for Win-7 and Win 8 with out any Noise .where as for W10 out 30 test machines 15 got crashed.

Config-applied :

Manage Speculative Store Bypass and mitigations around Spectre Variant 2 and Meltdown

Applies to: Windows 10, version 1803, Windows 10, version 1709, Windows 10, version
1703, Windows 10, version 1607, Windows 10, Windows 8.1, and Windows 7 SP1.

Enable mitigations around Speculative Store Bypass (CVE-2018-3639) together with mitigations around Spectre Variant 2 (CVE-2017-5715 "Branch Target Injection") and Meltdown (CVE-2017-5754) through the following registry settings
(because they are not enabled by default).

• 
  [table][tr][td]reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride /t REG_DWORD /d 8 /freg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverrideMask /t REG_DWORD /d 3 /f[/td][/tr][/table]
  
  Note These registry changes require administrative rights and a restart.
  

• Disable mitigations around Speculative Store Bypass (CVE-2018-3639) through the following registry settings.
  
  
  [table][tr][td]reg delete "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride /freg delete "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverrideMask /f[/td][/tr][/table]
  
  Note These registry changes require administrative rights and a restart.
  

any suggestion and solutions ...

Thanks ,

Naresh.

 

meltdown patch related question.

I was able to go through some hoops and was able to get the latest microcode for my Intel kaby lake processor loaded using this Vmware windows driver tool. However there doesn't seem to be a way to enable the windows patch on the fly unfortunately. Is there
anyway to get windows to enable the meltdown patch after boot up? I do hear the patch is being pulled because of the AMD issue so who knows now totally. I was mainly trying to do this so on old machines with no hope of a BIOS update anytime soon could be
patched.

Now I get this on the patch test.

PS C:\script\SpeculationControl> Get-SpeculationControlSettings

Speculation control settings for CVE-2017-5715 [branch target injection]

Hardware support for branch target injection mitigation is present: True

Windows OS support for branch target injection mitigation is present: True

Windows OS support for branch target injection mitigation is enabled: False

Windows OS support for branch target injection mitigation is disabled by system policy: False

Windows OS support for branch target injection mitigation is disabled by absence of hardware support: False

Speculation control settings for CVE-2017-5754 [rogue data cache load]

Hardware requires kernel VA shadowing: True

Windows OS support for kernel VA shadow is present: True

Windows OS support for kernel VA shadow is enabled: True

Windows OS support for PCID performance optimization is enabled: True [not required for security]

Suggested actions

* Follow the guidance for enabling Windows Client support for speculation control mitigations described in https://support.microsoft.com/help/4073119

BTIHardwarePresent : True

BTIWindowsSupportPresent : True

BTIWindowsSupportEnabled : False

BTIDisabledBySystemPolicy : False

BTIDisabledByNoHardwareSupport : False

KVAShadowRequired : True

KVAShadowWindowsSupportPresent : True

KVAShadowWindowsSupportEnabled : True

KVAShadowPcidEnabled : True

Moved from Windows / Windows 10 / Security & privacy )

 

I thought that version 1709 build 16299.192 addressed the Meltdown flaw...

OK this is what I'm seeing and bear in mind Dell hasn't so far issued a new updated firmware for this laptop:

PS C:\WINDOWS\system32> Get-SpeculationControlSettings

Speculation control settings for CVE-2017-5715 [branch target injection]

For more information about the output below, please refer to https://support.microsoft.com/en-in/help/4074629

Hardware support for branch target injection mitigation is present: False

Windows OS support for branch target injection mitigation is present: True

Windows OS support for branch target injection mitigation is enabled: False

Windows OS support for branch target injection mitigation is disabled by system policy: False

Windows OS support for branch target injection mitigation is disabled by absence of hardware support: True

Speculation control settings for CVE-2017-5754 [rogue data cache load]

Hardware requires kernel VA shadowing: True

Windows OS support for kernel VA shadow is present: False

Windows OS support for kernel VA shadow is enabled: False

Suggested actions

* Install BIOS/firmware update provided by your device OEM that enables hardware support for the branch target injection mitigation.

* Install the latest available updates for Windows with support for speculation control mitigations.

* Follow the guidance for enabling Windows Client support for speculation control mitigations described in https://support.microsoft.com/help/4073119

BTIHardwarePresent : False

BTIWindowsSupportPresent : True

BTIWindowsSupportEnabled : False

BTIDisabledBySystemPolicy : False

BTIDisabledByNoHardwareSupport : True

KVAShadowRequired : True

KVAShadowWindowsSupportPresent : False

KVAShadowWindowsSupportEnabled : False

KVAShadowPcidEnabled : False